deck machinery and cargo operations .pptx

machinery on the ships for cargo operation and mooring

1. 2 J anua r y 2021 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G DECK machinery and cargo system

2. Deck machinery is also called ship deck machinery. it is a kind of mechanical machinery installed on the ship’s deck. Deck machinery is also a necessary mechanical equipment or device for ship docking, loading and unloading cargo, passengers’ getting on and off. Ship deck machinery mainly includes anchor windlass, winch, fair-lead, mooring bollard, lift boat davit, deck fittings, etc. INTRODUCTION

3. Deck machineries for cargo ships The various items of machinery and equipment found outside of the machinery space of modern cargo ship. These include deck machinery such as mooring equipment, anchor handling equipment, cargo handling equipment and hatch covers. Other items include lifeboats and life rafts, emergency equipment, watertight doors, stabilizers and bow thrusters. The operations of mooring, cargo handling and anchor handling all involve controlled pulls or lifts using chain cables, wire or hemp ropes. The drive force and control arrangements adopted will influence the operations. Several methods are currently in use, and these will be examined before considering the associated equipment. Three forms of power are currently in use: steam, hydraulic and electric, Each got its advantages and disadvantages for particular duties or locations.

4. The other auxiliary machineries includes Deck gear s , Small de c k machinery, Winches and hatch covers . Cargo pumping and ballast system on tankers

5. Mast a nd Derricks  Ma st is a ve rtic al s p a r p r imaril y meant to ca r r y sa ils b ut it is a ls o u s e d to ca r r y r a d a r, sa tellit e ae ri a ls, a n d n avigatio n a l ligh t s.  The s e a r e mad e eith e r of woo d o r s t e e l.  Der r ic k is a la r g e sp a r fix e d to ma st b y go o s e n ec k an d it is u se d lik e a c r a n e fo r ho isti n g h e a v y weig h ts.

6. Block , P ulleys and Fish pump  The s e a r e co mmon in all ty p es o f fis hi n g v e s se l a n d a r e u s e d fo r a va ri e ty of pu r p o s e s like lea di n g the r o p es to co n v e nient p o siti o n s for h a n dling the ne t.  A b lo ck is a woo d e n o r met a l case in whic h o n e o r mo r e sheaves a re fit t ed .  Fish p u mp s a r e mainl y u s e d o n p u rs e seiner s to tra n s fe r the ca tc h f r o m n e t t o th e d ec k.

7. Rol l er s an d Gantries  Powe r e d s t e r n r o ller s a r e u s e d in g ill n ett e rs to h a ul t h e gill n ets b y n et re el s .  I n Da n is h s ei n e r s, to win g rollers a r e u s e d t o h a ul t h e ro p e.  Ga n tr y is a f o u r - i n- o n e co nt r iva n c e u s e d in t r awle r s whi c h re pl ac e s g a llow s , m ast, d e r rick a n d stays.  It ass is ts in p osition in g o f wa r p le a d s , hi tc hi n g o f o t t e r b o a r d s a n d lifti n g h e a v y c a tc h es e tc.

8. Moo r i ng w i n dl as s . No r ma ll y e i t h e r an elect r i c o r Hyd ra ul i c m oto r d r i ve s 2 c a bl e l i f te r and 2 w arp e n d s. T h e re are many de s i g ns bu t du e t o s lo w sp ee d o f c a bl e l i f te r ( 3 - 5rpm) a s lo w sp ee d wo r m ge ar and a s i n gl e s te p sp u r ge ar betwee n c a bl e l i f te r and w arp e nd i s u s ed A n c h o r C aps t ans . V e r t i c al c aps t ans u se a ve r t i c al sha f t , w i t h t he m oto r and ge ar box s i tu a te d belo w t he w i n c h u n i t (u s u a ll y belo w deck s. W i t h l ar ge r c a ble s t he c aps t an b arr el s i s m ou n te d s e para tel y o n an ot h e r sha f t W i n c h w i n dl ass e s . T h i s arran ge m e nt u s e s a m oo r i ng w i n c h t o d r i v e t he w i n dl ass. B ot h p o rt and s t ar bo a r d u n i t s are i n te r co nn ecte d t o f a c i l i t a t e s t an db y and a dd i t i o nal p owe r sh oul d t he s i tu a t i o n ar i se C o n ve nt io na l e q ui p men t 866 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 J anua r y 2021

9. S t o r a g e pa r t o f the moori ng d r um P u lli ng se ct io n o f the d r um ( w or k i ng pa r t) B r a k e band Ge ar b o x E le ct r o- h y d r au li c mo t o r W a r p i ng h e ad C ha i n i n the gy p s y w h ee l D o g c l u t ch Anch o r H a w s e p i pe Spu rli ng p i pe C ha i n lo c k e r C ha i n s t o pp e r wi th se cu ri ty d e v i ce G u i de r olle r B oll a r d G u i de r olle r D e ck H at ch t o ch ai n lo c k e r M oo r in g e q ui p men t 867 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 J anua r y 2021

10. W inches  W i nches are used c o m m on l y i n t raw l ers , purse se i ners and D an i sh se i ners to hau l the net and the ca t ch on to the board.  W i nches are used for d i fferen t f i sh i ng me t hods l i ke s i ng l e drum (spl i t t ype) , t w o -drum on on e shaf t or mo r e drum s on para ll e l shaf t s (doubl e rigg i ng and p urse se i n i ng). T h e r e a re di f f e r e n t kind s of winch e s . T h ey a r e dis t i n ct f r o m e a ch ot h er de p e n ding on t h e i r u s e. T h e r e a r e 7 typ e s of wi n ch e s cu r r e n t l y av a i l a b l e t h e r e. F o r e x a m p l e – Lev e r winch S n u b bi n g Winch Wa k e s kat e winch G l ide r Winch Air Wi n ch Ca p st a n wi n ch Moo r i n g winch  They are p l aced i n the fore and a ft d i rec t i on depend i ng on the requ i re m ent.  Winches can be driven e i t he r me c hanica ll y f ro m th e main engine or e l ec t rica ll y or hyd ra u li cal l y or d i re ct driv e by separa t e eng i ne.

11. L e v e r Winc h: L e v er w i n ch es a r e p a r ticula r kinds o f w i n ch es th a t do n o t u s e s p oo l s . I n s t ead o f a s p oo l , th e y h a v e S e l f - g r i p pi n g j a w s . The r e f o r e, th e y u s e S e l f - g r i p pi n g j a w s f o r m o v i n g c abl e o r r o p e th r o ugh th e w i n ch. O n e c an m o v e s e v e r al t o ns o f w eig h t o nl y by m o v i n g a h andl e b ack and f o r th b y u s i n g a l e v er w i n ch. Snu b bing Winc h: Sn ubbi n g w i n ch is a w i n ch o f a v erti c al sp o o l. It has r a t ch e t mecha n is m li k e a c o n v e n ti o nal w i n ch. Bu t i t ha s no c r an k handl e o r anot h er ty p e o f dr i v e l i k e a s t and a r d w i n ch . T h e l i n e c an b e r e e l ed and tig h t ened by pul l i n g t ail l i ne. S nubbi n g Winch al s o all o w s a c o n t r o l l ed r el ease o f p r essu r e . T o c o n t r o l s t r ess, i t u se s an o p e r a t o r a r o und th e r a t ch et ed sp o o l. A ls o , i t c o n t r o ls p r essu r e u s in g th e fr i ct i o n o f th e l i ne. W a k e - s k a t e Winc h: W a k es k a t e w i n ch us i n g is g r ow in g w i d el y amo n g th e w a t e r s p o r ts e n thu s ia s ts. It is a f a v o r i t e pa s ti me f o r them. It f o r ms o f a s p oo l , engin e, f r ame, handl es, r o p e and ot h er ty p es o f s im p l e t r an sm i ss i o n s. G l ider Winc h: F o r launchi n g a gli d er o r p lan e, w e u s e a p a r ticula r ty p e o f w i n ch. It is the glid er w i n ch. Usual l y , w e f i t th em t o a he a v y v ehicl e o r a t r ail e r . T his m e th o d is a ch eaper al t ern a ti v e t o ae r o t ow ing . E u r o pean gli d i n g cl u b s w i d el y u s e this m e th o d. I n a gl i d er w i n ch , th e engin e is us u all y o f p e t r o l , d i esel o r L P G. Y o u w i l l al s o f i n d w inches h a v ing el e ctric o r h y d r aulic eng i nes . Th i s w inch c an p ull in a 100 t o 160 - m e t er c able a tt ached t o the gl i de r . A f t er a st e e p and sho r t cl i mb , y o u c an r el ease th e c abl e a t th e heig h t o f 4 t o 70 m et e r s. A ir Winch: A i r w i n ch is also kno w n as ai r tug g er o r ai r h o i s t. T his w i n ch is th e ai r - p o w e r ed v e r s i o n o f a w i n ch. It c an l i f t th e m at eri als. Y o u c an al s o util i z e th em f o r th e s u s pensi o n o f m at eri als . T h e y a r e mo r e du r abl e, v e r s a til e and s a f er than hy d r aul i c, di esel and el ectr i c w i n ches. Th a t 's wh y v a r i o u s c om p ani es of t en p r e f er t o u s e ai r wi n ches. Ca ps t an W inc h : Ca p s t an w i n ch is a v erti c a l - a x l e w i n ch. It is a r o t a tin g d e v i ce ma d e f o r us i n g o n sa i l i n g s hi ps . Sa ilo r s u s e this w i n ch in sa i l i n g s hi p s t o appl y f o r ce t o th e c abl es and r o pes. T h e pr i nci p al o f the c a p s t an w i n ch is s im i la r t o th e w i n dla ss. M o o ring Winc h: Moor i n g w i n ch is a mechani c al d e v i ce. It is use d t o sec u r e a s hip t o th e b erth . It is a d e v i ce w i t h som e b a r r els th a t pul l s t h e c abl es o r w i r es. T o b erth, th e s hip as h o r e moor i n g w i n ch p l ay s a s i g ni f i c a n t r o le.

12. W indlass  W i nd l a s s i s s pe c i a l t y p e of w i n c h us e d for han d li ng an c ho r c h a i n.  Thi s i s a l s o be d r i v e n w i th e l e c tr i c o r hyd r au l i c.

13. Ne t Hauler s an d Ne t Drums  N et ha u lers are des i gn e d to su i t the f i sh i ng met ho d a n d po p u l ar most l y on t raw l ers , g i l l nette r s an d purse se i ners.  Th e y may be f i t t ed on the ra i l s on deck or hun g f r om a bo o m.  N et ha u lers can be dr i ven mechan i c a l l y, e l ect r i c a l ly or hydrau l i ca l l y.  N et Drums are used in g i l l nett i ng, t ra w ling an d se i n i ng.  Th e y d i f f er f r om net ha u lers in that t he ent i re net i s w o un d on t he drum.  Most net drums are f i t t ed at the stern.  Th e se a l so prevent the fou l ing of the ge a r dur ing the op e rat i on.

14. Lin e Haulers  L i ne ha u lers are used i n he a v ing the li nes.  L i ne ha u lers are used i n h a u l i n g the tro l l i n g li n e s, ha n d l i n e s an d ji g gi n g li nes.  O t her mach i ner ies li ke w ater separators, co i l er, bra il e r , p o w e r b l ock s , tr i p l ex, ji ggin g mach ines etc.

15. a piece of marine device to hold a boat in place. The winch contains a drum divided into working part and storage part. This mooring winch has functions such as shifting, holding and positioning for loading and unloading. They can operate in various ways and are fixed in place on the deck of a ship in key positions. Sailors should carefully position and secure the ship when it comes into port. Some mooring winches are electric ,hydraulic or controlled with gas generators. The lines can be quite dangerous for unwary sailors and passengers, who may not be aware of the risk if the mooring winch equipment is being operated remotely. MOORING WINCH

16. Windlass is a machine used on ships, which can heave up equipment such as a ship's anchor or a fishing trawl. It is designed not only to meet class requirements but also operational needs, which are often seen in off-shore tugs and vessels. The windlass duty ratings are greatly increased to match greater anchoring depths. Windlass controls at remote wheelhouse for out-of-sight operation is optional. Windlass

17. An anchor windlass is a machine that restrains and manipulates the anchor chain or rope on a boat, allowing the anchor to be raised and lowered. A brake is provided for control and a windlass is usually powered by an electric or hydraulic motor. This windlass is suitable for anchor chain diameters ranging from 19 mm to 120 mm. Winches can be hydraulic, electric or diesel driven and are available in vertical and horizontal positions. used to haul up the anchor , to kedge off, deploy a second anchor, raise a sail, serve as an emergency tow point, or provide assistance in high wind and current berthing situations. The anchor raising system carries heavy loads and can be dangerous. The operator should simply push the button or crank the handle to deploy or raise the ground tackle. Anchor Windlass

18. ANCHOR WINDLASS

19. Located separately but close to the mooring winches or as an integral part of them, the windlass is the device used for lowering and raising the anchor it does this in tandem with the bow or chain stopper which prevents chain slippage when anchored and when raising the anchor. The anchor chain passes from the anchor and through the hawse pipe, over the windlass and down into the chain locker where the end is secured. The windlass is driven by a motor, either electric or hydraulic, and features a brake and clutch for use in different operations. Anchoring is usually done in one of two ways; letting go or walking back. Before anchoring the anchor chain must be released from its lashings on the bow stopper .

20. For harbor tugs and escort duty tugs, we design a small diameter windlass to adapt to a high power winch drum. To meet operational requirements, with built-in automatic rope render-recovery feature, the winch drum is fitted with rope tension and length readout. We recommend to our customers that all towing escort winch should be equipped with an emergency release system. Windlass/ Towing Winch

21. TOWING WINCH

22. As an option for simple mooring applications, clients can choose remote wheelhouse for out-of-sight operation with length readout and winch controls. Tension control system can also be built into the system, allowing the moored vessel to compensate for draft changes during loading or unloading operations or tidal changes.   Windlass/ Mooring Winch

23. MOORING WINCH

24. MOORING WINCH

25. A winch is a marine deck equipment device for handling wires or ropes and works by spooling the wire or rope on a drum with a horizontal axis. The winch can be powered by electric or hydraulic motors; steam winches were once common but are now obsolete. Winches on ships are fixed and used for specific purposes. As previously mentioned cargo derricks are now much less common and so the winches needed to provide power for these have also been more or less abandoned. The most common use of a winch is for mooring meaning the winches are mostly located on the fore and after decks at both sides of the ship. Tugs and offshore vessels such as AHTS, seismic survey and OSVs will also be equipped with work winches designed for the very heavy duty work these ships are used for.

26. A nch o r D r o p ! 868 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 J anua r y 2021

27. E f f i c i e nt wo r k i ng o f t he an c h o r w i n dl ass i s e ss e n t i al t o t he sa f et y o f t he sh i p. I t ’ s de s i g n and p e r f o rman c e i s s ub j ecte d t o s t r i c t cl ass i f i c a t i o n s oc i et y r ule s. B as i ca ll y th ey re q u i re th at Ca b l e l ift er b ra k e s h a l l b e ca p a b l e of co nt r o ll ing th e ca b l e a n d a n c h o r wh en di sco nn ec t ed f ro m th e gear in g at l e ttin g go. T h e A v . Sp eed of ca b l e s h a l l b e 5 - 7 m / s. T h e h eav in g ca p ac it y s h a l l b e 4 - 6 ti mes th e w e i g h t of o n e a n c h o r at s p ee d s b e tw een 9 a n d 15 m / m in u t e . T h e l iftin g w t s h a l l b e b e tw een 20 - 70 t o nn es. T h e b ra kin g e ff ort o bt a in ed at th e l ift er s h a l l at l east 40 % of th e b rea k in g s t re n g t h of th e ca b l e. A nch o r H an d li n g 869 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 J anua r y 2021

28. T h e wind l ass must b e ca p a b l e of pu ll in g th e a n c h or f r om a d e pt h of 25 % of th e t o t al ca b l e carrie d , i. e. 50 % of th e l e n g t h of c h a i n on o ne s id e. I t s h ou l d b e ca p a b l e of l iftin g the a n c h o r f ro m 82 . 5 m t o 27 . 5 m at 9 m / m in. N ormal a n c h o r h a nd l in g e q u ip me n t in cor p ora t es w arp e nd s f o r moori n g pu r p oses wit h l i g h t l in e s p eed of up t o 1 m / sec. A nch o r H an d li n g 870 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 J anua r y 2021

29. T h e anc h or in g eq u i p me n t f itte d to t h e m a j or ity o f v e ss e l s c o n sists o f tw o m a tc hed u n its , o ff e r in g a de g r e e o f r ed u n d an c y . T he s e u n its c o n sists o f an anc h o r , c h ain ( o r f o r s m a ll e r v e ss e l s w i r e ) , a g y p s u m o r c h ain lif t e r w hee l , b r ak e , lif t m o t o r and v a r i ou s c h ain st o ppe r a rr an g eme n ts . W he n n o t in h e u s e t h e c h ain is st o w e d in a c h ain l o ck e r . S y stems f itt e d wit h wi r e a r e st o wed o n a d ru m i n t h e s a m e w ay a s wi n c he s. T he win d l a ss m u s t b e c a p a b l e o f p u ll in g t he an c h o r fr o m a d e p t h o f 25% o f t he tot a l c a b l e c a rr ie d , i . e. 50% o f t he l en g t h o f c hain o n o ne s i d e It s h o u l d b e c a p a b l e o f l i ft in g t he an c h o r fr o m 82 . 5m to 27 . 5m at 9 m / m in. A nch o r in g e q ui p men t 871 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 J anua r y 2021

30. Chain stopper

31. Chain stopper , cable  stopper . A fitting used to secure the anchor  chain  when riding at anchor, thereby relieving the strain on the windlass, and also for securing the anchor in the housed position in thehawsepipe. The  anchor chain stopper  is a device for holding the anchor chain to the windlass and the hawse hole. The anchor chain stopper is used for setting the anchor and discharge to the windlass.

