DamageControlProcedures easy to understand

procedures for Damage contr

1. Antwerpen - 2004 Jan D'Haeyer 1 IMO Res.A891(21) Stability & Ballast Control - Offshore Installations Pt.11: Damage Control Procedures

2. Antwerpen - 2004 Jan D'Haeyer Slide 2 Pt.11: Damage Control Subject : damages affecting watertight integrity Semis may lose stability and watertight integrity due to: collision damage heavy weather structural damage main structure failure failure of ballast control system sub-surface blowouts (drilling vessels) Jack-ups whilst afloat are most liable to lose stability and watertight integrity due to: collision damage heavy weather structural failure

3. Antwerpen - 2004 Jan D'Haeyer Slide 3 Pt.11: Damage Control Between 1979 and 1989 seven offshore units worldwide suffered accidents which resulted in the death of 660 people. Five of those incidents resulted in the total loss of the unit. Some of these names we know well: Ocean Ranger (ballast control failure) Piper Alpha (fire/explosion) Alexander L. Kielland (structural failure) Others, which operated in other parts of the world, are less well known to us but the tragedies were of equal proportion: Bohai 2 Glomar Java Sea Enchova PCE, 1 Seacrest IXTOC 1 (blow out in the GoM – huge oil pollution) Between 1970 and 1995 162 rigs were total losses. Since then we have known the Petrobras P36 foundering, and ??

4. Antwerpen - 2004 Jan D'Haeyer Slide 4 Accident experience - cases Alexander L. Kielland platform Pentagon type semi-submersible mobile rig developed in France Constructed 1973-1976 as a drilling rig 5 columns designed as buoy – each column 35,6m high mounted on 22 m diamter pontoons, columns placed in the vertices of the pentagon shape Platform could accomodate 212 people Alexander L. Kielland accident Date: 27 March 1980 Location: Ecofisk field – Northsea Conditions: poor weather – 60-75 km/h wind velocity – 6-8m wave height Failure: fatigue fracture followed by a brittle failure in one of the braces and a ductile overloading of the adjacent braces Cause: fatigue crack initiated by a welding error at a hydrophone Duration: the platform capsizes 30-35 degrees and 20 minutes after column D is lost the platform sinks Consequence: loss of 123 lives and a platform (89 survived)

5. Antwerpen - 2004 Jan D'Haeyer Slide 5 Accident experience - cases Wreck of the Alexander L. Kielland

6. Antwerpen - 2004 Jan D'Haeyer Slide 6 Ocean Ranger platform Built at Mitsubishi Heavy Industries, Japan, 1976 Massive semisubmersible drilling rig able to drill in dangerous areas, biggest rig of her days Operated in the Bering Sea off Alaska(’76) – New Jersey – Ireland – Grand Banks (’80) Ocean Ranger Accident Date: February 15th 1982 Location: Grand Banks of Newfoundland, 170 miles of St.-Johns Circumstances: vicious storm – winds up to 90 knots – seas over 30 m high – sea water temperature -1,2 degrees Cause: (1) crew reported a giant wave smashing a port hole in the ballast control room – short circuit and rig began to list – overballasting to one side and capsized (2) training of crew was insufficient at best (3) engineering and design and construction faults – ref. p417 (4) inadequate safety equipment Consequence: killing 84 people (full crew, no survivors)

7. Antwerpen - 2004 Jan D'Haeyer Slide 7 Ocean Ranger

8. Antwerpen - 2004 Jan D'Haeyer Slide 8 Piper Alpha Date: July 6, 1988 Location: North Sea An initial leak at 10:00 PM ignited and led to a series of fires and explosions which destroyed the platform Cause1: The initial leak was caused by starting up the backup condensate pump which was under maintenance (valve was removed). The control room was not informed that maintenance was not completed yet. Cause2: The automatic deluge system was not activated since it was turned off !! It is estimated that the rate of energy released during the incident was equal to 1/5th of the UK energy consumption ! At the fire's peak, the flames reached 300 to 400 ft in the air and could be felt from over a mile away and seen from eighty-five ! Consequence: Killed 167 men and platform lost (worst offshore accident ever)

