Blow-room.pptx yarn manufacturing system

yarn

1. CHAPTER-TWO BLOWROOM

2. Introduction Blow room is the first step of yarn production process in spinning mills. The name blow room is given because of the " air flow " and most process is done because of air flow. Basic operations in the blow-room are: Opening Cleaning Mixing or blending Micro-dust removal Uniform feed to the carding machine 2

3. Before starting the operation of blow – room the raw materials should have to exist in the extraction floor for 24/48 hours in a conditioned air; Temp above 23⁰ C and R.H of 45 – 50% ranges. If the air is damp, results in poor cleaning and if it is over – dry, leads to fiber damage . Blow room installations consist of a sequence of different machines to carry out the task of blow room operations. 3

4. Opening Is the first operation required in the blowroom line. Opening is the breaking up of the fiber mass into fiber flocks( tufts ) in order to removes the heavier impurities . Opening is illustrated by calculation of the theoretical tuft weight curve starting from the bale , up to the cylinder of carding . 4

5. The more intensively the cotton fibers have been individualized, The more contamination particles appear on the surface of the fiber bulk and may be removed. Target weights for the individualized flocks are about 0.02 to 0.03 g . Two stages of opening must be distinguished are: Opening to flocks: in blow room. Opening to fibers: in the card and OE spinning machine. Ways of opening: i . Breaking up of larger tufts into several smaller tufts to create new surfaces. ii. Opening up of individual tufts to increase the volume. 5

6. Plucking springs Spiked Roller Bladed Drum Roller With toothed disc Roller with Toothed disc having double edge Carding Roller Various opening devices used in blow-room 6

7. Three Bladed beater Beater with pinned bars (Kirschner Beater) Rollers with pinned bars(Kirschner Roller) Two Bladed Beater Cont… 7

8. Cleaning Cleaning is the removal of unwanted trash . For cleaning, it is necessary to open more and more surfaces by opening devices and then remove the impurities from the newly created surfaces. Light particles: Such as dust which are freed and can be removed by air currents . Larger particles: Such as leaf, seed, dirt, and sand are loosened, and some are sufficiently freed to be removed by beating the tufts against grid bars or perforated plates . 8

9. Various types of cleaning device used in blow room are; Grid bards: used for trash removal. Air flow: used to separate the trash from fibers. Suction devices: used for separation of trash and dust. Beaters: after the gentle opening by action of opposing spikes, beating action is performed. Flow diagram in the air stream cleaner Cont… 9

10. Some Technological points connected to opening and cleaning The larger the dirt particle, the better they can be removed. Higher the degree of opening results in higher the degree of cleaning. Higher roller speeds give a better cleaning effect, but also more stress on the fiber. Cleaning is made more difficult, if the impurities of dirty cotton are distributed through a larger quantity of material by mixing with clean cotton. The degree of cleaning is strongly dependent on the trash % . It is also affected by the size of the particle and stickiness of cotton. Due to machine harvesting , cotton contains more and more impurities, which furthermore are shattered by hard ginning. 10

11. Therefore, cleaning is always an important basic operation in modern blow-room . Mechanical action on fibers causes some deterioration on yarn quality, Particularly in terms of neps . By using a much shorter machine sequence , fibers with better elastic properties and improved spinnability can be produced. Air streams are often used in the latest machine sequence to separate fibers from trash particles, By buoyancy differences rather than beating the material against a series of grid bars. Cont… 11

12. Feeding devices There are three types of feeding apparatus in the blow-room machines; Two feed roller arrangement gives the best forwarding motion , But unfortunately results in greatest clamping distance between the cylinders and the beating element. Two feed rollers( clamped) 12

13. The clamping distance can be made very small . This gives intensive opening , but clamping over the whole width is poor , Because the roller presses only on the highest points of the web. Thin places in the web can be dragged out of the web as a clump by the beaters. 2. Feed roller and a feed table Cont… 13

14. Gives secure clamping throughout the width and A small clamping distance , which is very critical for an opening machine. 3. A feed roller and pedals Cont… 14

15. General factors which affect degree of opening, cleaning and fiber loss are: Fiber alignment Opening device Speed of the opening device Degree of penetration Thickness and density of the feed web Size of the flocks in the feed Type of grid bars Area of the grid surface and grid settings Ambient R.H.% and Ambient temperature etc. Factors which affect degree of opening and cleaning 15

