MODERN DEVELOPMENTS IN BLOW ROOM
MONO CYLINDER CLEANER.
Object : To open and clean the cotton.
Advantages : Impurities are separated without being crushed.
This proves favourable during subsequent operations.
Type : Loose feeding pin opener.
Type : Loose feeding pin opener.
The well opened tuft of cotton from mixing bale opener enter the machine at right angles to the pin cylinder axis.
The pin cylinder has 8 rows of six pins each, arranged spirally -around its circumference.
Due to the collision of the cotton tufts with rapidly revolving pin cylinder against grid bar, impurities from cotton is extracted and passed through the spacing of the grid bar.
ERM- Cleaner -Universal opening and cleaning machine
Object : To open and clean the cotton.
Type : Gripped and controlled feeding & saw toothed disc opener The fibre is blown into the laminar chute by an integrated fan. The filling of the chute is monitored by 2 photocell. Thepair of spring loaded feed roller in it ensure a controlled feed of the fibre tufts. Due to the heavier beating of the rapidly revolving saw toothed disc on cotton tufts against knife grid, highest possible degree of opening and cleaning of the fibre is achieved.
By means of graduated lever, the grid bar can be adjusted regarding spacing between the knife grid bar & brought into proper position relative to opening Roller according to handle any degree of impurities and opening in the cotton to be processed. It is thus possible to adjust amount of waste and its quality to the requirements of different types of material.
After opening and cleaning, the material is conveyed pneumatically through outlet pipe to the next machine.
Axiflo cleaner or spiro cleaner
Object : To open and clean the cotton.
Type : Loose feeding pin opener, Major cleaning point.
The coton is drawn into the Axi-Flo machine through inlet Pipe. The construction of the two beating cylinder with grid bar arrangement, is clearly shown in figure.
Opening and cleaning of cotton is achieved by the repeated beating action of the rapidly revolving two beating cylinder on cotton against grid bar. Trash particles from the cotton is extracted through the grid bar and is collected below the grid bar.
Smaller tufts that are already sufficiently opened for a quick and thorough cleaning, thus leave the Axi-flo earlier without receiving unnecessary beating. This prevents loss of good fibre, formation of neps and fibre entanglement. Fibre contained in large tufts cannot get entangled or lost through the grid. They remain in the machine till they are transformed in to small tufts and release their impurities easily.
An adjustable guide plate fixed to the inlet pipe control the angle at which the tufts approach the right beating cylinder.
This cylinder takes the tuft downwards, guides them over the broad waste grid and throws them up against the adjustable defector plate. The defector plate directs the tuft stream within t he reach of the left cylinder which then passes the material over its own grid and transfers the 1arger tufts back to the right cylinder. The position of the adjustable guide plate between the two cylinders decides how long the tufts remain under the influence of each cylinder.
The angular position of the bar is adjustable for each set separately. Each set of grid bar can be raised or lowered to alter the distance between the grid to the end of the spike. It is thus possible to adjust the amount of waste and its quality to the requirements and the different types of raw material.
PORCUPINE BEATER
(Improved porcupine opener)
Object: To open and clean the cotton.
A controlled motor with an infinitely variable speed unit drives a star roller and a pair of feed roller. Star roller drive the material from the delivery funnel of the preceding machine to the feed roller. Pair of feed rollers are fluted and spring loaded.
The beater blades have double notched and bolted to the cylinder in pairs. This types of fixing is rigid and no vibration during beating action, so, beating is accurate and definition. In conventional porcupine opener, individual striker blades are revetted and they are not very rigid due to the free length of blades and method of fixing to the discs.
The waste grid consists 25 specially profiled steel bars and can be adjusted during operation. A graduated scale helps the repositioning for favourable settings.
The sheet of cotton delivered from the cage deliver roller runs almost horizontally through the calender, as shown in the fig. By this arrangement a wider surface pressure is achieved, enabling higher compression of the sheet of cotton (LAP) without endangering the fibres. And also eliminate cracking of lap surface and false draft which occur when lap would have to run around the calender roller in a vertical position in the conventional scutcher.
Lap colour coder: Every lap receives a washable colour spray marking on its side. This marking may be given a definite meaning eg blend, the number of the scutcher etc., laps out of tolerance receive an additional marking with another colour.