9. Antwerpen - 2004 Jan D'Haeyer Slide 9 Piper Alpha before and after July 6th, 1982

10. Antwerpen - 2004 Jan D'Haeyer Slide 10

11. Antwerpen - 2004 Jan D'Haeyer Slide 11

12. Antwerpen - 2004 Jan D'Haeyer Slide 12 Accident experience - cases Piper Alfa – fire/explosion

13. Antwerpen - 2004 Jan D'Haeyer Slide 13 Glomar Java Sea Global Marine Drillship 5930 ton Foundered at South-Vietnam 25 October 1983 Cause: unexplained crack in hull + typhoon Lex + poor emergency response local authorities All crew lost (81 pers)

14. Antwerpen - 2004 Jan D'Haeyer Slide 14 Ixtoc 1 – blow out – huge oil spill in GoM

15. Antwerpen - 2004 Jan D'Haeyer Slide 15 Petrobras P36 Friede & Goldman L-1020 Trendsetter design semisubmersible Date: March 15th 2001 Location: Campos Bassin, Brazil Conditions: good weather Cause: 1– rupture of drain storage tank being eronuously filled by hydrocarbons, destroying adjacent piping, a.o. fire line 2 – explosion of gaz, hitting 10 firemen (fatal) 3 – serial filling of void spaces Consequence: 10 firemen (others safely abondoned)

16. Antwerpen - 2004 Jan D'Haeyer Slide 16

17. Antwerpen - 2004 Jan D'Haeyer Slide 17 Pt.11: Damage flooding Loss of stability and/or watertight integrity generally occurs because FLOODING takes place in compartments which were previously empty and watertight Damage flooding above waterline is not immediately threatening but may become so below waterline will cause: loss of buoyancy heel or trim combined heel and trim at the waterline will cause decrease of GM: added weight affects KG, draft increase/ reduction of freeboard loss of waterplane area add to that free surface effect free communication effect trim/list

18. Antwerpen - 2004 Jan D'Haeyer Slide 18 Pt.11: Damage Control General principles of damage flooding control : action should be taken based on: 1) ISOLATION 2) INVESTIGATION 3) REMEDIAL ACTION

19. Antwerpen - 2004 Jan D'Haeyer Slide 19 Pt.11: General principles of damage control 1) ISOLATION in damage flooding this means: confining the flooding to those compartments which are damaged only closing off the vent trunks, hatches, doors and pipeline systems serving that space closing adjacent compartments and all their openings to prevent progressive flooding closing down openings on the main and below deck spaces which connect to the damaged area positively CONFIRMING that isolation is effective

20. Antwerpen - 2004 Jan D'Haeyer Slide 20 Pt.11: General principles of damage control 2) INVESTIGATION a proper investigation entails: examination of the boundaries of the flooded area and confirmation of isolation assessment of the consequences of damage in terms of stability, likelihood of further progressive flooding or weakening of the boundaries of the damaged area examination and monitoring of adjacent spaces to discover if they are still watertight assessment of the remaining capability to deal with situation in terms of power, pumping capability, counter-flooding space, etc. assessment how critical the situation is in terms of survivability of the vessel (abandon?)

21. Antwerpen - 2004 Jan D'Haeyer Slide 21 Pt.11: General principles of damage control 2) INVESTIGATION (continued) in damage flooding this means: assessment of the physical and mental fitness of the crew to take measures to save their vessel and themselves. Panic, loss of self control are human reactions to perceived life-threatening situations rapid deterioration in crew effectiveness responses often uncoordinated due to fear strong leadership, clear instructions and decisive effective orders might overcome this good training is required for having correct reflexes

22. Antwerpen - 2004 Jan D'Haeyer Slide 22 Pt.11: General principles of damage control 3) REMEDIAL ACTION effective remedial action cannot be taken unless the implications of the ISOLATION and INVESTIGATION procedures have been assessed assessment may take a very short time aim of remedial action: 1) prevent further loss of GM 2) stabilise, then rectify excessive trim/list 3) prevent progressive flooding 4) preserve the viability of life saving systems