16. Cleaning efficiency (C.E) of the machine is the ratio of the trash removed  by the machine to that of  total trash fed to the machine, expressed as percentage. C.E =   x100 Example : Amount of trash in raw cotton = 4% Trash in lap = 1.4% C.E = 2.6/4 *100= 65% Cleaning Efficiency C.E =   x100 Or, 16

17. Mixing or Blending If different grade of same fibers are kept together. The reasons for mixing are; Price optimization To facilitate the process Improve the properties and others. Some types of Mixing: Hand stock mixing Mixing by hopper Lap mixing Card mixing Mixing: Proper mixing in blow-room takes care of the variations always present; Between and within bales of same and/or different typ e of cotton and maintain a uniform yarn and fabric quality. 17

18. To ensure this, it’s necessary to follow these rules: To ensure feeding of thin layers from each bale . To take maximum number of bales from 40 to 70 (up to 180) bales depending on length of machine and bale size. Use of good mixing machines in the blow-room line. To go for stack mixing , if possible, Why? Because; It is preferable compared to automatic bale openers, Tuft sizes can be as low as 10 grams and It’s the best way of opening material ( neps creation will be less ) Contaminations can be removed before mixing is made The raw material should get acclimatized to the required temp and R.H.%, 18

19. 19 It is better not to use the following cottons: Cottons with inseparable trash (very small size), even though the trash % is less. Cotton with low maturity co-efficient Sticky cotton The fiber gets conditioned well or more than 24hrs in opened state However , some of the disadvantages of stack mixing are: More labor is required More space is required

20. When different fibers of same or different grades are kept together. Stage of blending operation Metering : determining the quantity of individual components. Mixing : bringing together the metered quantity. Intermingling : distributing the components evenly in the body of fibers. Some types of Blending: Hand stock blending Lap blending Card blending Draw frame blendin g Blending: 20

21. Micro-dust removal Cotton contains very little dust before ginning. Dust is caused by working of the material on the machine through shattering of impurities and smashing and rubbing of fibres. Dust removal is not an easy operation, Since the dust particles are completely enclosed within the flocks and therefore float with the cotton in the transport stream. If they are to be eliminated they are to be rubbed off. The main elimination points for adhering dust are those points in the process at which high fibre/metal friction or high fibre/fibre friction is produced. Release of dust into the air occurs wherever the raw material is rolled , beaten or thrown about and then removing the dust-contaminated air. 21

22. Accordingly the air at such positions is sucked away . Some of the instruments used to remove dust are; Perforated drums Stationary perforated drums Stationary combs etc. Almost all manufacturers of blow-room machinery now offer dust-removing machines, or equipment in addition to opening and cleaning machines. Uniform feed to the carding machine At the end of the cleaning line, 40 to 50 % of impurities are removed (largely heavy particles), and The opened material is then uniformly fed into the carding process. 22

23. Actions of blow room Action of opposing spikes : It is principally for opening action of the fiber tufts, Because, i f beating action at the starting stage may damage the fibers. Action of beater and grid bars : It is gives both opening and cleaning Action of air currents : It is used for cleaning & transport of material within the blow-room Regulating action : It is used for formation of a regular lap or homogeneity and to ensure the formation of regular yarn. Action of gravity and centrifugal force : Remove the heavy trash particles from cotton through the opening of grid bars. 23

24. Rieter blow – room, and carding line: Bale opener A11 UNIflock Pre-cleaner B 12 UNIclean Homogenous mixer B 75 UNImix Storage and feeding machine A 78 UNIstore A 21 Condenser C 60 card CBA 4 Sliver Coiler Cont… 24

25. High performance blowroom line comprises: Cont… Opening to fine flocks Removing coarse trash and dust in free flight Homogeneous blending Removing finest trash and dust with intensive opening 25

26. Sequence of operation in blow-room Since blow-room machines have to fulfill various functions, they also vary in concept and design. Basically the following types of machines are found: Bale Opening machines Cleaning machines Mixing machines Dust extraction machines Metal, fire and foreign fiber (optional) detection machines. Either lap formation unit or Chute feed to card 26

27. Bale opening (Pre-opening) Zone-1 Coarse Cleaning (Pre-cleaning) Zone-2 Mixing or Blending Zone-3 Fine opening and Cleaning Zone-4 Chute Feeding or in some cases lap formation in scutcher Zone-5 It mainly consists five common zones of processing. The five common zones of processing in modern blow-room: However, several manufacturers now offer special dust removing machines. In machine sequence, they appear mostly at the end of the blow- room line. Modern blow - room line 27