Automatic lap doffing mechanism
As the rack penion rotates in clock wise direction it will press the projection sl ,which operate the micro switch MC2. MC2 is a reversing switch for rack motor. So, the racks moves downwards, loading arm will bring the lap spindle and place it in between two shell roller. When the rack moves in down ward, the rack penion rotates in anti-clockwise direction & press the projection S2/ which operate the microswitch MC3. MC3 putoff the rack motor.
The separating head arranged in the horizontal closed circuit loop divert the part of tufts from air current into vertical feed chutes above the card inlets. Vertical feed chute ensures a uniform supply of material over the full working width of the card. Uniform separation of the tufts from the air current is achieved by adjusting the nose in the separating head. Raising the leading edge produces more separation and vice versa.
Advantages of flock feeding or chute feed sytem :
Disadvantages or limitations of chute feed system :
1. Loose feeding (free beating points)
2. Semi-fast gripped feeding(controlled feeding)
Proper speeds & settings:
Factors affecting the lap rejection and theCV % of 1 metre wrapping of lap & causesfor high lap weight variation
Defects in Blow room and causes.
Causes for Nep formation in Blow room;
3. Causes for curly cotton:
4. Causes for lap licking :
5. Causes for conical lap:
6. Causes for Soft lap
Control system in Blow room
Salient feature of modern mixer :
Electronic feed regulator motion in Blow Room
2. Efficiency = 80 % BCR delivery = 7 met/min
3. In a scutcher BCR dia is 17.78 cm worm on BCR is single, change pinion on the side shaft is 16 teeth, worm wheel on side shaft is 22 T, knock off wheel is 45T calculate lap length and also change wheel required to produce 38.38 metres of lap (42 yards) if the weight of the lap is 434 grams/mt and time taken to produce the lap is 5 min. Caluculate the production per shift of 8 hours. 1. Lap length = ? BCR Dia = 17.78 cm or 7 inches For one rotation of the knock off wheel one lap is completed.,
iii) Time taken to produce one lap = 5 min.
No of lap produced / 3 hr = 96 lap
Lap weight = 434 grams /metre
AUTOMATIC SCUTCHER
Construction of the automatic scutcher is clearly shown in the figure. Condenser with fan suck the material from opening line and feed to reserve trunk of the pneuma feeder. An adjustable photo electric cell in the reserve trunk monitor the height of fibre and signals stop or start commands to the preceding machine.
Delivery roller guide the material to a coarse spiked opening rol1er without compressing it too much. This opening roller beat and open the cotton and then flings the tufts into an air current generated by a fan. The air current transports the tufts into the feeding trunk. There they are compressed uniformly across the full width by the pressure of air current.
Feeding trunk width can be adjusted according to the fibre bulkiness. An adjustable, sensitive pressure switch located with in the feeding trunk monitor the height of fibre and switches off or on the material transport from delivery roller.
Much narrower limits of density of stock are obtained in the feeding trunk than unstable condensation of a conventional hopper feeder. So, scutcher receives a very regular feed in its absolute weight in width and length. No nep formation due to absence of spiked lattice.
Uniform feed to the scutcher due to effective control by P.E. Cell in the reserve trunk and pressure switch in the feeding trunk.
Two delivery rollers in the scutcher take over the material from the feed trunk. They pass it on to the feed roller which in turn passes it to the sensing levers and the kirschner beater.
An integration of the sensing lever movements control the position of the cone regulator. The movements of the cone belt from its basic position actuate a differential drive. It regulate the speed of the feed roller in a definite ratio to the constant speed of v-belt drive for the transfer of drive to the feed roller.
Press button switches are provided for the regulations of the lap weight per yard through servo motor on the P.I.V. drive. The current position of the PIV drive and degree of regulations are clearly indicated on a scale. It is possible to determine the setting very quickly in case of blend or count changes overs. In case of fully automated scutcher, only the basic lap wt/yard is set by using corresponding press button switch. All later adjustments are carried out by the lap weigher.
The fine opening & ultimate cleaning is achieved by the mild combing action of kirschner beater on cotton tufts.
The grid under the kirschner beater can be adjusted by manual setting of a hand lever provided with an index plate, and completely closed while processing synthetic fibres. The first four of ten grid bars are separately adjustable.
A compact, one layer lap collects on the dust cage with a large surface area. In this manner with a dia of 55 cm cotton lap of 40 kg and synthetic fibre lap of 24 kg can be prepared which unroll with out any peeling on carding.
A strong fan exhausts the cage diametrically across its whole width. This ensures a uniform distribution of the material across the cage and also a careful extraction of the dust.