32. Tugger winch

33. Electric tugger winches are driven by a single- or two-speed efficient electric motor or a state-of-the-art variable frequency drive. Line pulls range from five to 30 tonnes . A local control panel is situated adjacent to the winch. A wired-controller or remote-control from the wheelhouse are also available as options. All winches are also available with low-pressure and high-pressure hydraulic drives.

34. anchor fairlead

35. A  fairlead  is a device to guide a line, rope or cable around an object, out of the way or to stop it from moving laterally. Typically a fairlead will be a ring or hook. The fairlead may be a separate piece of hardware, or it could be a hole in the structure. A fairlead can also be used to stop a straight run of line from vibrating or rubbing on another surface. An additional use on  boats  is to keep a loose end of line from sliding around the deck. If the line is meant to be moved while in the fairlead, the angle in the line created by the fairlead must be shallow to minimize friction. For larger angles a  block  or pulley is used as a fairlead to reduce friction. Where the line is removed from a hook fairlead before using, the angle is not an issue.

36. M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 S J a a t n u u r a d r a y y 2 , J 2 a 1 nu a r y 2, 2021 E l e c tric d rives S h ou l d b e t o ta ll y e n cl o s e d DC d r i v e s a r e sti l l u s e d be ca u s e t he y g o t g oo d t or q u e r an g e ov e r t h e f u l l s pee d t h ou g h t hey n ee d r e g u l a r a tt e n ti o n. C o n t ro l o f c o n t a ct o r o pe r a t e d a r m a t ur e r e sis tance is f u ll y r ep l ac e d w ith W a r d L e o na r d s y s t e m f o r g oo d r e g u l a ti o n ; e s pe c ia ll y a t l o we r i n g l o a d s ( T h e p r e s e n t d ay W a r d L e o na r d g e n e r a t o r i s d r i v e n b y an A C m o t or ) D C m o t or s m ay a l s o b e c o n t ro ll e d b y t h y r ist or s w h ich c o n v e r ts A C to v a r ia b l e DC v o l t a g e . AC In d u cti o n m o t or s c an b e w ou nd ro t o r o r ca g e typ e . S pee d c o n t ro l be in g p o l e c h an g in g o r ro t o r r e sis tance c h an g e typ e . A n o t he r f or m o f A C m o t o r c o n t ro l be in g V FD d r i v e s w h ich c o n t ro l s t h e a pp li e d f r eq u e ncy and vo lt a g e . 872 D r ives

37. D r ives Hyd r a u l ic S yst e m s p ro v i d e a g oo d me an s o f d ist r i b u ti o n o f p o wer o b ta i n e d f ro m p u m p d r i v e n b y a c o n s tan t d i r e cti o n/ s pe e d A C m o t o r . T h is o i l c an b e m a d e to d r i v e t h ro ’ h y d r a u lic m o t or s to p o w e r t h e a ct u a ting de v ices . B o th c o n s tan t de liv e r y and v a r ia b le de l i v e r y t y p e p u mps and m o t or s a r e c o mm o n l y u s e T h e f i x e d ou t p u t p u mps c an b e o f t he W oo d wa r d h y d r a u l ic e n g i ne g o v e r n o r t y p e w h ich m aintain r e s e rv e o il a t p r e ss ur e to cat e r to dem and 873 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 J anua r y 2021

38. D r ives Hyd r a u l ic S yst e m s V a r i a b l e d is p l a c eme n t p u mps c an b e o f a x ial o r r a d ial p ist o n typ e s w he r e o pe r a ti o nal v a l v e s can b e a vo i d ed . I t is v e r y e ss e n tia l f o r a l l h y d r a u li c s y s t em s b e p rov i d e d w ith int e r l o ckin g a rr an g eme n ts f o r p u m p and m o t or s so t h a t c o n t ro l l e v e r s r em ain a u t o m a tica ll y in n e u t r al to a vo id ina d v e r t e n t s ta r t u p s . 874 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 J anua r y 2021

39. D r ives Hyd r a u l ic S yst e m s Ov e r l o ad p ro t e cti o n t h ro ’ r e l i e f v a l v e s to s a f e g u a r d s y st e m a t 30 - 40% o v e r p r e ss ur e A t m o s phe r ic c o nta m ina ti o n is o l a ti o n, o il c o mp a ti b ilit y , s y s t e m clean li n e ss , r e g u l a r rou tin e m aint e nance e tc. can s e e t h ro ’ l o n g pe r i o d s o f t rou b l e f r e e o pe r a ti o n 875 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 J anua r y 2021

40. Ca r g o winch n u mbe r s and ca p a city a r e de ci d e d in a d v an c e keepin g i n mi nd t h e n o o f h a tc he s and t he si z e to w or k. T h e s pee d v a r i e s f ro m . 45 m / s a t f u l l l o ad to 1 . 75 m / s a t lig h t l o ad w ith 40 kw a t f u l l l o ad o f 7 T and 20 kw f o r 3 T A d v anta g e o f t h e de rr ick s y s t e m is t h a t o n l y 2 winc he s a r e r eqd . and h a s a f a s t e r cycle tim e . B u t s a f e w or kin g l o ad is l e ss and tak e s q u ite s o m e tim e to r ig u p t h e s y st e m p r i o r to c a r g o w or k. S l e win g de rr ick s y s t e m wa s an e x c ep ti o n to t h e a b ov e and whic h c ou l d b e r i gg e d u p and c h an g e i n s e t u p wa s f a st e r . D ec k C r anes 876 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 J anua r y 2021

41. Marine hydraulic crane A marine hydraulic crane is a type of crane that is specifically designed to be used in marine environments, such as on ships, offshore platforms, and docks. It is typically powered by hydraulic systems that use pressurized fluids to generate mechanical force. The main advantage of hydraulic cranes is that they are able to lift heavy loads with ease and precision. They are also able to operate in harsh marine environments, including in high winds and rough seas, due to their sturdy construction and design. Marine hydraulic cranes come in a variety of sizes and types, with lifting capacities ranging from a few hundred kilograms to several tonnes . They are commonly used for a range of tasks on board ships and offshore platforms, including cargo handling, lifting and lowering equipment, and launching and retrieving boats and other vessels. In addition to their lifting capabilities, hydraulic cranes can also be equipped with various attachments and tools, such as hooks, grabs, and buckets, which can be used for specific tasks. Overall, marine hydraulic cranes are an essential tool for many marine operations and are designed to withstand the rigors of the sea while providing reliable and efficient performance.

42. A deck crane is a kind of machine, usually equipped with a hoist, wire ropes (chains) and sheaves. It can be used to lift and lower materials and also to move them horizontally. This ship crane is mainly used for lifting heavy things and transporting them to other places. The ship crane is widely applied in transport industry to load and unload freight, in construction industry to move materials and in manufacturing industry to assemble heavy equipment. Deck cranes cover the range of wire luffing cranes, cylinder luffing cranes, grab cranes, gantries and heavy lift cranes. DECK CRANES

43. 1. lifting capacity. 2. easy and convenient to operate. 3. impact resistance and good braking performance. 4. safe and reliable. It should own high loading and unloading efficiency of cargoes. 5. A good adaptability to cargoes. Necessary features

44. The structure of telescopic boom crane is compact, which makes it adaptable for many mobile applications. When it is not used, we can set the suspension arm to the minimum physical dimension. These telescopic boom cranes are usually used for short-term construction projects, rescue jobs, lifting boats in and out of the water, etc. These boom cranes can be hydraulically extended and retracted without a knuckle function. These cranes are always used with a hoisting winch installation. Telescopic Boom Crane

45. type of full rotational marine crane. Good performance, simple operation, reliable rotation, and flexible compact structure make it own high operation efficiency. This design offers a compact size for storage and control. Their arms are much lighter than boom truck cranes, and they are designed to allow for more payloads. This deck crane comes with different types of control systems, such as stand up, control from the ground, seat control and radio remote control. This deck crane may swing through an arc to give additional lateral movement.   Knuckle Boom Crane

46. KNUCKLE BOOM CRANE

47. Straight boom crane is designed for loading and unloading ship-borne containers at a port. It is capable of lifting and loading dangerous cargoes. It can be used as hose crane when working on oil products in chemical docks and also be used as hydraulic straight boom marine crane when installed on ships. Straight boom crane is often applied to where there are no many loading and unloading operations. This crane owns a hoist fixed on a trolley that runs horizontally along tracks and usually fitted on a single beam or two beams. The crane frame is supported by a gantry system with equalized beams and wheels. The hydraulic straight boom marine crane come in various sizes and some can move very heavy loads used in shipyards or industrial installations. Straight Boom Crane

48. 1. The straight boom crane can run smoothly. 2. Rates of speed can be changed with 360°rotation. 3. Both electro hydraulic and manual control are provided. 4. This crane is of high safety and reliability. 5. Hydraulic straight boom marine crane can be operated conveniently. FEATURES

49. STRAIGHT BOOM CRANE

50. Hydraulic circuit No. Name 1 Oil motor for hoisting winch 2 Oil motor for luffing winch 3 Oil motor for slewing device 4 Counter balance valve 5 Control valve 6 Electric motor 7 Oil pump 8 Relief valve 9 Oil cooler 10 Thermo switch 11 Filter 12 Oil tank 13 Unloading valve

51. S in g l e - o pe nin g & M u lt i - o pe n i n g . Can b e o pe r a t e d by t h e s h i p ’ s c r ane o r e x t e r nal he l p . S e a li n g be tw ee n h atch c ov e r s and c o a m in g is g e n e r a ll y ac h i e v e d b y s li d in g ru bbe r p ackin g Lift - a w a y hatc h co vers 877 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 J anua r y 2021

52. The f o l d i ng p a i r i s op e r a t e d b y h y d r a u li c c yl ind e r s a cting di r e ct l y on the e n d h i n g e a r ms w h i ch a r e c onn e c t e d a t s t oo l s on the d e c k . W h e n the c yli nd e r s pus h the e n d p a n e l u p f r om the c l os e d pos i t i on, the c o v e r i s f o l d e d a nd the s e c ond p a n el , f i tt e d w i th w h eel s, r o l ls on the r ail s t o the s t o w a g e pos i t i on Hy dr au lic F o l d in g T y p es 878 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 J anua r y 2021

53. S i de -r o lli ng ha t c h c ov e r s st o w i n a t r an s v e r se d ir e c t i on w h il e en d -r o lli ng types st o w l ong i tud i na ll y . T he t r ad i t i onal s i de -r o lli ng c ov er c ons i s ts of t w o pane l s per ha t c h, ea c h panel r o lli ng s i d e w ays on a pa i r of t r an s v e r se r a m p s, thus p r ese n t i ng a mi n im um o b st a c l e w hen l oad i ng. I n so m e c ases both pane l s c an be st o w ed t og e ther on one s i de t o fu r ther enha n c e a cc ess w hen l oad i ng and un l oad i ng. T h i s a l t e r nat i v e r edu c es day li g h t open i ng b y app r o xim a t e l y 50 % . R o lli n g t y p e s f o r co m b inat io n / dr y b u lk ca r r ie r s 879 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 2 J anua r y 2021

54. 18 S ep tem b er 2020 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G C a rgo Syste m s

55. kenRT/May-2002/ver 1.0 Competence 1 - Control fire-fighting operations on ships 102 IGS System with Zones Return

56. kenRT/May-2002/ver 1.0 Competence 1 - Control fire-fighting operations on ships 103 a division into gas‑dangerous and gas‑free spaces strict segregation between cargo spaces and systems and machinery accommodation spaces and systems Tactics Requirements on Tankers (cont’d)…

57. INERT GAS SYSTEMS (IGS) Introduction In the late sixties and up till today the shipping world has been shocked by several severe tanker explosions. In most cases it is believed that a proper use of inert gas in the tanks might have saved the ships and many lives. Consequently, IMO established rules, specifications for the design, construction and use of inert gas systems. (SOLAS Ch.II-2 and Guidelines on Inert Gas Systems). During operation, oil will nearly always have hydrocarbon gases in some or all of the cargo tanks. In certain periods, especially 1

58. during cargo handling and tank washing, the hydrocarbon gases may be mixed with air to explosive concentrations unless preventive measures are taken. Hydrocarbon gas normally encountered in oil tankers cannot burn in an atmosphere containing less than 11% oxygen by volume. Accordingly, one way to provide protection against fire or explosion in the vapour space of cargo tanks is to keep the oxygen level below 11% by volume. This is usually achieved by using a fixed piping arrangement to blow inert gas into each cargo tank in order to reduce the air content, and hence the oxygen content, and render the tank non-flammable. 2

59. Application (Ref. SOLAS Ch.II-2) For oil tankers of 20,000 tonnes DWT and upwards, fire protection of cargo tanks shall be achieved by a fixed inert gas system in accordance with the requirements of the Fire Safety Systems Code. Oil tankers operating with a cargo tank cleaning procedure using crude oil washing shall be fitted with an inert gas system complying with the Fire Safety Systems Code and with fixed tank washing machines. Double hull spaces shall be fitted with suitable connections for the supply of inert gas. Tankers fitted with a fixed inert gas system shall be provided wih a closed ullaging system. 3

60. I nert gas systems Inert gas is an essential requirement for chemical tankers, being used to maintain the quality of some cargoes, reducing cargo or oxidation or the formation of moisture, preventing dangerous chemical reactions, safety blanketing low flash cargoes, blowing and clearing ships' cargo lines and for ensuring the safety during washing processes of non-gas-free tanks. Most vessels are equipped with a system of nitrogen storage tanks or bottles that are replenished when empty. This method is preferred because it uses pure nitrogen and so is acceptable for all the above duties. Cargo planners must ensure that topping up facilities are available at sufficient port of call on long voyages overseas

61. Some chemical tankers are fitted with inert gas generators (flue gases are not used because of the variation of impurities) which burn liquid fuel and air in such a manner that as much oxygen as possible is burned. After combustion the gas consists mainly of nitrogen, carbon dioxide and water vapour . When cooled some of the vapour condenses and this liquid is separated off. The remaining gas is fed into a further cooler where the temperature is lowered to about +3 o C. The gas is then dried by passing it through silica gel which dries it to a dewpoint of -18 o C I nert gas systems

62. Inert gas system A typical specification for an inert gas is given below:    Nitrogen, N 2                          84 % Carbon dioxide, CO 2             15 % Oxygen, O 2                           0.5 % max. Carbon monoxide, CO          30 ppm max. Hydrogen                             100 ppm max.   Sulphur dioxide                    50 ppm max. Dewpoint                              -18 o C  

63. INERT GAS SYSTEM Why use inert gas systems? A fire needs heat, fuel and oxygen to develop. Taking away one of these elements in the fire triangle will stop or prevent a fire. Thus, an oxygen content in a tank below 8% achieved by addition of inert gas is one of the options for preventing the fire. As a measure to achieve tanker safety, the 1978 Protocol to the International Convention for the Safety of Life at Sea (SOLAS) include the requirement for Inert Gas Systems on all new tankers over 20,000 dwt.