28. Zone 1: Bale-opening (pre-opening) Effective pre-opening results in smaller tuft sizes. Thus, creating a large surface area for easy  and efficient removal of trash particles by the fine openers. The machine of this zone should be able to; Extract the material evenly from the bales Open the material gently Open up to the smallest and equal size flocks Process as many bales as possible in a single charge Blend material right at the start of the process Permit the composition of a fiber blend from several components (fiber origins) 28

29. Bale opener machines mainly classified in to two category: ii. Automatic bale opener i . Classic/Conventional Hopper Bale Breaker(older- openers) Cont… 29

30. Is machine known under several manufacture names such as: Bale openers, blending openers, blending bale openers, mixing openers, waste openers. Previously, these were the standard bale openers ; in newer installations, however, they are found mainly as waste feeders or for opening and blending of man - made fibers . I. Classic/Conventional bale openers Cont… 30

31. Working principles of classic bale openers The strand moves in to conveyor belt . Opened layers of fibers by opening roller in plucking unit are delivered in to feed belt . It inters the spiked lattice covered with low intensity spikes for opening purpose. The take - off roller takes the opened tufts and the gap between the roller of inclined lattice and the take – off roller determines the tuft size . The delivered tuft goes in to opening roller that covered by knife grid . Cont… 31

32. If Spike Lattice Action used for bale opening: The inclined lattice speed and the setting between inclined lattice, and clearer roller decides the production of the machine. The setting between inclined lattice and clearer roller decides the quality of the tuft. If  the setting is too close, the tuft size will be small, But, the neps in the cotton will be increased due to  repeated action of the  inclined lattice pins on cotton. It is easier to remove the bigger trash than the smaller trash, So, enough care should be taken to avoid breaking the trash particles. It’s open the tufts into small sizes, t herefore, cleaning becomes easier in the next machines. The fiber tuft size should be  preferably 100 to 200 milligrams. 32

33. Automatic Bale Openers It extract smaller tuft sizes , thus creating a large surface area for easy  and efficient removal of trash particles by the fine openers. Working width of 1720 mm and a machine length of 50 m , about 130 bales can be accommodated (one or two sided). 33

34. It helps to maintain the homogeneity of the long term blending. The latest automatic bale opening machines,  the tuft size can be as small as 50 to 100 grams without  rupturing the fibers. The opening roller speed should be around 1500 to 1800 rpm. The depth of penetration of the opening  should be as minimum as possible for better quality. Production rate of the machine depends on: The number of mixings working at the same time, Opening roller depth, Traverse speed and fiber tuft density in the bale. 34

35. Main components of Automatic bale opener: Control unit, Fiber bales, Working head with tooth discs, Swivel tower, and Air duct for material transport. Cont…

36. The opening machines are not fitted with cleaning devices or they can eliminate only a fraction of impurities due to high material throughput. So to remove impurities from the surfaces presented, high performance pre-cleaners are require with high capacity. If pre-opening and pre-cleaning are done properly,  consistency in trash removal by fine openers is assured. The fiber treatment in zone-2 machine is very gentle, Because the fibers are not gripped by the feed roller during beating.   Zone 2: Coarse-cleaning (Pre-cleaning) 36

37. All heavy trash particles fall down before they are broken such as, seeds (full seeds) fall in this machine without any problem. The optimum cleaning means maximum cleaning performance, minimum loss of good fibers, a high degree of fiber preservation and minimum nep generation. There are various types of pre-cleaning machine like: Step cleaner The dual roller cleaner Rieter former monocylinder cleaner Rieter B 12 UNIclean Cont… 37

38. Step cleaner or 6-step cleaner The working principle of Step cleaner The material falls into the feed hopper and pass to the first beater . From there it is transported upward by the six beater roller , each carrying profile bars ; the beaters are arranged on a line inclined upward at 45⁰ . Elimination of impurities takes place during the continual passage of the material over the grids arranged under the rollers. 38

39. Some step cleaners have a high flow chamber with special baffle plate to improve cleaning intensity. The grids are always adjustable and usually also the beater speed . Cont… 39

40. This model mainly includes: Marzoli B39 and AXI-FLO ( MFC) Trutzschler's. The Dual Roller Cleaner Trutzchler MFC Marzoli B39 40