The calender rollers are loaded pneumatically. This ensures always even pressure on both sides. The applied pressure can be read on a monometer and steplessly regulated to 6000 KP by a pressure reduction valve.
The machine stops on the entry of thick places of foreign bodies between calender roller. This eliminates break downs.
Rack heads are pneumatically loaded. The applied pressure can be steplessly regulated upto 100 KP and can be read on a manometer.
Latest automatic lap doffing:The required length of lap is pre-set by means of counter with decimeter setting. The impulse for lap change is given by limit switch, as soon as the lap attains a definite diameter. Immediately upon reaching the required lap length, the counter jumps back to preset length.
A 0.75 kw, 105 RPM reduction gear motor accelerate the lap roll in order to cut the lap. Simultaneously the pressure cylinder for the loading of the rack heads is counter ventilated. The rack heads rise and deliver the completed lap into the lap. tray. The lap spindle from the stand-by postion is placed on the forth coming lap. The beginning of the lap is tightly wrapped around the lap spindle. Rack heads are reloaded. The preparation of new lap begins.
By ventilating the pressure cylinder, the lap tray together with finished lap is moved sidewards. The lap together with the lap rod is completely stripped off the lap spindle. The lap Spindle rolls to the stand-by position where it waits ready for next lap doff.
LAP rod inserter: During the sideward movement of lap tray, the lowest lap rod from the rod magazine, that accomodate 20 lap rods, is released and inserted into the lap spindle of the lap under preparation during the return movement of the lap tray.
Lap weighter: The lap rolls into the tray of a lap weigher or a lap reserve tray the lap weigher register the lap weight deviation from the nominal weight on the register tape of the recorder and gives the impulse to the lap colour coder.
Simultaneously it indicate the deviation on a dial. Should the deviation from the nominal weight be large than the predetermined tolerance, the lap weigher gives an impulse to the servo motor and PIV gear that readjust the lap unit length weight to within acceptable tolerances.
Lap store: Depending on its size, the lap store automatically takes over 6 or more weighed laps. It is also possible to couple 2 or more lap stores in tandem. The lap store can also be connected to automatic lap conveyor system.
Automatic lap doffing mechanism
The construction of the various parts of the auto lap doffing Mechanism is clearly shown in fig.
Ratchet & pawl is Provided in lap length measuring motion.
A graduated disc is provided along the ratchet. On the graduated disc, a projection is given which rotates with the ratchet the same ratchet shaft, the rack pinion and two shoe projection s1 & s2 are fixed.
The graduated disc and projection in it (lap length measuring motion) is set in such a manner that as soon as the lap attains a required pre-set length, it will start the lap doffing device i.e., projection press the micro switch MC4.
MC4 release the brake and start the rack motor when the brake the released, the lap is detached by speeding up the shell roller (at the time of doffing only) by the operation of separate micro switch.
As the rack motor is started, Rack moves upwards, the rack penion rotates in clockwise direction. As the rack moves upwards, full lap is ejected by ejector arm and will drop on the lap tray. When the racks in the top most position, a pair of loading arm (fixed with rack) will take the spare lap spindle from the reserve position.
Brake is applied and shell roll motor is put off which speed up, the shell roll at the time of lap doffing only. In the first stage of operation, the graduated disc is reversed & put back to its normal position. The beginning of the new lap sheet is folded by the folding handle and lap is wound around the lap spindle and it is leaded again.
All the above operations are completed with in a few seconds while the machine is continuous to run without any interruption. This makes non-accumulation of material at the dust cages during the lap changing, thus no thick and thin places in the lap. results. The production is also increased by 10% at the same working speed, since the m/c is not stopped for 1 lap changing, High reliability in operation due to the greatly simplified and improved automatic changing.
Thus a uniform and even lap with good compactness is produced in the scutcher. Also work of the operative is reduced, so it is possible for one operative to attend more number of scutcher.
CHUTE FEEDING OR AERO FEED SYSTEM
Chute feed is a system of feeding small tufts of cotton fibres directly from blow room to a series of cards, arranged in a circuit through pneumatic pipe.
A condenser in the pneumatic pipe sucks the material from blow room and delivers it to the flock feeder through pneumatic pipe by way of the filling trunk.
Photo electric cell in the filling trunk regulates the supply of material from blow room. From here, the material is fed to the kirschner beater by way of two ridged roller and two feed rollers. Krischner beater open the cotton into desired size tufts.