64. REQUIREMENTS OF INERT GAS SYSTEM ALARMS High Oxygen content in Inert Gas main line. Low Gas pressure in Inert Gas Main. Low Pressure in water supply to the deck water seal. High Temerature of Gas in Inert Gas Main Low Water Pressure to the scrubber. High gas Pressure in Inert Gas Main.   SHUT DOWNS High Temerature of Gas in Inert Gas Main Low Water Pressure to the scrubber. High gas Pressure in Inert Gas Main. Cargo Pump shut down due to Casing high temperature Bearing High Temperature Motor overload Emergency Shut down High revolution of pumps (high speed trip)

65. EQUIPMENT INERT GAS GENERATORS NITROGEN GENERATORS NITROGEN CYLINDERS FGS (NOT USED GENERALLY ON CHEMICAL TANKERS)

66. INERT GAS SYSTEMS (IGS) Introduction In the late sixties and up till today the shipping world has been shocked by several severe tanker explosions. In most cases it is believed that a proper use of inert gas in the tanks might have saved the ships and many lives. Consequently, IMO established rules, specifications for the design, construction and use of inert gas systems. (SOLAS Ch.II-2 and Guidelines on Inert Gas Systems). During operation, oil will nearly always have hydrocarbon gases in some or all of the cargo tanks. In certain periods, especially 1

67. during cargo handling and tank washing, the hydrocarbon gases may be mixed with air to explosive concentrations unless preventive measures are taken. Hydrocarbon gas normally encountered in oil tankers cannot burn in an atmosphere containing less than 11% oxygen by volume. Accordingly, one way to provide protection against fire or explosion in the vapour space of cargo tanks is to keep the oxygen level below 11% by volume. This is usually achieved by using a fixed piping arrangement to blow inert gas into each cargo tank in order to reduce the air content, and hence the oxygen content, and render the tank non-flammable. 2

68. Application (Ref. SOLAS Ch.II-2) For oil tankers of 20,000 tonnes DWT and upwards, fire protection of cargo tanks shall be achieved by a fixed inert gas system in accordance with the requirements of the Fire Safety Systems Code. Oil tankers operating with a cargo tank cleaning procedure using crude oil washing shall be fitted with an inert gas system complying with the Fire Safety Systems Code and with fixed tank washing machines. Double hull spaces shall be fitted with suitable connections for the supply of inert gas. Tankers fitted with a fixed inert gas system shall be provided wih a closed ullaging system. 3

69. Definitions: Inert Gas means a gas or a mixture of gases, such as flue gas, containing insufficient oxygen to support the combustion of hydrocarbons. Inert Condition means a condition in which the oxygen content throughout the atmosphere of a tank has been reduced to 8 per cent or less by volume by addition of inert gas. Inert Gas Plant means all equipment specially fitted to supply, cool, clean, pressurize, monitor and control delivery of inert gas to cargo tank systems. Inert Gas Distribution System means all piping, valves, and associated fittings to distribute inert gas from the inert gas plant to cargo tanks, to vent gases to atmosphere and to protect tanks against excessive pressure or vacuum. 4

70. Inert Gas System means an inert gas plant and inert gas distribution system together with means for preventing backflow of cargo gases to the machinery spaces, fixed and portable measuring instruments and control devices . Inerting means the introduction of inert gas into a tank with the object of attaining an inert condition as defined above . Topping-up means the introduction of inert gas into a tank which is already in an inert condition with the object of raising the tank pressure to prevent any ingress of air. Purging means the introduction of inert gas into a tank already in an inert condition with the object of : - further reducing the oxygen content; and/or - reducing the existing hydrocarbon gas content to a level below which combustion cannot be supported if air is subsequently introduced into the tank . 5

71. Effect of Inert Gas on Flammability A Flammability Composition Diagram is given in figure 1. The effect of inert gas on flammability has already been explained earlier. (Ref. Flammability and Explosiveness given in, Hazards associated with the handling and carriage of petroluem, slides 32 to 37). 6

72. 1 7

73. 8 Sources of Inert Gas The possible sources of inert gas on oil tankers are: - the uptake from the ship’s main or auxiliary boilers (boiler flue gas); or - an independent inert gas generator; or - a gas turbine plant when equipped with an after burner. Quality of Inert Gas Good combustion control in ship’s boilers is necessary to achieve an oxygen content of 5 per cent by volume. In order to obtain this quality, it may be necessary to use automatic combustion control.

74. 9 Methods of Gas Replacement There are three operations which involve replacement of gas in cargo tanks, namely; Inerting; purging; gas-freeing. In each of these replacement operations, one of two processes can predominate: - dilution, which is a mixing process; - displacement, which is a layering process.

75. INERTING PURGING OF HYDROCARBON CONTENT PRIOR TO AERATING INERT GAS INTRODUCED INTO CARGO TANK THROUGH LIQUID LINES DISPLACEMENT METHOD USED HYDROCARBON/INERT GAS MIXTURE VENTED THOUGH VAPOUR LINE TO TERMINAL FLARE OR VENTED THROUGH MAST RISER

76. 10 Dilution Method The dilution theory assumes that the incoming gas mixes with the original gases to form a homogeneous mixture throughout the tank. The result is that the concentration of the original gas decreases exponentially. In practice the actual rate of gas replacement depends upon the volume flow of the incoming gas, its entry velocity, and the dimensions of the tank. For complete gas replacement it is important that the entry velocity of the incoming gas is high enough for the jet to reach the bottom of the tank. It is therefore important to confirm the ability of every installation using this principle to achieve the required degree of gas replacement. See figures 2 and 3.

77. Changing Atmospheres - Dilution Mix of gases vented

78. Fig.2 shows an inlet and outlet configuration for the dilution process and illustrates the turbulent nature of the gas flow within the tank. Fig.3 shows typical curves of gas concentration against time for three different sampling positions. 11

79. Changing Atmospheres - Displacement Lighter Heavier N A I H itrogen ir nert Gas eavy cargo vapour Light cargo vapour

80. 12 Displacement Method Ideal replacement requires a stable horizontal interface between the lighter gas entering at the top of the tank and the heavier gas being displaced from the bottom of the tank through some suitable piping arrangement (e.g. Purge pipe). This method requires a relatively low entry velocity of gas and in practice more than one volume change is necessary. It is therefore important to confirm the ability of every installation using this principle to achieve the required degree of gas replacement throughout the tank. See figures 4 and 5.

81. 13 Displacement Method/Principle

82. 14 Figure 4 shows an inlet and outlet configuration for the displacement process, and indicates the interface between the incoming and outgoing gases. Figure 5 shows typical curves of gas concentration against time for three different sampling levels. General Policy of Cargo Tank Atmosphere Control Oil tankers fitted with an inert gas system should have their cargo tanks kept in a nonflammable condition at all times (see figure 1). It follows that: - tanks should be kept in an inert condition whenever they contain cargo residues or ballast. The oxygen content should be kept at 8% or less by volume with a positive gas pressure in all the cargo tanks;

83. 15 - the atmosphere within the tank should make the transition from an inert condition to a gas-free condition without passing through the flammable condition. In practice this means that before any tank is gas-freed, it would be purged with inert gas until the hydrocarbon content of the tank atmosphere is below the critical dilution line (see figure 1); - when an oil tanker is in a gas-free condition before arrival at a loading port, tanks should be inerted prior to loading. In order to maintain cargo tanks in a non-flammable condition, the system is required to:

84. 16 - inert empty cargo tanks; - be operated during cargo and ballast handling; - purge tanks prior to gas-freeing; - top up pressure in cargo tanks when necessary. The Inert Gas System The Inert Gas System consists of three distinct parts, which: - produce the inert gas; - cool and clean the gas; - distribute the gas. Good quality inert gas from the generating plant, contains:

85. - Nitrogen … approx. 80% by volume; - Carbon Dioxide.. approx. 14% by volume; - Oxygen … approx. 4% by volume; - Water vapour … approx. 2% by volume; and small quantities of undesirable by-products such as nitrous oxides, sulphur dioxide, carbon monoxide and soot particles. The composition of inert gas is given in figure 6. 17

86. Figure 6 : Composition of Inert Gas 18

87. Inert Flue Gas System A typical arrangement for an inert flue gas system is shown in figure 7. It consists of flue gas isolating valves located at the boiler uptake points through which pass hot, dirty gases to the scrubber and demister. Here the gas is cooled and cleaned before being piped to blowers which deliver the gas through the deck water seal, the non-return valve, and the deck isolating valve to the cargo tanks. A gas pressure regulating valve is fitted downstream of the blowers to regulate the flow of gases to the cargo tank. A liquid-filled pressure vacuum breaker is fitted to prevent 19

88. 20 Fig. 7 : Inert Flue Gas System

89. excessive pressure or vacuum from causing structural damage to cargo tanks. A vent is fitted between the deck isolating/non-return valve and the gas pressure regulating valve to vent any leakage when the plant is shut down. For delivering inert gas to the cargo tanks during cargo discharge, deballasting, tank cleaning and for topping up the pressure of gas in the tank during other phases of the voyage, an inert gas deck main runs forward from the deck isolating valve for the length of the cargo deck. From this inert gas main, inert gas branch lines lead to the top of each cargo tank. 21

90. Inert Gas Scrubber The purpose of the scrubber is to cool the flue gas and remove most of the sulphur dioxide and particulate soot. All three actions are achieved by direct contact between the flue gas and large quantities of sea water. A diagram of a Scrubber is given in figure 8 Before entering the bottom of the scrubbing tower, the gas is cooled by being passed either through a water spray, or bubbled through a water seal. In the scrubbing tower itself the gas moves upwards through downward flowing water. For maximum contact between gas and 22

91. Figure 8: Scrubber 23

92. Scrubber Tower Start S.W. Pump Demister Baffle Plates Flow Meter

93. Scrubber Tower S.W. Pump Running Demister Water Spray Baffle Plates Precooling Spray Water Seal Overflow Drain Start I.G. Flow Meter

94. Scrubber Tower Demister Water Spray Baffle Plates S.W. Pump Running Precooling Spray Water Seal Overflow Drain I.G. Blower started I.G. Outlet To Blower I.G. Inlet From Boiler Flow Meter

95. water, several layers made up of one or more of the following arrangements are fitted: - spray nozzles; - trays of ‘packed’ stones or plastic chippings; - perforated impingement plates; etc. At the top of or downstream of the scrubbing tower, water droplets are removed by one or more demisters which may be polypropylene mattresses or cyclone dryers. The scrubber should be capable of dealing with the quantity of inert gas required, and its construction should allow for hot corrosive gases. 24

96. The performance of the scrubber at full gas flow should be such as to remove at least 90 per cent of sulphur dioxide and to remove solids effectively. Drainage of the effluent should not be impaired when the ship is fully loaded. In product carriers more stringent requirements may be needed for product quality. Inert Gas Blowers Blowers are used to deliver the scrubbed flue gas to the cargo tanks (See figure 7). SOLAS requires that at least two blowers shall be provided which together shall be capable of delivering inert gas to the cargo tanks at a rate of at least 125 per cent of the maximum rate of discharge capacity of the ship expressed as a volume. 25

97. Each blower has an inlet valve and a discharge valve. Blowers may also have an air inlet and may therefore also be used to gas-free cargo tanks (See figure 7). Corrosion-resistant materials or coatings must be used in the construction of blowers and casings to protect them from the corrosive effect of the gas. Fan casings should be fitted with drains to prevent damage by an accumulation of water. Means should be provided such as fresh water washing to remove the build-up of deposits which could cause vibration during blower operation. Sufficient openings should be provided to permit inspection. 26

98. Failure of the blowers should be indicated by an alarm (SOLAS Ch.II-2). Means should be fitted for continuously indicating the temperature and pressure of the inert gas at the discharge side of the blowers (SOLAS Ch.II-2). Inert Gas Blowers should shut down automatically in the event of: - Low water pressure or low flow rate in the scrubber; - High water level in the scrubber; - High gas temperature. (SOLAS Ch.II-2) 27

99. The Blower pressure/volume characteristics should be matched to the maximum system requirements. The characteristics should be such that in the event of the discharge of any combination of cargo tanks at maximum discharge rate, a minimum pressure of 200 mm water gauge is maintained in any cargo tank after allowing for pressure losses due to: The scrubber tower and demister; The piping conveying the hot gas to the scrubbing tower; The distribution piping downstream of the scrubber; The deck water seal; The length and diameter of the inert gas distribution system. 28

100. Inert Gas Pressure Regulating Valve The Inert Gas Pressure Regulating Valve (pressure control arrangements) should be fitted to fulfil two functions: To prevent automatically any backflow of gas in the event of either a failure of the inert gas blower, scrubber pump etc., or when the inert gas plant is operating correctly but the deck water seal and mechanical non-return valve have failed and the pressure of gas in the tank exceeds the blower discharge pressure, e.g. during simultaneous stripping and ballasting operations; To regulate the flow of inert gas to the inert gas deck main. A typical arrangement is given in figure 9. 29

101. Figure 9 : Inert Gas Pressure Regulating Valve 30

102. The Inert Gas Pressure Regulating Valve is automatically controlled by means of a pressure transmitter and pressure controller. There are different arrangements for controlling the inert gas pressure in the inert gas main, i.e. : - Throttling the regulating valve; - Recirculating the inert gas to the scrubber; - Venting inert gas into the atmosphere. 31

103. The pressure of the inert gas in the inert gas main must be monitored. An alarm should be given when the pressure exceeds the set limit (SOLAS Ch.II-2). When the pressure in the inert gas main forward of the non-return devices falls below 50mm water gauge, an audible alarm should be given, or alternatively, the main cargo pumps should shut down automatically (SOLAS Ch.II-2). • Non-return Devices (SOLAS Ch.II-2). The Deck Water Seal and mechanical non-return valve together form the means of automatically preventing the backflow of cargo gases from the cargo tanks to the machinery space or other safe area in which the inert gas plant is located. 32

104. • Deck Water Seal (SOLAS Ch.II-2). This is the principal barrier. A water seal is fitted which permits inert gas to be delivered to the deck main but prevents any backflow of cargo gas even when the inert gas plant is shut down. It is vital that a supply of water is maintained to the seal at all times, particularly when the inert gas plant is shut down. In addition, drains should be led directly overboard and should not pass through the machinery spaces. There are three different types of Deck Water Seals, namely: 33

105. .1 A Wet type seal; .2 A Semi-Dry type seal; .3 A Dry Type seal. Wet type seal This is the simplest type of deck water seal. When the inert gas plant is operating, the gas bubbles through the water from the submerged inert gas inlet pipe, but if the tank pressure exceeds the pressure in the inert gas inlet line the water is pressed up into this inlet pipe and thus prevents backflow. The drawback of this type of water seal is that water droplets may be carried over with the inert gas which, 34

106. although it does not impair the quality of the inert gas, could increase corrosion. A demister should, therefore, be fitted in the gas outlet from the water seal to reduce any carry-over. Figure 10 shows an example of a wet type seal. 35

107. Figure 10: Deck water seal – Wet type. 36

108. GAS OUTLET WATER OVERBOARD WET SEAL (GAS ALWAYS PASS THROUGH WATER) WATER INLET INERT GAS INLET GAS PASS THR. DEMISTER INERT GAS BUBBLED THROUGH THE WATER

109. WATER INLET WATER OVERBOARD WET SEAL (GAS ALWAYS PASS THROUGH WATER) BACK FLOW OF GAS DUE TO LEAK IN ISOLATING VALVE EXCESS PRESS. OF GAS IN OUTLETPIPEWILL CAUSE A COLUMN OF WATER TO RISE IN INLET PIPE IN CASE OF BACK FLOW LOW LEVEL ALARM

110. Semi-dry type seal In this type of seal, instead of bubbling through the water trap the inert gas flow draws the sealing water into a separate holding chamber by venturi action thus avoiding or at least reducing the amount of water droplets being carried over. Otherwise it is functionally the same as wet type. Figure 11 shows an example of a semi-dry type seal. 37

111. Figure 11: Deck water seal – Semi-dry type 38

112. Water Overboard Water Inlet Gas Inlet Low Water Alarm WATER DISPLACED BY GAS PRESSURE Gas Outlet Venturi Semi dry Type Deck Seal Forward Flow

113. Hydrocarbon/inert gas leak past the non-return valves due to high gas pressure in the deck main line . Gas pressure acting on the surface of water in the outlet pipe would cause a column of water to rise in inlet arm. Water Inlet Water Outlet Semi dry Type Deck Seal Back Flow Venturi Low Water Alarm

114. Dry type seal In this type of seal, the water is drained when the inert gas plant is in operation (gas flowing to the tanks) and filled with water when the inert gas plant is either shut down or the tank pressure exceeds the inert gas blower discharge pressure. Filling and draining are performed by automatically operated valves controlled by the levels in the water seal and drop tanks and by the operating state of the hlowers. The advantage of this type is that water carry-over is prevented. The drawback could be the risk of failure of the automatically controlled valves which may render the water seal ineffective. Figure 12 shows an example of a dry type seal. 39

115. Figure 12 : Deck water seal – Dry type 40

116. OPEN SHUT Low Level Alarm Dump Valve Water Supply Level Control Drop Tank Auto Drain Valve Overflow Drain Gas Inlet Gas Outlet Vent Dry Type Deck Seal Forward Flow As inert gas is supplied ,The drain valve opens automatically Drain valve shuts automatically when the tank is dry Inert gas passes the seal without touching water Water drain out

117. Dry Type Deck Seal Level Control Vent Drop Tank Water Supply Dump Valve Low Level Alarm Auto Drain Valve Overflow Drain SHUT OPEN As inert gas plant is stopped, dump valve opens automatically Water drain from Drop Tank to Seal Tank Hydrocarbon/inert gas leak past the isolating valves due to high gas pressure in the deck main line. High gas pressure of back flow causes a column of water to rise in the inlet Back Flow And form a water seal OPEN

118. 41 Deck Water Seal Alarm For the Deck Water Seal, an alarm must be activated when the water level falls by a pre-determined amount, but before the seal is rendered ineffective. Heating arrangements should be provided to prevent freezing of the seal. Sight glasses and inspection openings should be provided on the deck seal to permit satisfactory observation of the water level during its operation and to facilitate a thorough survey. The sight glasses should be reinforced to withstand impact.