41. The machine comprises a large cleaning chamber containing of 610 mm diameter rotating in the same direction. A fan downstream from the dual roller draws material through the machine by suction. The first opening roller caries the material over the grid three times before it passes to the second roller. Trash falls onto the bucket wheel locks . The guide sheet in the hood direct the tufts. The working principle of dual roller cleaner Cont… 41

42. Rieter Former Monocylinder Cleaner The working principle: This machine operate in a similar manner to the dual roller cleaner but has only one drum. The material enters the machine at one side and flows through ( parallel to the beater ) to the other side. In order to prevent tufts from being drawn straight through the machine, the large hood above the drum is divided in to three chambers by guide plates. 42

43. This causes the tufts to fall back in to the region of the beater drum after being hurled out by the roller. In this way, the tufts are forced to circulate three times with the drum, i.e. pass three times over the grid ; this produce intensive cleaning effect. The grid is in two parts, these are separately adjusted. Cont… 43

44. Rieter B 12 UNIclean The working principle: The basic design corresponds to that of the monocylinder cleaner . But instead of the material rotating three times inside the machine, it is forced to pass over the grid five times , always presenting new surface areas to it. The tufts not only pass over the grid five times, they also over the specially arranged perforated sheet five times. The chamber behind this sheet is a low pressure chamber. 44

45. The air suction through this sheet provides very effective dedusting . The waste is collected inside the machine and feed to the waste transport via an air lock cylinder . Intermittent suction and connection to continuous suction is possible . The air lock prevents good fibers from being sucked through the grid during waste removal . Cont… 45

46. Calculation of machine production and number of beaters of blow-room To assess the opening action of a beater, refer to its intensity of opening. The intensity of opening is an estimate of the tuft size in milligrams per one striker a beater for a preset production rate & beater speed. Where I = intensity of opening (mg) P = production rate (kg/h) n b = beater speed (rpm) N = number of strikers 46

47. Zone 3:Mixing and Blending Barred or streakiness in fabric arise due to uneven mixing of different cottons. Mixing technology is important factor in spinning mill technology. Bigger the differences of cotton parameters like fineness , color and staple length, the greater the importance of mixing. If the cotton has honeydew, the intensive mixing of the raw material is a precondition for an acceptable running behavior of the complete spinning mill. There are various types of mixing/ blending machines: MCM/MPM Multiple Mixer (Trutzschler) Rieter B 70 UNImix Reiter A 81 UNIblend 47

48. Trutzschler MCM/MPM Multiple Mixer It comprises ( 6-8 ) adjacent chute chambers in to which the material is blown from the above. The chutes are filled successively and material is removed from all chutes simultaneously . This gives a good long – term blend. The Working principle: 48

49. Ejection of tufts onto a collecting conveyor is performed by take – off and beating rollers under the chutes. The filling height in the chutes is held fairly constant by sensors . At the end of the machines a simple suction system or a cleaner cab be incorporated. Cont… 49

50. Rieter B 70 UNImix This machine consists three basic sections: A storage section An intermediate chamber and A delivery section. Parts: Feed chute Guidance system into the blending chamber. Upright lattice Opening roller Take-off roller Delivery chute 50

51. The Working principle: Tufts are feed pneumatically and simultaneously in to eight chutes (2). A conveyor belt feeds the stock through the intermediate chamber to the spiked lattice (3). The material columns then diverted from vertical into horizontal. i.e. there is 90⁰ deflection in the material flow materials. Cont… Parts: Feed chute Guidance system into the blending chamber. Upright lattice Opening roller Take-off roller Delivery chute 51

52. It results in condensation and produces a shift in timing and spatial distribution of the fiber package from the first to last chute. This special construction with 90⁰ deflection and thereby different distances from the individual chutes to the lattice in turn results in good long-term blending . Cont… 52

53. Thereafter, the material subjected to a further opening step between inclined spiked lattice and evener roller (4) Short - term blending. An optical sensor ensures that only a small quantity of fiber stock is held in the mixing chamber in front of the lattice. Behind the spiked lattice there is a take - off roller and a simple pneumatic suction feed the mixed chute to the next machine. Cont… 53

54. All the above machines create random blends . i.e. they are excellent machine for blending of one type of material (although with some varieties), e.g. cotton , or only one shade . However, they are insufficient when blends of different materials (e.g. cotton/polyester ) or different colors are required. These blends are produced mainly on draw frames , but can also produced on the blow room line . For this special cases Reiter offers it’s A 81 UNIblend machine. 54 Cont.…