23. Antwerpen - 2004 Jan D'Haeyer Slide 23 Pt.11: General principles of damage control 3) REMEDIAL ACTION (continued) most semi-submersibles, if operated within their stability limits, can sustain considerable flooding damage before foundering is inevitable unless catastrophic failure of structure occurs, immediate capsize or rapid sinking is unusual well documented cases show that time periods after damage when correct assessment and remedial actions have been taken would have prevented the loss example Ocean Ranger versus Ocean Nomad most semi-submersibles possess sufficient tankage and pumping/flooding capacity to reduce trim/list, mostly sufficient to recover the vessel at least in attitude where progressive downflooding danger would be greatly reduced

24. Antwerpen - 2004 Jan D'Haeyer Slide 24 Pt.11: Damage Control Plan Majority of semis can prepare damage control/counter ballasting and action plans for the types of flooding they are likely to suffer Damage Stability Booklet (as approved) contains necessary information which can be translated into practical contingency plans CAUTION : damage stability conditions, although accounting for 50kn wind heeling, do NOT take account for: ship motion in seaway prevailing weather and sea conditions mooring line restraint

25. Antwerpen - 2004 Jan D'Haeyer Slide 25 Pt.11: Damage Control Plan Flooding damage control plan should contain: detailed tank plans with details of location, volume, layout, normal content, ... location of openings to compartments air pipe, sounding pipe, hatches, accesses, … pipeline drawings filling and discharge lines, details of crossovers to other systems working limits power generation for pumping capacity, valve control and indication details of stand-by control and power Damage Stability worked examples with applicable plans and diagrams - diag 160 p.571

26. Antwerpen - 2004 Jan D'Haeyer Slide 26 Pt.11: Types of damage Four types of damage assessed: 1) flooding of tanks and voids 2) flooding of pump room and control space floods 3) fire and explosion 4) sub-sea blowout

27. Antwerpen - 2004 Jan D'Haeyer Slide 27 Pt.11: Flooding of tanks and voids Flooding of tanks and voids can occur due to: external agents collision with work boat internal causes malfunctioning of ballast control system operator error structural failure both of space boundaries or pipe work systems Transit condition: collision would result in flooding of lower hull tanks not usually threatening very large capacity exist to counteract by filling diagonally opposite tanks alternatively rapid trim/heel so to bring the damage above the waterline however, due to high GM values at that draft it requires very large amounts of ballast to apply significant heeling levers

28. Antwerpen - 2004 Jan D'Haeyer Slide 28 Pt.11: Flooding of tanks and voids At operational draft more critical if midship columns are struck, not so critical (only heel effect) if end column is struck, it can become critical it results in both heel and trim, bringing the corners (downflooding points) down close to the water level flooding damage usually occurs in those compartments furthest away from pump rooms, with a consequence of potential suction head problems also human failure often results in head down trim typical human errors: line up incorrect tanks, leave valves open in best efforts, one is often blind for the obvious and persist with ‘corrective’ actions, only making things worse remember: ISOLATE/INVESTIGATE/CORRECTIVE ACTION stop the pumps, close the valves, find out where the ballast is, decide on a practical recovery plan and commence corrective action step by step good training results in consequent automatic response

29. Antwerpen - 2004 Jan D'Haeyer Slide 29 Pt.11: Flooding of tanks and voids Vessel at operational draft: most critical point to evaluate is the actual volume likely or actually flooding diag 161 p.573: three typcial column flooding types good practice to assume the worse case (type 3) multiple compartment flooding has potentially most severe consequences e.g. due to common control system fault good practice to keep end tanks full furthest away from pump room apply mechanical isolation valves on the manifold a split manifold (forward group, aft group) flooding of brace structures usually not severe, small volumes involved dangerous if brace connection to columns are penetrated hull strength !!