A fan blows the tufts from the kirschner beater into horizontal c closed circuit loop situated above the cards. The return trunk has the duty of returning the surplus material(after the supply to last card) to the beater that also of uniting well opened material with supply of fresh material thus delivering it directly to the horizontal duct again.
The weight of the card f,eed per meter depends on the static excess pressure in the installation. This drops practically linear from separator to separator by about 2mm head of water. The weight of the feed per unit length must be adjusted in
accordance with this drop by increasing or deducting the distance between the glass front and the rear wall of the feed chute. The weight per meter ranges between 600 to 700 gms.
Thus while deviation of the card sliver count from one card to another must be regulated with the glass plate. The specific count of the sliver itself must be adjusted with the count change wheel.
Card Feed Chute: The feed weight at the card depends on the static pressure in the aerofeed system and the chute depth adjusted. Since the pressure diminishes from one feed chute to another, the chute depth must be matched accordingly. It can be varied from 80 mm to 120 mm and is read off on the scale at the arrow mark.
Advantages of flock feeding or chute feed sytem :
The automatic continuous feed directly linked to the blow room eliminates the lap formation. This increses the working efficiency of the blow room.
The main power requirement in doffing the lap, weighing, transportation to card and feeding at the card is eliminated.
The processing of rejected laps in the blow room is avoided.
The fibres are fed to the card in loose sheet form as against compressed form so that trash particles can be easily extracted from fibres by the carding action.
Excessive sliver irregularities due to the lap licking during high humidity, double lap feeding, lap splitting, lap piecing etc, are eliminated.
When compared to lap fed, there is a reduction of 1 % CV flock feeding card sliver.
Crushing of foreign materials seed bits and other tras| particles during calendering and difficulty of removing a subsequent processes is reduced.
Disadvantages or limitations of chute feed system :
Blow room should run the same number of hours per week as the cards do.
The card production must be kept excessive to assure continuous feed to drawframe at the time of stoppages at blow room due to maintenance and other unavoidable problems
Chute feed system control short term variation but not the medium and long term variations.
A reliable check on the nominal count can be established in lap forming system by controlling total lap weight and C.V. value of the weight per unit length. There is no such control in the chute feeding system.
Change of mixing will result in more waste in chute feed.
Proper selection and positioning ofmachines in blow room line
Feeding techniques of all the opener and cleaning machines can be broadly classified intotwo types.
1. Loose feeding (free beating points)
Examples: Vertical opener, step cleaner, mono cylinder, S.R.R.L. Opener,Axiflo cleaner, etc. ,
2. Semi-fast gripped feeding(controlled feeding)
Examples: Porcupine opener, 3 bladed beater, ERM cleaner,etc., Loose feeding beatingtechnique is employed in the initial cleaning line so that heavy impurities are removed, otherwise they will be crushed into fragments while fed into gripped feeding through pair of feed roller and it is very difficult to Remove crushedimpurities.
Certain machine gives its best in terms of cleaning efficiency, it must be fed with materialthat has been preopened to a certain degree.
The kirschner beater is a minor cleaning point and because
of its intensive combing action and it improve the evenness and
texture of lap. So it must be placed as the last machine of the
scutcher.
of its intensive combing action and it improve the evenness and
texture of lap. So it must be placed as the last machine of the
scutcher.
Proper speeds & settings:
This decides the amount of opening & cleaning that can be achieved by a machine. Highbeater speed & closer beater settings gives better cleaning. But, beater speed & settingdepends upon type of cotton, maturity & trash content. Improper setting, speed results fibredamage, nep generation of cotton.
Type of raw material to be processed : Selection & No. of openers & beaters depends uponthe type of cotton & trash in them Long, finer & immature cottons cannot be subjectedto too many cleaning points, since over treatment will results fibre damage, and neps.
low grade cotton with high trash content will require more beating points.
Factors affecting the lap rejection and theCV % of 1 metre wrapping of lap & causesfor high lap weight variation
BEQ: How the uniformity of the lap is controlled in a scutcher?
Lap rejection % indicate the variability between lap weight and CV % of 1 metre wrapping oflap indicate the variability of weight/metre of with in the lap.
Both these measures are particularly importance in control of yarn count. Both the with inand between lap weight & its regularity are the first steps in the control of count variation.
Factors affecting the both with in & between Lap weight variations and steps to be taken to control the same are:
In sufficient opening of cotton.
Wide variation in tuft size,
Variation in level of cotton in reserve box of hopper feeder
Fluctuations in the feeding rate to the scutcher.