55. The Working Principle of Reiter A 81 UNIblend Different materials are feed from different chute/feed . Then every chute ends at the bottom with an independent metering device . Each chute therefore drops a precisely measured quantity of material on to conveyor belt . The conveyor belt then forwards the accurately metered stock to the take-off unit. Parts: Material feed Dedusting and air extraction Air to filter unit Dosage unit Component layers Take-off unit Inverter-controlled transport fan Control cabinet 55

56.   Zone 4: Fine cleaning In contrast to zone-2 machines, zone-4 must again produce new surfaces, and As far as possible very small tufts with large total surface area. Zone-4 machines always operate with clamp feed. The spacing of the striker elements on the rollers must be finer. Single roller cleaning  machines are used, depending upon the  amoun t and type of trash in the cotton, The number of fine cleaning points can be either one or two.  Normal beater speeds with single roller saw-tooth beater depends upon the production rate ,  fiber micronaire and trash content . The number of wire points depends on the production rate & trash. 56

57. Setting b/n feed roller and beater depends on the production rate and micronaire, The setting should be around 2 to 3 mm . Closer setting b/n beater & mote knives higher the waste collected. It is advisable to keep around 3 mm. Type of cotton Cotton micronaire Production rate kgs/ hr Beater speed Rpm More trash 3.5 to 4.0 200 to 300 kgs/ hr 600 to 750 Less trash 3.5 to 4.0 200 to 300 kgs / hr 600 to 750  More trash 4.0 to 4.5 200 to 300 kgs 700 to 850 Less trash 4.0 to 4.5 350 to 500 kgs 1000 and above Cont… 57

58. Rieter B 60 UnIfelx/ Fine Cleaner The Working principle: A fun draws the tufts by suction from the preceding machine and a distribution element ejects it into a filling chute (1). The rear wall of the chute consists of individual aluminum lamellae with stop-opening through which the air can escape ( first dedusting step ). Parts: A filling chute Perforated drum Feed trough Grid Opening cylinder Delivery pipe 58

59. The material is carried further by perforated drum (2) ( second dedusting step ). The feed trough/ roll (3) supplies the material to the opening cylinder (5),the gap between them is adapted by the programming to the material being processed. A grid (4) made of carding segments and knives forms the cleaning surface and extract impurities. Cont… Parts: A filling chute Perforated drum Feed trough Grid Opening cylinder Delivery pipe 59

60. Cont… The carding segments on the knives increase the degree of opening and consequently the cleaning . The spinner can set and adjust the rotational speed of opening cylinder and the setting of knives on the grid according to his objective and raw material. By using Varioset . 60

61. Zone 5: Chute Feeding In addition to, the other functions of blow room machines, th e scutcher has to form a lap/sheet for supplying material to the card. Previously, most these machines were double scutchers with two beater positions and two pairs of perforated drums. Recently, almost exclusively single scutchers with one beater position and only one pair of perforated drums or single drum. The volume of sheet calculate; V = v*h*b Where; V= the volume of cotton fed into the machine in unit of times v = is the rate of feeding the sheet of cotton to the next machine h = is the thickness of the sheet and b = is its width 61

62. De-dusting: Apart from opening and cleaning of raw-material, de-dusting is the very important process in blow room. Indeed, de-dusting   starts with pre-cleaning and this is done along with trash separation in many machines. Exhaust fan speed and volume should be accordingly selected. DUSTEX or some other special de-dusting machine should be installed before feeding to the cards, Because, better the fiber  opening better the de-dusting. Cont… 62

63. 1.Cleanomat cleaner 2. The infeed of the tuft 3. Perforated sheet 4. Withdrawal of the material due to suction system to the card 5. Separated dust permanently Rieter Dust Extractor 1& 2. material passage 3. Suction system Trutzschler DUSTEX Cont… 63

64. Rieter A 78 UnIstore Machine Parts: Material input Material discharge Opening rollers Feed rollers Perforated metal plate for air discharge Light barrier for monitoring material height Open exhaust air transfer It used as a storage , dedusting and feeder machine in blow room. Its main purpose is to provide intermediate storage for material in order to ensure trouble-free blow room operation. Long piping distances are frequently found to interfere with smooth running of the process and an intermediate storage is necessary in many case. 64