119. Deck Mechanical Non-Return Valve and Deck Isolating Valve As a further precaution to avoid any backflow of gas from the cargo tanks, and to prevent any backflow of liquid which may enter the inert gas main if the cargo tanks are overfilled, SOLAS Ch.II-2 requires a mechanical non-return valve or equivalent, which should be fitted forward of the deck water seal and should operate automatically at all times. This valve should be provided with a positive means of closure or, alternatively, a separate deck isolating valve fitted forward of the non-return valve, so that the inert gas deck main may be isolated from the non-return devices. The separate isolating valve has the advantage 42

120. of enabling maintenance work to be carried out on the non-return valve. Liquid-filled P/V Breaker One or more liquid-filled pressure/vacuum valves should be fitted (SOLAS Ch.II-2). These devices require little maintenance, but will only operate at the required pressure if they are filled to the correct level with liquid of the correct density. Either a suitable oil or a freshwater/glycol mixture should be used to prevent freezing in cold weather. Evaporation, ingress of seawater, condensation and corrosion should be taken into consideration and adequately compensated for. 43

121. The designer should ensure that the characteristics of the deck water seal, pressure/vacuum breakers and pressure/vacuum valves and the pressure settings of the high and low inert gas deck pressure alarms are compatible. It is also desirable to check that all pressure/vacuum devices are operating at their designed pressure settings. The operating principle of a liquid-filled pressure/vacuum breaker is shown in figure 13. 44

122. 45 Figure 13: Operating Principle of Liquid-filled Pressure / Vacuum Breakers

123. Inert Gas Operations On board oil tankers required to be fitted with an inert gas system, the system should be used during the full cycle of tanker operations. The cargo tanks should preferably at all times be inerted and have a tank atmosphere with an oxygen content not exceeding 8% by volume except when the tanks need to be gas-free. During normal operation of oil tankers, the following inert gas operations take place: - Inerting of empty gas-free tanks; - Inerting during loading and simultaneous discharge of ballast from cargo tanks; - ‘Topping-up’ during loaded and ballast sea voyages; 46

124. - Inerting during discharging and ballasting; - Inerting during tank cleaning; - Purging prior to gas-freeing; - Use of the IGS for gas-freeing. Inerting of empty gas-free tanks Inerting of empty gas-free tanks is shown in figure 14. Inerting of empty gas-free tanks should be continued till the oxygen content is reduced to below 8% by volume. Purge pipes/vents should be closed and the tanks pressurized with inert gas. When all tanks have been inerted, they should be kept common with the inert gas main and maintained at a positive pressure in excess of 100 mmWG during the rest of the cycle of tanker operation. 47

125. Figure 14: Condition: Inerting of tanks filled with air . 48

126. Inerting during loading and simultaneous discharge of ballast from cargo tanks See figure 15. During loading without deballasting, it is normally not necessary to operate the inert gas system. Figure 16 indicates this operation with stopped inert gas system. On completion of loading and prior commencement of loaded voyage, the IGS may have to be started and tanks pressurized to 300-600 mmWG. 49

127. Figure 15: Condition : Simultaneous loading and deballasting of cargo tanks with IGS in use 50

128. Figure 16: Condition : Loading or Ballasting with IGS stopped. 51

129. ‘ Topping-up’ during loaded and ballast sea voyages During the loaded and ballast sea voyages, the cargo tanks should be kept inerted with a positive pressure (above 100mmWG). The positive pressure may, however, be disturbed by several factors. The most common are: - leakages in valves and hatch covers; - change of pressure in the tanks due to temperature variations (i.e. day and night and sea/air temperature changes); - rolling, pitching and heaving in rough sea. 52

130. ‘Topping-up’ of the tank inert gas pressure may be done by starting up the inert gas system or by using a special ‘topping-up’ generator, if fitted. The volume of inert gas needed for this ‘topping-up’ operation is normally small in loaded condition. Figure 17 illustrates ‘topping-up’ of tanks . 53

131. Figure 17: Condition: ‘topping-up’ of tanks . 54

132. Inerting during Discharging and Ballasting Figure 18 shows the IGS in operation during cargo discharge. Figure 19 shows the IGS in operation during simultaneous discharge and ballasting. On completion of cargo discharge and stripping , and prior commencement of ballast voyage, the tanks should be pressurized to 300-600 mmWG inert gas pressure. 55

133. 56 Figure 18: Condition : IGS in operation during cargo discharge

134. Figure 19: Condition : IGS in operation during simultaneous discharge and ballasting 57

135. Inerting during Tank-cleaning The oxygen content in the tank atmosphere should always be checked before any tank cleaning is started. No tank cleaning, either with the cargo oil – Crude Oil Washing (COW) – or with water, should be started unless the oxygen content measured in the tanks is 8% by volume or less and inert gas pressure is possitive (above 100 mmWG). The conditions during tank cleaning with water are shown in figure 20. 58

136. 59 Figure 20: Tank Cleaning with water

137. Purging prior to gas-freeing When it is desired to gas-free a tank after washing, the concentration of hydrocarbon vapour should be reduced by purging the inerted cargo tank with inert gas. Purge pipes/vents should be opened to atmosphere and inert gas introduced into the tank until the hydrocarbon vapour concentration measured in the efflux gas has been reduced to 2% by volume (below the critical line of dilution with air) and until such time, as determined by previous tests on cargo tanks, has elapsed to ensure that readings have stabilized and the efflux is representative of the atmosphere within the tank. 60

138. Gas-freeing Gas-freeing of cargo tanks should only be carried out when tank entry is necessary (e.g. for essential inspection, maintenance and repairs). It should not be started until it is established that a flammable atmosphere in the tank will not be created as a result (purged with inert gas to below critical line of dilution with air). Gas freeing may be effected by pneumatically, hydraulically or steam-driven portable blowers, or by fixed equipment. In either case it is necessary to isolate the appropriate tanks to avoid contamination from the inert gas main. 61

139. When a large number of cargo tanks are required to be gas-freed (e.g. dry-docking etc.), the inert gas fans may be used as gas-freeing fans. IGS is generally fitted with a fresh air suction duct on the suction side of the fans (see 4a in figure 21). Gas-freeing can then be carried out by; shutting the boiler uptake valves (2), isolating scrubber (3), shutting the inert gas fans’ suction valves(4) and taking direct suction from atmosphere (4a). Fresh air will then flow into the inert gas main on deck. See figure 21: Condition: Gas-freeing with inert gas fans. Gas-freeing should continue until; the entire tank has an oxygen content of 21% by volume, a reading of less than 1% of LFL is obtained on a combustible gas indicator, and toxic gas, if any, is below its TLV. 62

140. Figure 21: Condition: Gas-freeing with inert gas fans. 63

141. Emergency Procedures In the event of total failure of the inert gas system to deliver the required quality and quantity of inert gas and maintain a positive pressure in the cargo tanks and slop tanks, action must be taken immediately to prevent any air being drawn into the tank. All cargo tank operations should be stopped, the deck isolating valve should be closed and immediate action should be taken to repair the inert gas system. In the case of tankers engaged in the carriage of crude oil it is essential that the cargo tanks be maintained in the inerted 64

142. condition to avoid the hazard of pyrophoric iron sulphide ignition. If it is assessed that the tanks cannot be maintained in an inerted condition before the inert gas system can be repaired, an external supply of inert gas should be connected to the system through the arrangements required by SOLAS as soon as practicable, to avoid air being drawn into the cargo tanks. In the case of product carriers, if it is considered to be totally impracticable to effect a repair to enable the inert gas system to deliver the required quality and quantity of gas and maintain a positive pressure in the cargo tanks, cargo discharge and deballasting may only be resumed provided that either an external supply of inert gas is connected to the system through the arrangements required by SOLAS, or the following precautions are taken: 65

143. The venting system is checked to ensure that approved devices to prevent the passage of flame into cargo tanks are fitted and that these devices are in a satisfactory condition. The valves on the vent mast risers are opened. No free fall of water or slops is permitted. - No dipping, ullaging, sampling or other equipment should be introduced into the tank. If it is necessary for such equipment to be introduced into the tank, this should be done only after at least 30 minutes have elapsed since the injection of inert gas ceased. All metal components of equipment to be introduced into the tank should be securely earthed. This restriction should be applied until a period of five hours has elapsed since injection of inert gas has ceased. 66

144. Inert Gas Generator schematic

145. IGG combustion system  The inert gas produced is perfectly acceptable for use during tank cleaning and line blowing, and when the ship is in the products trade, but it is not suitable for blanketing or padding the majority of chemicals. Such inert gas could contaminate the vapour space above the cargo or leave carbon deposits or acidic formations detrimental to the coating on tank walls.

146. Schematic process diagram with Inert Gas Generator, Refrigeration cooler and dryer.

147. Inert Gas Generator during final assembly.

148. R22 Compressor FW Condenser Inert Gas Generation

149. R22 Compressor FW Condenser Inert Gas Generation

150. Water Content at Dew point Temp

151. IG Control system

152. INERT GAS UNIT N2 RM IG plant and controls

153. 2.3.Inert gas Generators For gas- and chemical transportation the Inert Gas needs to be of high purity. For many applications oxygen levels of 0,5% or even 0,1% are required, in combination with a water dew-point of about -45°C and sometimes lower (-65°C). Also here, the burner is the heart of the system as the Inert Gas needs to be absolutely soot free in the first place. This is achieved with the Combustion system . When the gas leaves the generator, it has the right composition, but it is saturated with 100% water and has to be dried.

154. 2.3.Inert gas Generators The drying process takes place in two steps. In the first step of the refrigerant cooler, the gas temperature is lowered to 5°C which results in condensation of a great quantity of water. In the second stage the inert gas is dehumidified further in a double vessel type drying-unit using activated alumina or absorbent. The whole process operates under a pressure of about 0,3 bar(g). Low pressure, low dew-point Inert gas Generators are typically used on CHEMICAL CARRIERS with refrigerated cargoes carriers. Enraf Smit Gas Systems is one such supplier in this segment.

155. 2.3. Inert Gas system Vessel is provided with one Inert gas generator. The unit burns low sulfur diesel oil to produce 5600 SCFM of IG. Inert gas system is used for inerting cargo tanks & pipelines for Gas freeing operation and for inerting Hold spaces. Gas Volume Discharge pressure Dew point O2 content CO H2 SO2 + NO2 NO + NO2 CO2 N2 Soot 5 PSIG -45 deg C 1 % Max 0.5 % Max (100 ppm) 500 PPM Max 50 PPM Max 300 PPM max 15 % Approx Balance (80 to 85 %)

156. Refrigerant type inert gas cooler.

157. IG Plant

158. IG Plant

159. IG Plant O2 analyzer

160. IG DRYER IG NRV & CONN TO CARGO IG drier & NRV connection to cargo

161. Dehumidifier

162. Desiccant type dryer of 15000 Nm3/h at a dew-point of -65C.

163. IG plant/Dry air unit The dew point of dry air produced by the unit shall equal that specified for inert gas. The combustion chamber of the inert gas generator shall be horizontal or near horizontal, so as to avoid potential pollution during start up and in the event of flame failure. No refractory linings shall be employed. The plant shall be arranged for fully automatic operation. Starting shall be performed under local control and equipment shall be provided to allow remote control and monitoring from the cargo control room.

164. IG plant/Dry air unit Where regenerative dryers are installed, facilities shall be provided to allow regeneration in the absence of a supply of steam in order to allow the unit to produce dry air in the event of the vessel being laid up. Where refrigerated dryers are installed, Refrigerant 410A or other non-ozone depleting refrigerant shall be used.

165. DRY AIR SYSTEM To Prevent icing and maintain a non corrosive atmosphere inside the tank To aerate the tanks with dry air. The air supplied is dried in 2 stages Drying is done at 5 deg. C. by condensing the atmosphere and draining to the bottom of the heat exchanger. Activated Alumina removes most of the moisture giving a dew point of -25deg. C. Use of blowers further reduce the dew point to -40deg.C

166. Air drying system Old silica/Alumina become powder and cause dust problems to cooling systems. Timing of purge sequences Symptoms of problems

167. N2 System An arrangement by which the requirement for an inert gas generator is deleted and replaced by larger capacity nitrogen Generator may be considered as an option. The inert gas plant with associated scrubber, cooling system, fuel system, fire protection etc., replaced by a simple air dryer unit with blowers providing dry air at Dew Point 45°C at atmospheric pressure. A recent development for producing nitrogen for inerting on gas ships is the pressure swing adsorption method which uses compressed air and a molecular sieve adsorbent. This method produces nitrogen of at least 97% purity with just traces of moisture and carbon dioxide and so could well be an alternative method of inert gas generation on chemical tankers of the future

168. N2 System The total capacity of the nitrogen generators increased so as to provide sufficient nitrogen flow at 95% purity for cargo tank inerting operations. The large capacity nitrogen plant will allow nitrogen to replace instrument air throughout the vessel, reducing duplicated pipe work and eliminating the need for separate instrument air receivers, instrument air dryers etc.

169. N2 System Nitrogen IGG systems produce nitrogen gas from air by means of membrane separators. Each separator consists of a bundle of hollow fibers in a cylindrical shell. As compressed air is fed into the separator OXYGEN, CARBON dioxide and water vapor permeate through the walls of the fibers faster than the nitrogen, leaving behind a product stream of super-dry nitrogen.