30. Antwerpen - 2004 Jan D'Haeyer Slide 30 Pt.11: Flooding of pump room Pump room and control room floods mostly due to sudden failure of component carrying liquid under pressure corrosion on stub pipes i.w.o. hull skin collapse of pump casing blowout of pipe flange joints cracking of covers on sea chest strainer boxes worst case scenario: rapid and uncontrollable, volumes involved might be considerably in excess of pump capacity example 3rd paragraph page 574 problems can become very complex loss of a pump due to flooding might not be that threatening in terms of survivability, but commercial consequences are serious (vessel out of action)

31. Antwerpen - 2004 Jan D'Haeyer Slide 31 Pt.11: Fire and explosions Fire/explosion hazard from: normal shipboard fires machinery, accommodation, chemical storage, … activity related sources drilling units : mostly uncontrollable fires and explosion due surface blowout only remedy might be jettisoning of the mooring lines and pulling away from the well head also large escapes of highly toxic and explosive gas mixtures, both hydrogen sulphides and hydrocarbons usual response is abandoning the vessel floating production vessel : i.c.o. fire in production ‘train’, deluge systems (water/foam) are release usually large amounts of water are not entering the watertight boundaries intervention support ship’s fire fighting capacity can destroy

32. Antwerpen - 2004 Jan D'Haeyer Slide 32 Pt.11: Sub-sea blowout Occurs at or around the wellhead when the pressure of oil/gas deposits cannot be controlled Shallow gas blowout is particullarly dangerous as no BOP stack is installed yet Diag 162-163-164 p.576-578 gas bubbles rise from seabed, expanding due to decreasing water pressure (some small units were lost) gas areates the water, reducing it’s effective density loss of buoyancy, sinkage, list and trim gas on breaking surface may explode or ignite around the vessel only be moving away the risk can be minimised release of mooring must take place very quickly, before explosion/ignition occurs !

33. Antwerpen - 2004 Jan D'Haeyer Slide 33 Pt.11: Sub-sea blowout

34. Antwerpen - 2004 Jan D'Haeyer Slide 34 Pt.11: Sub-sea blowout

35. Antwerpen - 2004 Jan D'Haeyer Slide 35

36. Antwerpen - 2004 Jan D'Haeyer Slide 36

37. Antwerpen - 2004 Jan D'Haeyer Slide 37 Blow out

38. Antwerpen - 2004 Jan D'Haeyer Slide 38

39. Antwerpen - 2004 Jan D'Haeyer Slide 39 Blow-out

40. Antwerpen - 2004 Jan D'Haeyer Slide 40 Pt.11: Sub-sea blowout Normal practice during the time that ‘surface hole’ is being drilled is to keep very careful watch both visually and remote with sub-surface TV or ROV keep mooring release system at high state of readiness upon any indication of gas bubbles the vessel goes in alert status drilling suspended, anchor windlass and command centre manned and ready to respond if the threat is confirmed however, reluctance to disconnect and move away exists it is perceived as an admission of failure from the part of the drilling team

41. Antwerpen - 2004 Jan D'Haeyer Slide 41 Pt.11: Damage evaluation- WT integrity It is essential to obtain data on where has flooding occurred how did it occur is it still occurring how can it be isolated or stopped investigation in e.g. pump rooms readily easy due to accessibility other compartments might not be that accessible tanks and void spaces can also be pressurised due to flooding once you open the hatch, manhole cover, … it will be impossible to close again, resulting in unnecessary progressive flooding question the reason for entry, perhaps it is not necessary

42. Antwerpen - 2004 Jan D'Haeyer Slide 42 Pt.11: Damage evaluation- WT integrity void compartments can be flooded and overpressurized, how do you know? bolted manholes: slack off bolts and lift hatch little only top opening clipped hatches: drill a 10mm hole use airpipe for sounding: cut off the air vent top chain lockers cut window in spurling pipe flooding via interconnected pipelines great difficulty: how and through which valves is transfer occurring? e.g. mimic control panel indicates all valves shut, but transfer is occurring local investigation of the valves must take place if necessary actuators are to be removed to check for sheared spindles it is important that pump rooms do have necessary means for quick diagnosis readily in place (schematic diagrams, manuals, operating and repair instructions, …) and that components are properly marked (at least should local and remote ID’s be the same)

43. Antwerpen - 2004 Jan D'Haeyer Slide 43 Pt.11: Damage evaluation- WT integrity Process of evaluation of flooded volumes should be continuously monitored and updated if in doubt about flooded volume, think pessimistic make comparison between your pessimistic evaluation damage conditions contained in ship’s documentation mark up a simple line diagram on ship’s drawing condition after damage in terms of draft, list, trim, freeboard and vulnerable downflooding points some idea can be gained of likely consequences of flooding and remaining reserve buoyancy, positive GZ