65. It is used where a mixing opener proves unsuitable for financial, technical or technological reasons. The integration of a mesh screen filter inside the machine eliminate the transport air , and creates an efficient dedusting . The structure of the feeding and opening unit guarantees gentle fiber opening . Cont… Parts: Material input Material discharge Opening rollers Feed rollers Perforated metal plate for air discharge Light barrier for monitoring material height Open exhaust air transfer 65

66. Associated equipment Magnetic extractors: This is used in order to remove ferrous metals mixed with material. Fire eliminators: This comprises spark detectors and eliminating device . Foreign matter detectors: It would intercept/prevent foreign matter during opening and cleaning. It is carried out at very beginning of the spinning process in order to prevent fibrous contaminants. 66

67. Color Detectors These systems are based on CCD camera or electro-optical sensor technology. Cotton tufts are scanned while being conveyed by airflow and contaminated lint is separated via diverters or compressed air nozzles . Schematic view of Securomat SCFO CCD color line scan camera with compressed air ejection nozzles 67

68. A CCD color line scan camera monitors the surface of a rotating spiked cylinder . Among the tiny tufts and individualized fibers present on the cylinder surface, even the smallest contaminants are exposed and distinctly presented to the camera system . Upon exceeding certain camera signal limits , pneumatic valves and compressed air nozzles are activated and the foreign object is ejected into the waste duct. The Working principle of Color Detector 68

69. Metal Detector Metals and sparks are mainly detected by using either of the following machines: Magnetic metal extractors (Marzoli) Electronic metal extractors (Trutzchler) Combo Shield (Rieter) 69

70. Magnetic metal extractors Magnetic metal extractors (Marzoli) Magnets have been used in ducting or special parts of machines in order to eliminate pieces of ferrous material . The most effective form of device is a knee-bend within the feed duct having permanent magnets at the two impact surfaces. When the tufts are driven against the magnets , ferrous particles are retained and can be removed from time to time. 70

71. Magnetic extractors provide only partial solution to the problem; Because they can eliminate only magnetizable metal particles , and let all others pass. Magnetic metal extractors (Marzoli) Cont… 71

72. The material is fed from an opening machine such as Blendomat . A fan in front of the mixing machine, extracts the material by suction (5) Spark sensor (2) detects smoldering material and metal detector (3) any kind of metal. Electronic metal extractors Electronic metal extractors (Trutzchler) 72

73. In either case, active operating flap (4) is opened by a single from the detector and feeds the material into the receiving waste container (6) , Which is equipped with a fire extinguisher device (7) and a temperature sensor (8) to monitor the container. Cont… Electronic metal extractors (Trutzchler) 73

74. Some general recommended process conditions in blow-room It is advisable to run the fans at optimum speeds .  Higher fan speeds will increase the material velocity and will create turbulence  in the bends and increase neps in cotton. It is advisable to reduce the number of fans   in the line.  All blow-room machines should work with maximum efficiency. The feed roller speeds   should be selected in such a way that  it works at least 90% of the running time of the next machine. Heavy particles like metal particles, stones should be removed using heavy particle removers, double magnets etc., Before, they damage   the opening rollers and other machine parts. Number of cleaning  points are decided based on  type of ginning, amount of trash, number of trash particles and type of trash particles. 74

75. Machinery selection should be based on the type of cotton and production requirement.  Material level in the storage chambers should be full  and it should never be less than 1/4 th level. Grid bars should be inspected periodically , damaged grid bars should be replaced and front rows can be replaced earlier. If the cotton is too sticky, the deposits on the machine parts should be cleaned at least once in a week, before it obstruct the movement of the fiber. Fiber rupture should be checked for each opening point.  Nep increase in the blow-room should not be more than 100%. The nep increase in each opening machine should be checked  with different beater speeds and settings, and the optimum  parameters   should be selected. Cont… 75

76. But , it is necessary to remember that everything should be based on  yarn quality checking. Blow room machinery lay out should be designed in such a way that there should be minimum number of bends, and There should not be sharp bends   to avoid fiber entanglements.   However, sometime it may be desirable to go for combination of machines from different manufacturers. 76

77. Blow-room production calculation = Surface speed of Shell roller * lap weight * time * No. of Scutchers * Eff. 36 * 16 oz/ lb Gearing diagram of blow room Cage condenser Production 77

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