170. N2 System The nitrogen leaves the separator at essentially the same pressure as the incoming feed air. The secondary oxygen rich stream is by-passed to atmosphere at nearly atmospheric pressure. A standard skid mounted system consists of a number of separators, feed air filters, feed air heater, piping, instrumentation and controls for automatic unattended operation

171. N2 GENERATORS USE ON BOARD FOR MAINTAINING POSITIVE PRESSURES IN INTER BARRIER SPACES INSULATION SPACES SUPPLYING NITROGEN TO ANNULAR SPACES ON MOSS SHIPS PURGING EQUIPMENT AND PIPELINES SEAL GAS FOR EQUIPMENT – HD AND LDs NITROGEN VENT MAST FLAME SNUFFING OPERATING PRINCIPLE MEMBRANE USED TO SEPARATE AIR INTO NITROGEN AND OXYGEN DUE TO VARYING PERMEATION RATES THE GASES SEPARATE COMPRESSED AIR IS FED INTO A BUNDLE OF MEMBRANES AND OXYGEN AND OTHER GASES ARE VENTED BUFFER TANKS PROVIDED FOR STORAGE

172. N2 Pressurization and purge N2 system is used for the following purposes: Purging the cargo tank hold insulation space and maintain clear of vapor Maintain the cargo compressors, heaters, pumps etc at dehydrated condition by purging with N2 Purging cargo piping Purging gas piping (GNG) to ship’s boilers To supply gaseous nitrogen sealing gas for high & low duty vapor compressor seals. Vent riser fire extinguishing There are two liquid nitrogen storage tanks (In certain case only one tank but total capacity as mentioned)(6545 US Gallons at -320 F) which are filled by liquid N2 from shore connections or used as a storage for GN2 generated in GN2 generator in engine room.

173. N2 to cofferdams and empty ballast tanks The Insulation Spaces are to be pressurized with Inert gas. Use vacuum pumps to remove air and moisture, evacuate to about 200mb Pressure in tank should always be higher than secondary barrier space pressure Pressure in Secondary barrier space should be slightly higher than primary barrier space Monitor regularly the pressure pre-set Levels for loaded and ballast conditions.

174. IBS Pressure Control

175. IS Pressure Control

176. Nitrogen Supply to IBS and IS Spaces

177. Nitrogen Supply to IS

178. Detail of Nitrogen Supply to IS

179. Interbarrier Space Inerting - NO96

180. Nitrogen Supply to IS – NO96

181. Nitrogen System Liquid N2 is vaporized and warmed to ambient temperature Nitrogen header supplies GN2 by 1 inch line to void space N2 makeup supply header (three valves located outside each cargo tank cover at main deck level) which supplies low pressure N2 to annular insulation spaces around each of cargo tank through low pressure regulator valve.

182. Nitrogen System The regulator valve maintains space press I inch of water above cargo tank hold (Moss type) N2 flows through an orifice (0.11 inch dial) plate from low pressure regulator to lower & upper annular spaces. The orifice plate protects the annular insulation space from over pressurization. Gas may be sampled with in the upper & lower hemisphere of insulation system by two valves located at main deck level outside tank covers.

183. N2 line & barrier space relief valves GENERAL : As per the IBC Code, all cargo tanks should be provided with a pressure relief system appropriate to the design of the cargo containment system and the cargo being carried. Hold spaces, interbarrier spaces and cargo piping which may be subject to pressures beyond their design capabilities should also be provided with a suitable safety relief system.

184. N2 line & barrier space relief valves The pressure safety relief system should be connected to a vent piping system designed so as to minimize the possibility of cargo vapor accumulating about the decks, or entering accommodation service and control station spaces, and machinery spaces, or other spaces where it may create a dangerous condition.

185. N2 generator Nitrogen produced by the unit shall meet the specification of the containment system designer but, in any case, shall be dust and oil free and shall meet the following minimum quality requirements: O2 . 3% volume Dew Point .65°C at atmospheric pressure The plant shall operate fully automatically and shall be arranged for remote control and monitoring from the cargo control room. Discharge flow shall be diverted if the oxygen content exceeds 3% by volume.

186. N2 generator Two equally sized nitrogen generator plants of the membrane permeation type are usually installed within the machinery casing with direct access to the machinery space and to the deck. The capacity shall be such that one unit shall satisfy all normal service requirements, including normal loading, with a 50% margin. Periods of exceptionally high demand, such as the initial cool down of the cargo system from ambient conditions may be satisfied by two units operating in parallel. The plant should be provided with a buffer tank of sufficient capacity to ensure that the plant shall not start more than once per two hour period in normal operation at sea. Feed air may be supplied to the nitrogen generator from the engine room compressed air system.

187. N2 RM2 N2 TANK N2 Control & tank

188. Membrane Separators

189. Nitrogen Separators

190. INERTING LINE DIAGRAM

191. INERTING OPERATION IS COMPLETE WHEN HC CONTENT LESS THAN 0.5 % BY VOL ALL PUMP COLOUMNS AND PIPELINES ALSO TO BE INERTED ENSURE PROCESS HAS MINUMUM TURBULENCE MONITOR TANK PRESSURES, DO NOT ALLOW THEM TO FALL BELOW THE PRESSURE DIFFRENTIAL REQUIEMENT WITH THE BARIER SPACE

192. AERATION DRY AIR INTRODUCED INTO TANKS VAPOUR HEADER INERT GAS REMOVED FROM THE TANK VIA THE LIQUID LINES OPERATION COMPLETE WHEN 21% OXYGEN IN TANKS Carbon Monoxide CO 50 PPM (max) Carbon Dioxide CO 2 5000 PPM (max)

193. Aerating points of operation For aerating, gas replacement Is carried out by the diffusion method because the difference between the specific gravities of air and IG is small. In parallel with aerating, the gas in the hold spaces is also vented into the air, lowering the pressure in the hold space to about atmospheric pressure. Attention should be given to the difference between the pressures of tanks and hold spaces. While aerating a tank, gas freeing is carried out for the pipelines leading into the tank, with the valves near the dome and the safety hand valves opened. For cargo gears in which inert gas may be remaining, the gas freeing operation should be carried out by feeding air, in parallel with aerating operation.

194. During the aerating operation, the O2 concentration should be measured periodically. Gas freeing a tank progresses relatively quickly until the O2 concentration reaches about 18%, but gas freeing tends to be slow when O2 concentration exceeds 18%. Each concentration of O2, combustible gas, CO2 and CO is measured to adjust it finally to the docking standard. Aerating

195. Target figure for aerating O2 concentration: 20 volume % or more Combustible gas concentration : Less than 0.095 volume % CO2 concentration: Less than 0.5 volume % CO concentration: 50 ppm or less The standards for docking chemical ships safely is specified by the Japan Shipbuilding Industries Association

196. 245 Combustion air fan IG Genera-tor Pressure/Vacuum Breaker Oil Fuel Pump Deck water seal INERT GAS SYSTEM (Source: SMIT OVENS)

197. 246 N2 MEMBRANE GENERATOR (Source:DOW)

198. Fire prevention and fire fighting If fire is still not coming under control then there is a danger of flash over and roll over. Assess the situation review the fire risk assessment and if necessary call back the attack and take head count and check for casualty. If there had been casualty before take precaution before mount rescue mission without unduly risking the life of the fire fighters. Prepare to deploy full flooding fixed fire installation what ever is installed on ships.

199. Tanker Pipeline Systems Direct Line Ring Main Free Flow Cruciform

200. Direct Line system It consists of lines running longitudinally in the centre tanks and branching out to bell mouths in the centre and wing tanks. The system is uncomplicated and found on some crude carriers

201. DIRECT LINE

202. Advantage: Quick loading & discharging. Short pipe line. Less bend. Less loss of pressure due to pipe line friction. Direct line to provide better suction. Time of washing the line is short. System is cheaper than the other system. Leak is minimized. Easy to operate so less training is required. It is easy to separate each cargo.

203. Direct Line Advantages:- Relatively Fast Cheaper Good Segregation Line Wash fast Less Maintenance DISADVANTAGES:- NOT SO VERSATILE LINE WASHING INTO DESIGNATED TANKS

204. DIRECT LINE

205. Direct Line (Loading) Open Cargo Tank Valves Open Crossover Valves Open Drop Valves Open Bulkhead Masters Open Manifold Valves When all valves confirmed open Ship and shore checks complete Request commence slow loading

206. Disadvantage: In case of leaking the control of leakage is difficult. This system is very inflexible.

207. Direct Line (Discharge) When all valves confirmed open Ship and shore checks complete Request commence de-bottom Open Risers Open Pump Suction valves Open Bulkhead Masters Crack Open Pump discharge valves Open Manifld Valves Start 1 st Pump at slow speed When Deck, Pumproom and overside checks completed & Shore receiving Start 2 nd Pump at slow speed Open Crossover Valves Open Cargo Tank Valves

208. DIRECT LINE

209. Direct Line (Loading)

210. RING MAIN SYSTEM

211. Ring-main systems It is also called the circular system. This type of piping system provides for the handling of several different types of oil. A particular tank can be pumped out either by a direct suction line or through another line by use of a cross-over. The system is very versatile.

212. Ring-main systems The pipeline system illustrated above in Diagram 1 is better suited to the centre line bulkhead type of ship. Each tank or oil compartment has two suctions — one Direct suction and one Indirect suction. The direct suctions for the port tanks are all on the port cargo line, and feed the port cargo pump. The indirect suctions for the port cargo tanks feed the starboard cargo line and the starboard cargo pump.

213. Ring-main systems Master valves are provided on each line between the tanks, so as to isolate each tank from the other when necessary. This particular vessel is not fitted with a stripping line and pump. This type of pumping system providing for the handling of several different types of oil was a natural development from the earlier types which were only suitable for one grade of oil. To drain the oil from the main tanks it was necessary to list first one way, and then the other, so as to keep the strum covered and to help the flow of oil towards the suction.

214. RING MAIN Advantages Versatile Disadvantages: Erosion @ bends Expensive High maintenance Line washing difficult Relatively slow load/discharge

215. RING MAIN Diagram 2 shows a vessel fitted with a Circular Line or Ring Main but adjusted for the twin bulkhead type of vessel. This ship is also fitted with a stripping system. Inspection of the pipeline system shows that the pipeline travels around the ship in the wing tanks, crossing over from one side to the other.

216. RING MAIN Each wing tank has a suction on the line which passes through it. The centre tanks have two suctions, one on either side leading to the port and starboard lines respectively. It will be noted that the master valves provide separation between the tanks as in the earlier system. When the level of the oil in any particular tank has fallen to a foot or less, the main pumps are switched to another full tank, and the stripping pump is brought into operation.

217. Ring main system - Advantage: In this system any tank can be discharged by any pump. Thus different grade of the cargo can be loaded.

218. RING MAIN

219. RING MAIN

220. RING MAIN

221. Disadvantage: Is not flexible. One grade is dischargeable if more risk of contamination exists. Risk of overflow exists if level of all tank doses not carefully monitoring.

222. Free-flow system In this system, the oil flows freely into the aft most tanks when the interconnecting gate valves are opened. Main suction bell-mouths in a full free flow tanker will only be provided in the aft tanks. However, each tank is generally provided with a small stripping line. This system has the distinct advantage of having lesser and less complicated piping system in the tanks and is suitable for large tankers which usually do not carry many grades of oil. Obviously, the flexibility of operations is comparatively less as compared to other piping systems. Some ships are also designed as part free flow i.e. free flow system only between certain tanks, which is a hybrid or cross between a full free flow system and a ring main system.

223. Free Flow Advantages Fast load/discharge Simple Disadvantages: Poor segregation Vessel usually requires a pipeline system as well

224. Free flow system - Advantage: Main pipe line is not used for discharge. Less pipe line. Less bend. Less friction & more pressure cause very high discharge.

225. FREE FLOW SYSTEM Open Centre Cargo Tank Valves Open wing tank cargo valves Open Main Tank Suction Valves Open Cargo Pump Suction Valves Open Manifold Valves Crack Open No.1 Pump Discharge Valve X When Ship shore checks completed Start No.1 Cargo Pump at slow RPM and De-bottom When deck and overside checks completed Ship/Shore ready continue running up pumps X X Crack Open Discharge valves & Start remaining pumps

226. FREE FLOW SYSTEM

227. Disadvantage: Is not flexible. One grade is dischargeable if more risk of contamination exists. Risk of overflow exists if level of all tank doses not carefully monitoring.

228. Points to Pounder for all types of Pipe lines THE FREE FLOW SYSTEM THE DIRECT LINE SYSTEM THE RING MAIN SYSTEM Used on large crude Carriers Used on VLCC Used on Product Carriers Carry only one garde Of cargo Carry two or three grade Of cargo Carry several Different products Large gate valve built in The bulkhead Simple lines leading in the Tanks   Stern trim cause the oil To flow to the Aftermost tank Due to straight length of Pipeline, there is better Suction & less loss of Pressure Due to the number of Bends, joints and valve It take longer time Suction main cargo pump Situated in aft Fewer valve & bends Means less erosion & leak Less maintenance Required. Due to the number of Bends, joints and valve Means more erosion & Leaks More maintenance Required Thorough washing of line is Not possible unless the Washing are flushed into The tank & discharged From there Thorough washing of Line is possible without Flushing into the tank   Due to fewer valves leaks Are difficult to control Valve    segregation not Provided  Required two valve Segregation Between products    The initial cost of fitting Is less than ring main System The initial cost of Fitting is higher

229. Valves:   The valves used in tankers for cargo can be either butterfly valves, gate valves or sometimes rarely even globe valves. At pump discharges, a non-return flap valve is usually fitted. A detailed description of the merits and demerits of each type of valve will be outside the scope of this course.

230. The valves may be hydraulically, pneumatically or manually operated. Manual valves can have an extended spindle to enable operation of a tank valve from the deck. It is important to note that the valve closure period is deliberately slow to avoid surge pressures. In the hydraulic and pneumatic system, the timing is normally pre-set to a safe limit and rarely requires to be adjusted. Valves:  

231. However, in manually operated valves the closing time is regulated by the operator. Dangerous surge pressure can build up which can rupture a pipeline or a part of it even in a remote location. The higher the fluid pressure in the pipeline, the greater will be the risk of rupture and pollution. The most critical period is the last 25% when closing the valve or the first 25% when opening it. One can actually hear the liquid squeezing through the valve. The rate of closure during this period should be especially slow and controlled. Valves:  

232. Load and Discharge # No3 Diesel Jet Fuel Petrol # No2 # No1

233. 38 6. Cargo Systems Centrifug a l carg o pum ps with a doubl e entry impeller have largely replaced r eciprocatin g pump s in oi l tankers . These pump s a r e cheaper, have no suction or delivery valves, piston s , ring s , etc and therefore require less maintena n c e . The compac t centrifuga l pum p ca n b e mounted horizontally o r vertically in the pum p room with a turbi ne , o r in some ships electric motor, drive from the engi ne room. The drive s haf t pas s e s through t h e engin e room bulkhea d via a ga s -tight seal . Rate of pumpin g is hig h (2 6 m3 /hr) unti l a low le v e l is reached, when loss o f hea d an d impeded flow through frames an d limber hole s makes slowdown in the rate o f pum ping necessar y if us e o f a small stripping pum p is to b e a voided. Systems such a s t h e Worthin gto n- Simpson ' Vac -Strip ' enable a faster genera l rate o f di s charg e to b e maintain e d while reducing the rate o f di s charg e a t lower tank levels to allow for drai ning . T ues day, Febr ua ry 10 , 2015

234. o 39 Vac-Strip System Suction from the carg o tank is taken through a separator tank to the pum p inlet an d discharg e from the pum p is through a butterfly valv e t the dec k main .When carg o tank level drop s an d flow is less than the rate o f pumping , liquid level in the separator tank will also reduce and this will b e registered b y the level monitoring devic e . The latter will automatically start the vacuu m pum p an d caus e the openin g o f a diaphrag m valv e to allow passag e o f vapou r to the vacuu m pump from the separator tank. General accumulatio n o f vapou r in the suction tank will caus e the same result . The vacuu m pum p will prime the system b y re m ovin g ai r o r vapo u r . Ris e o f liquid in the sepa r ator tank will caus e the vacuu m pum p an d vapou r valv e to b e closed dow n . Continuing dro p in liquid level du e to slow draining necessitate s a slowdown in the pumpin g rate an d this is achieve d by throttling o f the main pum p butterfly discharg e valv e . Valv e closur e is controlled b y the level monitoring device . The butterfly valv e ca n also b e han d operate d . Throt t ling is no t harmfu l to the centrifuga l pum p in the short term. The primer/vacuu m pum p drive n b y a n electric motor in the engin e room is o f the water ring type 6 . Cargo Systems