44. Antwerpen - 2004 Jan D'Haeyer Slide 44 Pt.11: watertight integrity - vent heads Diag 170 p.590-592 air pipes are arranged at main deck level with tank check valves : close when the top of the air pipe is submerged (prevention of downflooding) allow in- and outflow of air (avoid under- and over pressure) during damage control, it might be desirable to shut the air pipe to a space which is flooding or likely to be flooded enables build up of pressure, limiting water ingress enables active de-watering if pressure can be added sealing air pipes can only be done by removing the vent head and fitting a plate of appropriate diameter and hole pitch/size to enable butting on good practice is to have 1,25’’pipe with gate valve mounted in the plate centre, enabling connection of compressed air and regulator at later stage only few vessels carry such plates onboard

45. Antwerpen - 2004 Jan D'Haeyer Slide 45 Pt.11: Damage evaluation- system capability systems are designed with a finite capability in mind also pumping, valve control, tank gauging, power supply systems once the design parameters are exceeded, the system’s operational capability will degrade seems obvious, but it is not so clear during emergencies effort to recover the situation with systems outside their design parameters shall not be fruitful list of normal parameters which should be obtained for each system and recorded in the Damage Control section of the Operations Manual page 593-594

46. Antwerpen - 2004 Jan D'Haeyer Slide 46 Pt.11: Alternative methods of damage control Approach to emergency: oilfield mariner: safety of the crew paramount has been trained in managing accidents and emergencies efforts to ensure that the crew are removed by boats, helicopters or any other means is given the first consideration professional salvor: keeping vessel afloat his skill is a continuous test of balancing the dangers (to men and equipment) against knowledge, experience and the application of the correct techniques designed to overcome the tendency to sink

47. Antwerpen - 2004 Jan D'Haeyer Slide 47 Pt.11: Alternative methods of damage control abandonment may be so risky and hazardous that it becomes an unrealistic option saving the crew will rely on saving the vessel, or at least delaying foundering will some methods applied by professional salvors can be usefully applied in these circumstances however such methods require initial preparation a degree of practice or training high degree of determination (fear, disorientation, panic is human)

48. Antwerpen - 2004 Jan D'Haeyer Slide 48 Pt.11: Alternative methods of damage control The use of compressed air - air balance a flooding compartment in free communication with the sea, can be partly de-watered by introducing air into the space via it’s air pipe when pumping may be impossible rapidly applied IF suitable fittings are made up which bolt onto the air pipe in place of the normal ‘top hat’ provided hatches and other access are probably sealed structural damage is unlikely (pressures used are low) diag 180 p.606

49. Antwerpen - 2004 Jan D'Haeyer Slide 49 Pt.11: Alternative methods of damage control The use of compressed air - air pressure deballasting an enclosed compartment can be pumped out via it’s normal fixed pipe work using air pressure induced into the space diag 181 p.607 ballast pipe work manifold valves are lined up to discharge overboard air pressure will force the water out via the only ‘escape’ air can be supplied from e.g. bulk air compressors on drilling units

50. Antwerpen - 2004 Jan D'Haeyer Slide 50 Pt.11: Alternative methods of damage control The use of compressed air - combined air blow & de-watering method of compressed air is of benefit only when water can be discharged somewhere very small spaces sometimes do not have a means of actually discharging the water solution: insert both de-watering line (spill line) and the air pressure line via the air pipe a length of steel tubing with the air line is run into the tank when air is applied, the water is forced out via the fill line and is lead overboard or to a suitably positioned salvage pump

51. Antwerpen - 2004 Jan D'Haeyer Slide 51 Pt.11: Alternative methods of damage control The use of compressed air - cautions hatches/accesses to compartments leaks are common as the hatch is pushed off it’s seal wise to rig up steel shores to resist pressure or weld strong backs across the hatch to strengthen it over pressure during de-watering Boyles law: ”if the temperature is kept constant the volume of gas will vary inversely as the absolute pressure while the density will vary directly as the pressure) as draft reduces, pressure decreases, air volume increases gauges and valve arrangement should be fitted