235. Vac-Strip System T h e s e parato r t a n k works lik e a re s ervoi r f e e ding t h e pu mp with liqui d . T h e liquid level inside t h e separ ator t a n k will fall w h e n t h e leve l i n th e cargo tank is g etting l o wer t h a n t h e height o f t he separ ator t a n k. T h e voi d spa c e abov e t h e liquid inside t h e s epar at o r t an k will inc re as e . I n t his sta g e , fall ing pu mp pre ss ur e s h oul d b e ob s erved befo re t h e vac uu m sys t e m is activated . At a fixed limit o n t h e s eparat o r t a n k , t h e vacu u m p u mp will sta r t cr eatin g a va cu u m in t h e voi d s p ac e a bove t h e liq ui d . T h e val ve b et we e n t h e s e parato r t ank an d th e vac u u m t an k will ope n an d t h e liquid will b e s uc ke d into t h e s eparat o r t a n k beca u se o f the vacu u m . At t h e s a me ti m e , th e d el iver y v a lv e is auto m atica l l y (or m a n u a ll y ) t h rottle d . T hi s is done to giv e time for the separator tank to refill itself . T ues day, Febr ua ry 10 , 2015 285 6 . Cargo Systems

236. C o n ve nt io na l O i l T an k er 342 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

237. Paral l el operation of centrifugal pumps When equal pump s ar e run in parallel , the delivery hea d for the system will b e equa l to the delivery hea d for on e pump . The capacity , however , will increase in proportion to the numbe r o f pumps . If, for instance one pum p ha s a capacit y o f 1,33 m3/hr. a t a delivery hea d o f 8 8 meters, two pump s in paralle l will delive r 2,66 m3/hr. an d three pum p s 3,99 m3/h r . a t the same head. T ues day, Febr ua ry 10 , 2015 287

238. Paral l el operation of centrifugal pumps To plot in pump cur v e “B” add the delivery amo u nt of the two pump s a t the differen t deliver y heads. As sh o wn in cur v e “A” the delivery at 20mlc . i s 1,770 m3/h o ur, poin t 1 . P lo t a new poin t a t 20mlc . (1,77 + 1,77 ) = 354 m3/h o ur , poin t 11 . I n the sam e way , we are plotting the value s according to the table above . When al l the value s are plotted , a new cur v e is drawn through the plotted p oints, curve “B”. Where the new cur v e i s cros s ing the syste m cur v e, the deliver y amo u nt an d delivery head for two pump s in paralle l operation wil l b e read. The sam e procedure stand s for 3 or 4 pumps i n paralle l o peration. Starting pum p number 2 wil l not doubl e the capacity becaus e a higher vol u me of f lo w creates higher dynami c resistance. The increase i n capacity will then b e relatively les s for each pum p a d de d . T ues day, Febr ua ry 10 , 2015 288

239. Pump Calculat i ons  Case Study On the exampl e curv e in this chapter , a curv e is draw n for on e pum p which runs with a fixed revolution. the curv e for the pipe , which consist s o f static and dynami c backpressure . The static backpressur e is cause d b y the difference betwee n the shore tank’ s liquid level an d the vess e l’ s carg o tan k ’ s liquid level. Friction resistance in valves , bends , pipes , et c causes the dynamic backpressure in point “A” (point of intersection), the pump delivers 1,560m3/hou r a t a delivery hea d o f 5 8 mlc . The oil’s density in the exampl e is 820kg/m3 . Out o f this information, it is possible to find ou t what 58mlc. correspond s to in pumpin g pressur e (manomet er pressure ) b y us e o f the following formula: T ues day, Febr ua ry 10 , 2015 289

240. Pump Calculat i ons  Case Study p = ρ x g x h p = pum p pressure ρ = the liquid’s density - 820kg / m3 g = the earth’s gravity acceleration - 9,81m/s2 h = delivery hea d - 58mlc. The value s use d ar e just for this example . The denomination , which appears , is calle d Pasca l (Pa). 100,00 P a is equa l to 1bar. Calc u late the man o met e r pressu r e: p = ρ x g x h p = 820kg / m3 x 9,81m/s 2 x 58mlc. p = 466,56 3 Pa. p = 4, 7 bar . (4,66563). T ues day, Febr ua ry 10 , 2015 290

241. Pump Calculat i ons  Case Study The dynami c backpressur e may change , i.e. when throttling on the pump’s delivery valve . In this example, the discharg e rate will b e reduced to 1000 m3/h. Choose to do so by throttling the pump’s delivery valve, an d when doin g so, calculat e the manomet er pressure. First, draw a ne w curv e (see the dotte d curve ) which crosse s the pum p curv e a t a delivery rate o f 1000m3/h, which creates the new intersection point “B”. From the point of intersection “B”, a horizontal line is draw n o n the left side o f the curve . The ne w delivery hea d is 9 8 metres. With the same formula a s befor e the man o met e r pressu re is calculated : p = ρ x g x h p = ρ x g x h p = 820kg / m3 x 9,81m/s 2 x 98 p = 788,33 1 Pa P = 7, 9 ba r (7,88331bar) T ues day, Febr ua ry 10 , 2015 50

242. Pump Calculat i ons  Case Study Out o f t he T ues day, Febr ua ry 10 , 2015 292 s ame formula , it is also po ssibl e to the calculat e t h e d e liver y he a d b y re ad ing m a n o me te r pres sur e. An exampl e using th e s a m e curv e diagram , th e m ano me te r pres sur e is 6, 3bar which compare s to (6,3 x 10 ,000) = 630,00 Pa. Calculate th e deli ver y h e a d b y tu r nin g t h e for m ula p = x g x h , to: h = p : (ρ x g) This will giv e following delivery head: h = p : ( ρ x g) h = 630,00 P a : (820kg/ m 3 x 9,81m/ s 2 ) h = 78 ,3 mlc.

243. B a r r e l - t y p e ca r g o p um p The pu m p wit h doubl e ey e i n let . T h e pip e co nn ec ti o n s i n b o tt o m h a l f of cas in g h as tw o ex t er n al b ear in gs a b ove th e i m p e ll e r , th e u pp er o n e t a k es a l l th e h yd rau l i c t hr u st a n d th e l o w er act as a radial lo ad be ar i n g . T h i s p u mp has s o me a dv an t a ge s ove r i t s cou n te r par ts : I m p e ll er can b e s it ed l o w er i n th e p ump roo m th us i m p r ov in g suc ti on co nditi o n s a n d r e d uc in g s t r ipping ti me, R emoval of i m p e ll er with out di s t u r bin g pip e j o int s . E as i er access t o b ea tin gs a n d s h a f t seal with out remo val of ro t a tin g e l eme nt s. 343 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

244. I n d uce r I nd ucers are some ti mes fitt ed t o ce nt r if ugal p ump i m p e ll er s h a ft s at suc ti o n . T h e i r p u r p os e i s t o e n su r e th e su pp l y of f l u i d t o th e i m p e ll er i s at su ffi c i e n t p ress u r e t o avo i d cav it a ti on at i m p e ll er suc ti on ( l ess N P SH re q) , i. e. i t e n a b l es th e p ump t o o p era t e wit h a l o w er n et p os iti ve su pp l y h ead ( N P SH av ) . 344 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

245. S u b me r ge d p um p T h e S u bm e rg e d e l e c t r i c m o tor d r i v en p u m p r e st s o n a s p r in g c a r t r i d g e whi c h cl o s e s when t he p u m p i s r ais e d a nd s ea l s o f f t he t ank fr o m t he c o l u m n C he mica l , L P G, or m ult i -pr o du ct t a nker : a s ep ara t e pu mp is si te d in e ach t a nk . Pu m p s d riv e n th ro u gh l i n e s h af t i n g co uple d t o hyd ra ul ic mo t or on de ck (dee p well , si n g l e or m ult is t a g e or s ub m e rg e d pu m p s ele c t ric a ll y or hyd ra ul ica l l y d riv en ) T h e Sub m e rsi bl e pu m p s el imi n a t e l i n e s h aft be ari n gs, a n d g l a n d pr o ble ms bu t e x pen si v e pr o ble ms co ul d occ u r du e t o hyd ra ul ic f lu id le a k age i nt o th e cargo a n d vice - v e rs a . 345 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

246. L P G P et ro leu m hyd roca rb on p ro du c t s s u ch as Pr o p a n e a n d B u t a n e , a n d m i xt u r es o f b o t h h ave been ca te gor i s e d b y th e oil i ndu s t ry as LPG . T h e most im p or t a n t p ro pe r t y of L P G is th at it is s u i t a bl e for be i n g pr essu r ised i n t o l i q uid f o r m a nd t ra n s p or t e d. . At l east on e o f t he f o ll o wi n g c on d i t i on s nee d t o b e comp l i e d w i th , for t ra n s p or t a t i o n of L P G: T h e gas s h o ul d b e pr essu r ised at a m b ie n t t e m p e r a t u r e . T h e gas s h o ul d b e fu ll y r ef r ige r a t ed at i t s b o i l i n g p o i n t . B oi l i n g p oi n t of L P G ra n g e rs fr o m - 30 de gree C el si u s t o - 48 de gr e e C el si u s. T h is co nd i t ion is ca lle d f ull y - r e frig e r a t e d co nd i t io n . T h e gas m u st b e se m i -r ef r ige r a t ed t o a red u c e d te m per a t u re a n d pre s s u ris ed O the r gases s u ch as a mmon ia, e t h yl e n e a n d pr o pyl e n e are a l so t ra n s p or t e d in l i que fi e d form in L P G carri e rs. E thylene , h o we v e r , h as a l o we r b oi l i n g p oi n t ( - 140 de gr e e C el si u s) th an o the r L P Gs. Hen ce it m u st b e carri e d in se m i -r ef r ige r a t ed o r fu lly-r ef r ige r a t ed c on di t i on s. 346 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

247. L NG N at u r al g as f r om w h i c h im p u r i t i e s l i k e su l p h u r a nd c a r b o n -d i o x i d e h a v e b ee n r em ov e d , i s c a ll e d L ique f ie d N at u r al Gas. A f t e r r em ov al of im p u r i t i e s, i t i s c oo l e d t o i ts bo i l in g po in t (-16 2 d eg r e e C e l s iu s ) , at or a l m ost at at m osp h e r i c p r e ss u r e. N o t e h e r e , t h at un l i k e L P G, L N G i s c oo l e d t o l o w t e m pe r a tu r e s b u t n o t p r e ssu r i s e d mu c h a b o v e a tm o s p h er i c p r e ssu r e . T h i s i s w h at m a k e s t h e d e s ig n of LN G c arr ie rs s l ig h t l y d i f f e r en t f r om L P G c ar rie rs. LN G, at t h i s c o n d i t i on i s t r a n spor t e d as l iqui d me t h a ne . 347 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

248. NG t r an s p o r t LN G co n s i s t s ma in l y of m et hane ( C H 4 ) , wit h m in o r amou nt s of o th er hyd ro carbo n s ( e th a n e, p ro p a n e, b u t a n e a n d p e nt a n e ) . B y l iq ue fyin g th e me th a n e gas, LN G t a k es up o n l y 1 / 600 t h of th e vo l ume of n a t u ra l gas i n it s gaseous s t a t e, whi ch mea n s th e gas can b e di s t r ib u t ed arou n d th e w or l d more e ffi c i e nt l y . B y com p ar i so n , com p resse d n a t u ra l gas ( C N G) t a k es up a r ou n d 1 / 100 t h of th e vo l ume of n a t u ra l gas i n it s gaseous s t a t e, d e p e ndin g on th e ac t ual p ress u re. 348 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

249. T an k s t y p es 1 . I n t egr al T a n ks T h ese are th e t a nk s th at f o rm a pr i mary s t r uctu r al part o f t he sh i p a n d are inf l ue n ced b y th e l oa d s com in g o nt o th e h u l l s t r uc t u r e. T h ey are ma in l y used f o r c as e s w h e n L P G i s t o b e c arr i e d at co n d i t i o ns clo se t o a t m o sph e r i c co n d i t i o n , f o r exam p l e – B u t a n e. T h at i s b ecause, i n thi s case, th ere are n o re q u i reme n t s f o r ex p a n s i on or co nt r ac ti on of th e t a n k s t r uc t u r e. 2 . I n d e p en d en t t a n ks T h ese t a nk s are s elf- s upp or t i ng i n n a t u r e, a n d th ey d o n ot f o r m an int eg r al p a r t of th e h u l l s t r uc t u r e. H e n ce, th ey d o n ot co nt r ib u t e t o th e overa l l s t re n g t h of th e h u l l g i r d e r . A cco r d i ng t o I GC Code , C h a pt er 4 , ind e p e nd e n t t a nk s a r e ca t ego r i sed int o t hr e e ty p e s: T y pe ‘ A ’ t an ks T y pe ‘ B ’ t an ks T y pe ‘C ’ t an ks 349 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

250. T an k t y p e s 1 . T ype ‘ A ’ ta n ks T h ese t a nk s are d es i g n ed us in g th e t ra diti o n al me th od of s hi p s t r uc t u r al d es i g n . L PG at n e a r - a t m o sph e ri c co n d i t i o ns o r LN G can b e ca rr i ed i n th ese t a nk s. T he de s i g n pr e ss u r e o f T y pe A t an k s i s le ss t han 700 m ba r . T he I GC Cod e s p ec ifi es th at T yp e ‘ A ’ t a nk s must h ave a s eco n d ary b arr i e r t o co nt a i n a n y l ea k age f o r at l east 15 d a y s. T he s eco n d ary b arr i e r must b e a com p l e t e b arrier of such ca p ac it y th at i t i s su ffi c i e n t t o co nt a i n th e e nti r e t a n k vo l ume at a n y h eel a n g l e. 350 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

251. T y p e ‘ A ’ tan k s The a b ove fi gu r e s h o w s h ow th e a lu m i n i u m t ank s t r uc t u r e i s n ot int eg r a t ed t o th e inn er h u l l of th e me th a n e carrier b y mea n s of a n y me t al co nt ac t . T h e inn er h u l l p l a tin g a n d a l um ini um t a n k p l a tin g a r e s e para te d b y l a ye r s co ns i s t i ng o f t i m be r , gl ass f i b r e , and bal sa pan el s f o r i ns ul a t i o n f rom ex t er n al t em p era t u re s . T h e b a l sa p a n e l s are h e l d t oge th er b y p l yw ood on b o t h f aces whi ch are sea l ed us in g P V C f oa m sea l s. A n in ert s p ace of 2 o r 3 mm se p arates th e inn er g l ass fib r e l a y er f ro m th e a l um ini um t a n k p l a t e. T hi s s p ace i s p ro v id ed f o r in su l a ti on a n d a l so a ll o w s ex p a n s i on a n d co nt ra c ti on of th e t a n k s t r uc t u r e. Th i s typ e of n o n -welde d i n teg ra t i o n ma k es thi s t a n k s t r uc t u r a ll y ind e p e nd e n t i n n a t u r e. 351 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

252. T y p e ‘ B ’ tan k s The most common arrange m e n t of T yp e ‘ B ’ t a n k i s K v a e rn e r -Mo ss Sph e r i c al T an k . T h e t a n k s t r uc t u r e i s sph e r i c al i n s h a p e, a n d i t i s so p os iti o n ed i n th e s hi p ’ s h u l l th at o n l y h a l f o r a g rea t er p or ti on of th e s ph ere i s u nd er th e ma i n d eck l eve l . T h e ou t er su r f ace of th e t a n k p l a tin g i s p ro v id ed wit h ex t er n al in su l a ti o n , a n d th e p or ti on of th e t a n k a b ove th e ma i n d eck l evel i s p ro t ec t ed b y a w ea th er p ro t ec ti ve l a y e r . A ve r t i c al tubul ar s upp ort i s l ed f ro m th e t op of th e t a n k t o th e b o tt om, whi ch h ouses th e pipin g a n d th e access r u n gs. A s ev id e n t f ro m th e l a y ou t , a n y l ea k age i n th e t a n k w ou l d cause th e s pi l l t o accumu l a t e on th e d r i p t ray b e l ow th e t a nk . The d r i p p an a n d the e q ua t or i al re g i on of th e t a n k are e q u ipp ed wit h te m p e ra tu r e s e ns o r s to d e t ect th e p rese n ce of LN G. T hi s ac t s as a p art i al seco nd ary b arrier f o r th e t a nk. LN G i s usua ll y ca rr i ed i n thi s typ e of t a nk s. A f lex i bl e f ou n d a t i o n a ll o w s f re e ex p a n s i on a n d co nt ra c ti on accor din g t o th ermal co nditi o n s, a n d such di me n s i o n al c h a n ges d o n ot int e r act wit h th e p r i ma r y h u l l s t r uc t u r e. 352 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

253. T y p e ‘ B ’ tan k s T he f ollow ing are t he a dv an t a ge s o f K v a e rn e r -Mo ss Sph e r i c al t an k s: I t e n a b l es spa c e betwee n t he i nn e r and oute r h ul l whi ch can b e used f or b a ll ast a n d p r ov id ed p ro t ec ti on t o cargo i n case of s id e -w ard co ll i s i on d amages. T h e s ph er i cal s h a p e a ll o w s eve n d i s t r i b u t i o n of s t r e s s , th eref or e re d uc in g th e r i sk of f ra c t u r e or f a i l u r e. Sin ce ‘ Le ak be f o re Fa i lu r e ’ co n ce p t i s used i n th e d es i g n , i t p res u mes a n d e n su re s th at th e p r i mary b arrier (t a n k s h e ll ) wi l l f a i l p ro g ress i v el y a n d n ot ca t as t ro phi ca ll y . T hi s a ll o w s c ra ck ge n era ti o n t o occur b e f or e i t p ro p aga t es a n d causes u l ti ma t e f a i l u r e 353 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

254. T y p e ‘ C’ tan k s T h e se t a nk s a r e d e s igne d as c r y o g eni c p r e ss u r e v e ss e l s, u s in g c o n v en t i o n al p r e ss u r e v e ss e l c o d e s, a n d t h e d o min a n t d e s ig n c r i t e r i a i s t h e v apo ur p r e ss u r e . T h e d e s ig n p r e ss u r e f or t h e se t a nk s i s i n r a n ge s a b o v e 200 mb ar . T h e m ost c o mm on s h ap e s f or t h e se t a nk s a r e c y l i n dr ic a l a n d b i - l o b e . T h o ug h T ype ‘ C ’ t a nk s a r e u s e d i n bo t h , L P G a n d LN G c arr ie rs, i t i s t h e d o min a n t d e s ig n in L NG c a rrier s. N o t e , i n F igu r e , t h at t h e spa c e b e t w ee n t h e t w o c y l in d e rs i s r en d e r e d u s e l e ss. D ue t o t h i s, t h e u se of c y l in d r i c al t a nk s i s a poo r use o f the hu l l v o lu m e . I n o r d e r t o ci r cu m v en t t h i s, t h e p r e ss u r e v e ss e l s a r e m a d e t o in t e rs ec t , or bi l obe t a nk s a r e u s e d . T h e h o l d spa c e i s f i ll e d w i t h i n er t g a s o r d r y a i r . Sen sors p l a c e d i n t h e h o l d spa c e c an d e t ec t t h e c h a n g e i n c o m pos i t i o n of t h e iner t g as or d r y a i r d u e t o f u e l v apo u r , a n d l e a k a ge s c an h en c e be d e t ec t e d a n d p r e v en t e d . B i l o b e t a nk s at t h e f o r w a r d en d of t h e s h i p a r e t ap e r e d at t h e en d . 354 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

255. M emb r an e T an k s Un l ik e ind e p e nd e n t t a nk s, mem b r a n e t a nk s are n o n- s elf- s u pp o r t i n g s t r uctu r e s . T h e i r p r i mary b arrier co n s i s t s of a t h i n l a ye r of m e m b rane ( . 7 t o 1 . 5 mm thi c k) . T h e mem b ra n e i s su pp or t ed t o th e inn er h u l l s t r uc t u re th r ough an in su l a ti on th at can r a n ge up t o 10 mm thi c kn ess as p er I M O I GC Co d e. D ue t o th e i r n o n- se l f - su pp o r ti n g n a t u r e, th e inn er h u l l b ears th e l oa d s i m p arted o nt o th e t a nk . T hi s w a y , th e ex p a n s i o n s a n d co nt ra c ti o n s d ue t o th ermal f l uc t ua ti o n s are com p e n sa t ed b y n o t a llow ing t he s t r e s s t o b e t a k e n u p b y t he m e m b rane i t s el f . M em b ra n e t a nk s are p r i mar i l y used f o r LN G cargo. 355 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

256. M emb r an e T an k s The a d v a n t a g e s o f m e mb r a ne t a nks a r e a s f o ll o w s: T h e y a r e g ene r a ll y of sm a ll e r g r o ss t o nn a g e , t h at i s t h e spa c e o c cu p ie d w i t h i n t h e h u l l i s l o w e r f or a gi v en c a r g o v o l ume. D u e t o t h e ab ov e r e aso n , m a ximu m spa c e i n t h e h o l d c an be u s e d f or c a r g o c o n t a in m en t . S in c e t h e h eig h t of t a nk s a b ov e t h e m a i n d e c k is s igni f i c a n t l y l e ss e r c o m pa r e d t o t h e c as e s of M oss t a nk s, mem b r a n e t a nk s p r o v i d e a ll o w v i s i b i l i t y f r om t h e n av i g at i o n al b r i d g e . T h i s a l so a ll ow s a l o w e r w h e e l h o us e . 356 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

257. A t ypi c al L NG c a rr i e r h as f o u r to s i x ta n k s lo c at e d al o n g t h e c e n t e r -li n e o f t h e v e ss e l . In s id e e a c h ta n k t he r e a r e t y p i c ally t h r ee s u b m e r g ed pump s . T he r e a r e t w o m a i n c a r g o pumps w h i c h a r e u s ed i n c a r g o di s c h a r g e op e r at i o n s a n d a mu c h sma l l e r p u mp w h i c h is r e f e r r e d to as t he s p r a y pump. T h e spr ay pump is us e d fo r e i t he r pump in g o ut l i qu id L NG to b e u s e d as f u e l (via a v a po ri z e r ) , o r fo r c oo lin g d o w n c a r g o ta n k s . I t c a n al s o b e us e d fo r "s t ri pp ing " o u t t h e la s t o f t h e c a r g o i n di s c h ar g e op e r a t io ns . A ll o f t h e s e pump s a r e c o n tai n e d w i t h i n w h a t is k n o w n as t he pump t o w e r w h i c h h a ng s f rom t he t o p o f t he ta n k a n d run s t he e n t i r e de p t h o f t he ta n k . T h e pump t o w e r al s o c o n tai n s t h e ta nk g a ug i n g sy s t e m a n d t h e ta n k f illin g lin e , all o f w h i c h a r e l o c at e d ne a r t he bo t t om o f t he ta n k. C a r go S y s t ems M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

258. D ee p w el l p ump F o r l i q u i f i e d g as c ar g o s y s te m , d ee pw e l l p um p s are o r su b merged elect r i c a ll y b ecause of th e cargo l ow t em p era t u re. The lo ng sha f t of th e d ee pw e l l pu m p r u n s i n C ar bo n be ar i n g s , th e s h a ft b e in g p ro t ec t ed i n w ay of th e b ear in gs b y s t a i n le ss s tee l s leeve s . The pu m p sha f t i s p os iti o n ed withi n th e di sc h a r ge pip e t o a ll ow th e l iq u i d ca r go t o lub r i c a t e and coo l th e b ear in gs. The r i sk of ove rh e a te d be ar i n g s i f th e pu m p r un d r y i s r e du ced b y a p ress u r e cut - out o r th ermal s wit c h . T h e l iq u ifi ed gas i s carried at it s b o i l in g t em p era t u r e t o e n su r e th at th e u ll age s p ace a b ove th e l iq u i d i s fi ll ed wit h c ar g o v ap ou r a n d a i r i s exc l ude d. 358 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

259. D ee p w el l p ump T he r e s i d u e c ar g o t o ma int a i n th e t a n k a i r f r ee a n d a ll o w s th e t a nk t em p era t u r e t o b e k e p t at th e carr yin g l evel a n d avo i d t a n k s t r uc t u re f ro m b e in g ex p a nd ed a n d co nt ra c t e d . T h e w e i g h t of th e p ump s h a f t a n d i m p e ll er are o pp osed b y o n e o r mo r e c arri e r be arin g s. L if t f orce of th e s h a f t a l so re q u i re s a d o wnw ar d - ac tin g t hr u st be ar i n g . T he n u m be r o f pump s t a ge s i s di c t a t ed b y th e di sc h arge h ead r e qui r e d. T he i n duce r f r e qu e nt l y fitt ed t o ce nt r ifu gal l iquifi ed gas pu m p s at the pu m p suc ti o n . D ee pw e l l p um p s i n ge n eral are d r i ven b y h yd ra ul i c m oto rs o r b y a f l am e pr oo f elect r i c m oto rs s it ua t ed at d eck l eve l . D upl i c a t i o n of p um p s i n t a nk s i s th e sa f eguard aga in st b rea k d o w n of d ee pw e l l p um p s i n l iq u i d gas carriers. 359 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

260. V AC - St r i p S y s te m 360 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

261. C hemica l T an k e r C a r g o S ys tem T h e p r a ctic e o f p o siti o n i n g s u bme r si b l e o r deepw e l l p u mps w ith in ca r g o tank s e li m inat e s p u m p roo m d an g e r s . T h e e x pe n s e o f e x t r a s u cti o n p i pew o r k and t h e r is k o f m ix i n g ca r g o e s w ith r e s u lti n g c o nta m ina ti o n T h r ee c o n ce n t r ic t u b es m ake u p: t h e h i g h p r e ss ur e o i l s u pp l y p i p e to t h e h y d r a u l ic m o t o r , t he r e t ur n p i p e ( 1 , 2 ) , and a p ro t e cti v e ou t e r c o ff e r d am ( 3) . W or k i n g p r e ss ur e f o r t h e h y d r a u l ic ci r c u it i s u p to a b ou t 170 b a r and r e t ur n p r e ss ur e a b ou t 3 b a r . T h e im pe ll e r s u cti o n is p o siti o n e d cl o s e to t h e b o tt o m o f t h e s u cti o n w e l l f o r g oo d tank d r aina g e b u t w he n p u mp in g is c o mp l e t e d t h e v e r tica l d is c h a r g e p i p e will b e l e f t f u l l o f li q u i d . S t o pp in g t h e p u m p w ou l d a ll o w t h e li q u id to f a l l b ack in to t h e tank and clea r in g o f t h e tank o f ca r g o o r o f wat e r u s e d in tank cleanin g w ou l d b e a c o n s tan t p ro b l em . 361 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

262. F R AM O S ys tem 362 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

263. FRAMO - CARGO PUMPING SYSTEM Framo hydraulically driven submerged cargo pumps provide safe, efficient and flexible cargo handling of any type of liquid cargo. Improved cargo handling performance gives quicker turnaround time, more ton-miles and fewer voyages in ballast. The Framo cargo pump is of a robust construction made to efficiently empty any cargo tank containing the most heavy, viscous or aggressive cargoes. The hydraulic driveline is designed for a safe and reliable pumping and final stripping of the most volatile or dangerous cargoes carried in bulk. No risks of any build up of heat due to a fail-safe design where the pump motor and bearings are constantly lubricated and cooled by the hydraulic oil driving medium. The Framo cargo pump can handle any type of cargo. One voyage it may be a petroleum product, next voyage an acid or something heated/cooled/volatile or viscous. A cargo pumping system must be able to discharge, drain and clean the cargo tanks in an efficient manner to make the vessel ready to receive a new cargo. The Framo cargo pump is a vertical single stage centrifugal pump powered by a hydraulic motor for safe and efficient operation. All our cargo pumps are made in stainless steel material and designed with a smooth and easy-to-clean surface with a limited number of flanges which gives a superior ability to pump any liquid. Vertical single stage, single suction impeller, axially balanced Robust hydraulic drive with short and stiff drive shaft. Cofferdam, ventilated to atmosphere, protecting the entire pump. Anti-rotation brake; loading through pump

264. The pump’s cofferdam is purged before and after discharge operation. Any leakage across the cargo seals or hydraulic oil seals collected in the cofferdam, will be forced to the exhaust trap on deck where it can be measured. This is a simple and reliable seal condition monitoring system. No need for any electric sensors nor any automatic control system.

265. When the cargo tank is empty, the speed of the cargo pump is reduced to perform the final stripping of tank: • Close the cargo valve • Open the small ball valve on the stripping line • Pressurize the pipe stack by connecting the purging hose with compressed air or nitrogen press cargo out through the stripping line and into the cargo line The pump impeller rotates and acts as a non-return valve to prevent cargo from returning back to tank. the Framo cargo pump can be equipped with a vacuum drain line that will empty suction well completely and allow for a dry tank top and quick re-loading of cargo. Stripping

266. FRAMO – DESIGN FEATURES Concentric hydraulic pipes for maximum safety. Mechanical seal against hydraulic oiL Double lip seal against cargo, only exposed to static pressure. Smooth pump exterior; self draining and easy to clean. The Framo cargo pump is easy to operate. The hydraulic drive provides for a remote and local stepless capacity control through the Speed Torque Control (STC) valve on the pump’s top plate. The cargo pump can pump anything liquid, regardless of specific weight or viscosity. It is impossible to overload or to overspeed the pump. The STC valve automatically regulates hydraulic oil pressure and flow to the hydraulic motor according to the given discharge situation. The pump design allows operation with a minimum of liquid in the tank which saves time spent for drainage and tank cleaning. The Framo cargo pump has a built-in efficient stripping system. Seal monitoring is performed from the cargo pump top plate by purging the cofferdam. Replacement of wear and tear parts is easily done from inside of the tank without interfering with the hydraulic section. Dangerous chemicals, acids, oils or edibles must be handled in a safe way for people and environment. The tanker must be equipped with cargo pumps that can efficiently empty cargo tanks and associated cargo piping to meet the most stringent requirements, and withstand the tough impact during hours of tank cleaning afterwards. Switch between cargoes without cargo contamination. Carry anything from acids to drinking water.

267. F R AM O S ys tem p u r g in g c o nn e c t io n s a re f i tte d t o c l e ar th e d i s c h a r g e p i p e ( a n d t h e c of f e r d a m if the re is le a k ag e ) . D isc h a r ge p i p e p u r gi n g is e f f e c t e d b y c l o si n g t h e de ck d i s c h a r ge va l v e a s t h e t a n k c l e a r s o f l i q u i d , t h e n w i t h t h e pu mp l e ft r unn i n g t o p r e v e n t c a r go f a llb a ck o pe n i n g t h e pu r ge c o nn e c t ion s h o w n . T h e co m p r e s s e d a i r o r i n e rt g a s at 7 b ar w i l l c l e ar th e v e r t i cal d i sc h a r ge p i p e b y p r e s s u r i si n g it f r om th e t op a n d f o r ci n g l i qu id cargo u p th ro u gh th e sma l l ris e r t o th e de ck mai n . T he c o ffe r d am is a l so p r e s s u r i s e d be fo r e t h e p u mp is s t o p p e d , t o c h e ck for le a k a ge . T h i s s a f e t y c o ff e r d am a r o u n d t h e hy d r a u l ic p i pe s is c o nn e c t e d t o t h e d ra i n a ge c h a m b e r a t t h e b o t t o m o f th e p u m p . Se a l s a b o v e a n d b el ow t he c h am b e r e x c l ud e i n g r e ss o f l ow p r e s s u r e hyd r a ul i c o il a n d l i q u id c a r g o f r o m the t a nk , re s p e c t iv el y . T h e b o t t om s e al i s s ubj e ct o nl y t o p r e s s u r e fr o m t h e h e a d of cargo in th e t a nk , n ot t o pu mp pre s s u re . 363 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

268. F R AM O S ys tem D E S I GN P RE SS U RE: C A RG O 25 B A R HI G H P R E SS U R E, H Y D R AU L IC : 320 B A R R E T U R N P R ESS U R E , H Y D R AU L I C: 16 B A R C O FFE R D A M: 10 B A R S ub m er g ed B a ll a s t W a ter Pu m p 364 M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G 18 S ep tem b er 2020

269. 6 . Cargo Systems Submerged Cargo Pump System (Frank Mohn) The practic e o f positioning submersible o r deepwel l pump s within carg o tanks eliminate s pum p room dangers. The expens e o f extra suction pipewor k an d the risk o f mixing cargoes with resulting contamination Three concent ric tubes make up: the hig h pressur e oi l supply pip e (1) to the hydrauli c motor, the return pip e (2 ) , an d a protective oute r cofferda m (3) . Working pressur e for the hydrauli c circui t is u p to abou t 17 ba r and return pressur e abou t 3 ba r . The impeller suction is positione d clos e to the botto m o f the suction well for goo d tank drainag e bu t when pumpin g is complete d the vertica l discharg e pip e will b e left full o f liquid. Stopping the pum p would allow the liquid to fall bac k into the tank an d clearin g o f the tank o f carg o o r o f water use d in tank cleaning would b e a constan t problem. T ues day, Febr ua ry 10 , 2015 325