52. Antwerpen - 2004 Jan D'Haeyer Slide 52 Pt.11: Alternative methods of damage control Counter-flooding the professional salvor will attempt to prevent foundering due to progressive flooding by a combination of de-watering counterflooding he will carefully assess the possibilities of spaces not usually considered as ballast tanks if they might serve his purposes in terms of altering trim and list - diag 182 p.608 some compartments may serve this purpose, e.g. chain lockers, bulk silos can be readily flooded via existing openings or pipe work he might also apply the large amounts of weight available as fuel, fresh water, brines and base oil use of crossovers between ballast and other systems shows useful tanks and void spaces can be filled/emptied via air pipes

53. Antwerpen - 2004 Jan D'Haeyer Slide 53 Pt.11: Alternative methods of damage control Counter-flooding plans and procedures for filling and emptying such spaces can be thought out in advance and included in the vessel’s damage control data a variety of equipment is required in order to carry out above mentioned handlings: number of portable pumps, most useful double diaphragm air driven type (very high output, not sensitive to choking on suction side) hoses, fittings and air lines for such pumps etc. common is to have a dedicated locker containing such equipment example of equipment list of Damage Control Locker p.604

54. Antwerpen - 2004 Jan D'Haeyer Slide 54 Pt.11: Alternative methods of damage control purpose of counter ballasting controlling the trim, list and sinkage caused by damage flooding of space within the vessel it is a deliberate action with the aim of countering excessive trim and list counter ballasting plans counter ballasting plans can be prepared on forehand weather conditions, system failures and panic actions can result in necessary modification of a pre-planned procedure the less deck load in operating draft, the more ballast space is occupied, the less available for counter ballasting it is wise to make two sets of procedures, max & min load

55. Antwerpen - 2004 Jan D'Haeyer Slide 55 Pt.11: Alternative methods of damage control Techniques for counter ballasting assume that one or two spaces are flooding in the extreme end of one hull/column pump out water from tanks at the boundaries of the flooded space fill tanks in those spaces diagonally opposite the flooded spaces transfer ballast from the damaged hull to the intact hull transfer deck tank liquids from their position in the undamaged side - weight transfer transfer ballast from low side ballast tanks to high side tanks, or voids not normally used for ballast, if ballast capacity is used up head down trim, pump room aft: gravity flow ballast from forward tanks to midship tanks

56. Antwerpen - 2004 Jan D'Haeyer Slide 56 Pt.11: Alternative methods of damage control Stability considerations - practical aspects flooding damage lower hull area added weight under VCG, increase in GM due to draft increase, GM might decrease de-ballasting adjacent tanks or tanks above the damage, counter flooding diagonally opposite tanks, does usually not result in very significant changes in GM best option is to remove ballast from adjacent tanks

57. Antwerpen - 2004 Jan D'Haeyer Slide 57 Pt.11: Alternative methods of damage control Stability considerations - practical aspects flooding damage column area added weight i.w.o. VCG, possible decrease of GM reduced waterplane area, decrease of GM free surface effect further decrease of GM prior to de-ballast, calculate the virtual rise in KG/GM due to free surface in tanks being emptied and in the damaged compartment in any case, never use more than two tanks at the time in case severe damage or loading condition has reduced GM values if vessel is heavily trimmed (risk for downflooding) it is in considerable danger only way of increasing GM is by adding weight below CG and removing weight from above CG

58. Antwerpen - 2004 Jan D'Haeyer Slide 58 Pt.11: Damage Control Calculations Calculation example p.610-615 same method, EXERCISE:

59. Antwerpen - 2004 Jan D'Haeyer Slide 59 Pt.11: Damage Control Locker Conventional ships: SOLAS requires fire man’s locker containing b/a sets, protective clothing, torches, axes, …. most crew have assigned emergency duties (and all have stations) Semi-submersibles: emergencies are more complex ordinary fire man’s locker is limited in use 2/3 of personnel with non-assigned emergency stations search for and mustering of personnel is harder than on a passenger ship three widely seperated open deck locations for Damage Control Locker containing comprehensive damage control outfit (see list p.616-623) being the muster station for the fire teams