270. Submerged Cargo Pump System (Frank Mohn) purgin g connection s ar e fitted to clea r the discharg e pip e (and the cofferda m if there is leakage) . Discharge pipe purging is effecte d b y closing the dec k discharge valv e a s the tank clear s o f liquid, then with the pum p left running to preven t carg o fallback openin g the purg e connect ion shown . The compresse d ai r o r inert ga s a t 7 ba r will clea r the vertica l discharge pip e b y pressurising it from the top an d forcing liquid carg o up through the small riser to the dec k mai n . The cofferda m is also pressurise d befor e the pum p is stopped, to chec k for leakage . This safety cofferda m aroun d the hydrauli c pipes is connecte d to the drainag e chambe r a t the botto m o f the pump. Seals abov e an d below the chambe r exclud e ingress o f low pressure hydrauli c oi l an d liquid carg o from the tank, respectively . The botto m seal is subje ct onl y to pressur e from the hea d o f carg o in the tank, no t to pum p pressur e . 6 . Cargo Systems T ues day, Febr ua ry 10 , 2015 326

271. Submerged Cargo Pump System (Frank Mohn ) T ues day, Febr ua ry 10 , 2015 327 DESIG N PRESSURE: CARGO 2 5 BAR HIG H PRESS U RE, HYDRAULI C : 32 BAR RETURN PRESSU R E , HYDRAULIC : 1 6 BAR COFFERDAM: 1 BAR

272. Subm e rged Ballas t W a ter Pump T ues day, Febr ua ry 10 , 2015 328

273. SUBMERGED BALLAST PUMPS Installation of ballast pumps inside the double side ballast tanks in combination with a submerged cargo pump in each cargo tank make the pump room superfluous. This arrangement provides a safer ship design and make more space available for carrying cargo. The Framo submerged ballast pump is a centrifugal pump, designed for installation inside the ballast tanks. The pump unit is mounted inside the air separator and protected by a cofferdam. A fail-safe design ensures that impeller will always be immersed in water. This is a compact design which saves space and makes the installation easy. An air ejector is connected to the pumps suction side. Automatic start and stop of the air ejector makes the pump self priming. The pump is manufactured from stainless steel with seawater resistant bronze impeller. Individual capacities of up to 3.000 m3/h. Stepless capacity control Robust design with a short and rigid drive shaft Lubrication and cooling of motor and bearings by the hydraulic drive oil Cofferdam between ballast water and hydraulic section Concentric hydraulic pipes for maximum safety Easy to install, operate and maintain Can be connected to any ballast water treatment system.

274. 2015 Complete System T ues day, Febr ua ry 10, 330

275. HYDRAULIC DRIVE

276. HYDRAULIC DRIVE A complete system designed and assembly manufactured by Framo . Hydraulic drive provides the most flexible and safe power transmission for a cargo pumping system on tankers. The hydraulic power pack prime movers can be electric motors or diesel engines. A combination of electric motor and diesel engine prime movers allows the ship’s generators to be designed for the relatively low power requirement in sea-going mode rather than the considerably higher requirement during cargo unloading. The ship’s auxiliary engines can therefore operate with an economic load while at sea where the majority of running hours will be. The diesel hydraulic power packs will provide any additional power needed for a high capacity/high head cargo discharge. All power packs, stainless steel system tank, oil cooler, and full flow filter are mounted, piped and wired on a module for resilient installation onboard. This Hydraulic power unit is full scale tested together with the control system module before shipment. The hydraulic pumps are of the variable displacement type and fitted with a pulsation damper for maximum reductions in pulses and noise. A power saving device incorporated into the Framo control system automatically regulate and share the load between each power pack in operation. The hydraulic power unit and all cargo pumps and other consumers are operated and monitored from the Framo control panel. The control system can be interfaced with ships Integrated Control System.

277. FRAMO PIPING

278. FRAMO PIPING The need for quality hydraulic installation onboard vessels operating in severe marine environment has led to the development and manufacturing of Framo hydraulic piping systems. The hydraulic piping system is based on high quality components and piping materials. Duplex stainless steel on all high pressure branch pipes and pilot pipes on deck. Stainless steel AISI 316L on all low pressure hydraulic pipes on deck. The hydraulic pipes are of high standard with smooth internal surface intended for hydraulic oil with high cleanliness. All service valves are made from stainless steel. The Framo hydraulic piping system is designed with extensive use of cold bending in order to limit the number of flanged connections. Framo supply specially designed flanges for all pressure ratings, flexible bulkhead penetrations, resilient pipe clamps, anchor supports, and other accessories for the hydraulic piping system. Prefabrication of the piping system to any level of complexity from a single spool piece to a full system is available. In all areas of design special attention is given to reduce vibration and noise from components and pumps. The cargo pumps, hydraulic power units and hydraulic piping are all resilient installed. The cargo piping arrangement depends on the type of vessel, the cargoes carried and the number of segregations required. In close cooperation with shipowner and yard Framo can assist in designing an optimal cargo piping layout. A functional system should not only be designed with the purpose of a quick loading and discharge operation, but also provide for efficient draining and cleaning. To prevent sediments settling on the tank-top during transport and to maintain the liquid quality, a Framo diffusor can be installed on the outlet of the dropline. During voyage cargo is circulated through the diffusor by running the cargo pump at intervals. The diffusors are specially designed for individual cargo tanks, and each diffusor contains several nozzles, whose number and dimensions are determined on the basis of the dimensions and shape of the tank-top. Diffusors are normally produced in high-molybdenum stainless steel for exposure to Phosphoric Acid, but are also available in AlSl 316L for other cargoes. Forced cargo circulation should be repeated at regular intervals throughout the voyage

279. CARGO HEATING Framo deck mounted cargo heaters eliminate the need for in-tank heating coils. The cargo tank interior can be made with flush tank top free from coils, brackets and clamps. A flush tank top facilitates quicker stripping with less cargo remaining in the tank. The cargo tank washing can be performed quicker, with less consumption of washing water and less slop handling. High flexibility to heat all traded cargoes, such as heavy fuel oils, oil products, palm oils and other chemicals that may be temperature sensitive and requires a gentle heating procedure. The specially shaped heating elements secure easy cargo circulation and have a low surface temperature against cargo. The high capacity and low pressure drop through the cargo heater gives a low power consumption during circulation and secure a good mixing and heat distribution inside the cargo tank. The heating medium can be saturated steam, hot water or thermal oil. Framo deck mounted cargo heating system is supplied as an integral part of the cargo pumping system for all sizes of oil tankers, chemical tankers. Circulate the cargo through the deck mounted cargo heater Adjust heating capacity to meet cargo requirements Heat gently with careful temperature increase across the heater High circulated cargo flow gives a good heat distribution inside the cargo tank. The cargo heater is made for a tough marine environment Stainless steel Compact welded plate type design • Large heating surface • Low pressure drop • Vertical self draining • Easy to clean • Easy to inspect • Cargo heater is only exposed to cargo when in use

280. PRESSURE SURG E A N D LIQUID P R ESSURE T ues day, Febr ua ry 10 , 2015 339 When a valv e o n a liquid line is close d too quickl y , the pressur e inside the line increases to a hazardou s hig h level ver y quickly. Quick change s to the liquid flow in a pipeline may lead to a pressur e surge resulting in a rupture in the pipeline system. This surge pressur e ca n b e recognised b y a “knock” in the pipeline . This type o f pressur e pea k is generate d ver y quickl y in the pipeline , faster than a common safety valve is capable to relieve . The consequ e n c e may b e the breakdow n o f the pipeline system an d thereby hig h risk of pollution , fire an d persona l injury . Pressure surge may appear if: The emergency shutdo w n valves are activated and closed too quickly. ESD/Emergency Shut Down) Fast closing/opening of manual or remote operated valves. Fast variation of the volume flow resulting that a no n - r etu rn valv e starts hammering. When a pump is started and stopped.

281. PRESSURE SURG E A N D LIQUID P R ESSURE T ues day, Febr ua ry 10 , 2015 340 A pipeline o f 25 meters an d 15 mm in diamete r is use d for water transfer a t a capacit y o f 400 m3/hrs. The total mass o f the moving liquid inside the pip e is 440 k g an d moves with a velocity of 6, 3 meters/ s ec on d . If a valv e is close d immediately, the kinetic energ y will conver t almost immediately to potentia l energy . The pressur e surge may reach approximatel y 4 bar s within 0,3 seconds. If the liquid is a conden s e d ga s o r crud e oil , vapou r may b e present . These vapou r bubble s will collaps e when the pressur e increases. The collapse d bubble s will generat e pressure waves that will also b e transmitt e d through the pipeline system. In a n opposit e cas e where the pressur e is decreasin g rapidly, a volatile liquid will start boiling . The abov e mentioned case s illustrate why it is especially important that the valve s an d pump s ar e cautiously operate d so neithe r dangerous pressur e peak s no r pressur e drop s ar e generated.

282. PRESSURE SURG E A N D LIQUID P R ESSURE T ues day, Febr ua ry 10 , 2015 341

283. PRESSURE SURG E A N D LIQUID P R ESSURE A pressur e pea k is generate d an d will b e transmitted a t the speed o f sound (the onl y way possible) bac k towards the pump . When the wave o f pressur e reaches the pump , some o f the pressur e will unloa d through the pump , bu t the resistance her e will also operat e a s a “ wall ” . The pressur e is rebuilt an d reflected bac k towards the ESD valv e again. T ues day, Febr ua ry 10 , 2015 342

284. PRESSURE SURG E A N D LIQUID P R ESSURE T ues day, Febr ua ry 10 , 2015 343

285. PRESSURE SURG E A N D LIQUID P R ESSURE T ues day, Febr ua ry 10 , 2015 344 Maintenance an d testing o f the ESD - valves’ closing time is the most important of the above mentioned causes . Closing time o f the ESD-valve s , which is too short, may lead to generatio n of a dangerou s pressur e surge. Always consul t the terminal represen t ative s abou t the required pipe line period. Necessary time for a safe closur e o f valve s ca n b e calculate d base d o n the expecte d maximum pressur e surge when the pressur e wave ha s passe d forward an d backwar d through the pipeline. The speed o f the sound is set to 1,32 m/s. If the pipeli n e is 2 km , the calcu lated time for maximum pressur e surge a t closur e o f the ESD valv e is: T = (2 x L) / Speed o f sound = ( 2 x 2,00 m) / 132 m/s = 3 s The maximum pressur e surge will occu r 3 seconds from closur e o f the ESD valve . This time is called a “ pipeline perio d ” . It is assume d that the safe closing time is five times a pipeline period , so the closing time should a t minimum be: 5 x 3 s = 1 5 seconds

286. Life boats

287. A  lifeboat  or  life raft  is a small, rigid or inflatable  boat  carried for emergency evacuation in the event of a disaster aboard a ship.  Lifeboat drills  are required by law on larger commercial ships. Rafts ( life rafts ) are also used. In the military, a lifeboat may double as a  whaleboat ,  dinghy , or  gig . The  ship's tenders  of  cruise ships  often double as lifeboats. Recreational sailors usually carry inflatable life rafts, though a few prefer small proactive lifeboats that are harder to sink and can be sailed to safety. Inflatable lifeboats may be equipped with auto-inflation ( carbon dioxide  or  nitrogen ) canisters or mechanical pumps. A quick release and pressure release mechanism is fitted on ships so that the canister or pump automatically inflates the lifeboat, and the lifeboat breaks free of the sinking vessel. Commercial aircraft are also required to carry auto-inflating life rafts in case of an emergency  water landing ;  offshore oil platforms  also have life rafts.

288. Lift boat davit is usually referred to "davit". It is designed for unlading lifeboat or work boat of special equipment. According to the launching modes of operation, it can be divided into roll out type, wave inverse and gravity type. With the requirements of SOLAS (Convention on the Safety of Life at Sea) norms, now lift boat davit is divided into drop type, gravity fall arm type, four connecting rod type, platform, single arm cranes, etc. This davit is used to store, land and recycle lifeboat special combination frame. Located on both sides of the ship deck, lift boat davit is usually inside the ship's rail. When it is used, the davit extends out, lifts the boat and puts it down. The design of the lift boat davit is in accordance with the latest requirements of the standard 1974 SOLAS and international LSA Code (MSC 48(66)) Lift Boat Davit

289. DAVITS

290. Deck fitting is a type of ventilated attachment that must be screwed tightly to the deck of the vessel for sturdy transport. For boaters, deck fitting is referred to pieces of hardware. These metal pieces are used to secure various items to the deck, including fishing rods, ropes and rigging, tarps and sails, railings, life preservers and steering wheels. These deck fittings come in many shapes and sizes. Eg:custom -made roller chocks, roller fairleads, towing pads, chain stoppers, etc. Deck Fitting

291. A fairlead is a device to guide a line, rope or cable around an object, out of the way or to stop it from moving laterally. Typically a fairlead will be a ring or hook. The fairlead may be a separate piece of hardware, or it could be a hole in the structure. A fairlead can also be used to stop a straight run of line from vibrating or rubbing on another surface. An additional use on boats is to keep a loose end of line from sliding around the deck FAIR LEAD

292. A capstan is a vertical- axled rotating machine developed for use on sailing ships to apply force to ropes, cables, and hawsers. The principle is similar to that of the windlass, which has a horizontal axle. CAPSTAN

293. Capstan

294. Ship capstan  is the device installed and used on ships to wind rope, cable or chain during anchoring, mooring, pulling, loading, unloading operations and so on. From the ship capstan definition we can know that the capstan has wide application, which makes it important equipment on ship. The capstan is a drum shaped machine and it includes horizontal capstan and vertical capstan, one advantage of using capstan on ship is that it can save some weight and space on deck especially as vertical capstan because its motor and some other parts are mounted below deck. The capstan is the simple but important device on ship no matter what drive type and what installation way it adopts, and it makes ship anchoring and mooring easier because it has easy operation and can work efficiently like marine winches for boats. If you have any question about ship capstan for sale, just tell us and we will provide solutions for you very soon. Choose the capstan for your ship from our company, and you will get quality product with reasonable price.

295. . Before Operation 1) Take down the canvas cover on the deck machinery, then check whether there are some obstacles around and the control crank is in neutral position or not. This can prevent oil motor from suddenly moving when hydraulic pump is started. 2) Check and confirm that the hydraulic tank’s oil level is normal. 3) Forbid the use of shore power control hydraulic ship deck machinery. 4) After the first start or maintenance, we should check whether the steering pump is consistent with the arrow direction on the pump case. Don’t keep the hydraulic pump reversal to avoid damaging the hydraulic pump. Check whether pipeline has leakage and there is abnormal sound and vibration or not during pump’ running. 5) Confirm all the above normal, and then release the dog driver from the reversing handle of deck machinery. OPERATION CAUTIONS OF DECK MACHINERY

296. During Operation 1) When operating in the navigation bridge (if already long-time no use), spin the bypass valve on the remote console to the bottom towards the operation direction, and then connect the reversing valve rod of the ship deck machinery with the actuating mechanism of remote control oil cylinder. 2) When operating the warping winch, push the control handle to the warping position. While heaving up the anchor, loosen the chain cable stopper and hand brake band, and then push the clutch handle to the heave away anchor position. 3) Pay attention to the pressure gauge of the remote control box during running. If the pressure exceeds the rated pressure, we must stop operation. 4) When the remote control handle is in the neutral position, cable crane hydraulic brake cylinder should be in brake position. If the red light of the remote control station is on, it means that the brake system works well. .

297. . After Operation 1) Brake the anchor machine brake tightly, close the chain stopper, open the clutch, put the control handle in neutral position, release the actuating mechanism of remote control oil cylinder, and then use the dog driver to lock the handle. 2) Put the remote control handle of the navigation bridge in the neutral position, spin the bypass valve to the bottom towards the BYPASS direction, and then close the pump power. 3) Use canvas cover to cover the deck machinery. .