Ineffective working of feed control devices like swing door, BE cell, micro switch, piano feed regualting motion etc.
Irregular & faulty air flow on cage
Unnecessary and frequent adjustment of feed regulating motion.
Uneven mixing of soft waste with cotton
Worn pedal links, knife and cone drum bearing.
Malfunctioning of length measuring motions.
Uncontrolled variations in atmospheric condition in the dept.
Fluctuations in the feeding rate to the scutcher are caused if the different machine's in the sequence are not properly synchronised and if the feed controls like swing door, 1 solenoids, micro switches and relays do not function efficiently.
• The production rate of the blending hopper feeder and other
should be so adjusted that they run for about 80 to 90% of the
running of the scutcher and there should always keep the hopper
with cotton in 3/4 level at all time.
should be so adjusted that they run for about 80 to 90% of the
running of the scutcher and there should always keep the hopper
with cotton in 3/4 level at all time.
The cotton should be fed at uniform rate to the scutcher. The 1 front sheet of the reserve box of the scutcher Hopper feeder is capable of moving forward or backward to increase the volume of the chute, to suit the require weight per yard of lap. So front sheet setting should be corrected according to the lap hank & weight required.
Backsheet in the reserve Box of the scutcher Hopper feeder reciprocates alternatively. This ensures the maximum regularity of the feed to scutcher. So back sheet should function efficiently.
Swing door in the Hopper Feeder, photo electric cell in the reserve box of hopper feeder, step cleaner should be sensitive to
avoid fluctuation in the level of cotton in the reserve bin.
Pedal feed regulating motion should be so set that the cone drum belt operate about the centre of the drum, otherwise full correction is not achieved.
Free movement of the pedal lever and connecting rod must be ensured and care should be taken to see that the movement of the pedal levers is fully transmitted to the belt fork.
Uncontrolled variation in atmospheric conditions can lead to high lap weigh variation. with an average lap out of 16kg, the natural fluctuations in temperature and humidity may account for as much as 1/2 kg variation in lap weight merely due to change in moisture regain. To over come this, Direct reading measuring instruments are recommended in preference to the correction table since the later assume that the lap, as it is produced, is in equilibrium with departmental humidity which is not really true because of 1. the effect of heat developed by the machine and huge velocity of air coming in contact with cotton during its passage through the machine.
Large variations in weight between lap rods can give factious values of full lap weight. So, lap rods must be weighted once in three months' and standardised.
Blow room sequence employing latestbeater suitable for low, medium and finecotton.
BEQ; Suggest a modern blow room fine sutiable for spinning 80s yarn or for processinglow medium cotton or for fine cotton or for processing sea-island cotton Brief functionof each machine in a modern blow room line:
In order to retain adequate mixing three blenders are arranged to feed one single processline. Mono cylinder-open and clean the cotton. Automixer mix the material throughly. Double ERM cleaner, open and clean the cotton. Two way distributor, distribute the cotton fromcleaning line into two automatic scutcher equally.
This modern blow room line is suitable for spinning all range of counts. In the case low grade cotton mixing, (below 40s) all the beaters can be utilised. In case of medium grade cotton mixing (40s - 60s)one ERM cleaner can be bypassed. In the case of fine mixing (above 60s, sea-island cotton) one ERM cleaner and monocyUnder can be bypassed. In the case of staple fibre mixing, the material from the blender is directly fed to scutcher bypassing all the machines in a cleaning line.
Defects in Blow room and causes.
Causes for Nep formation in Blow room;
*Cotton with too high or low moisture.
*Extremely fine cottons with high trash content.
*Reprocessing of laps and mixing of soft waste.
*Rough or blunt blades and bent pins on beaters.
*Narrow settings between the feed roller or pedal and beater.
*Long curved and U-bends in conveyor pipe lines.
inappropriate ratio of fan to beater speed.
*Wider setting between stripping rail and beater blade.
3. Causes for curly cotton:
*Grid bars setting too close to beater.
*Hooked or bent pins on kirschner beater.
*Hooked or bent pins on kirschner beater.
*Too wide a setting of stripping rail.
*Long and bent conveyor ducts with low fan speed.
4. Causes for lap licking :
*Use of too much soft waste in mixing
*Too high fan speed, excessive beating.
*Weigher cotton is damp or departmental humidity is high.
* Sticky nature of material
Remedies: use of roving ends within the lap to act as a layer Separation.
Incorporation of lap felter's.
Use of antistatic spray while processing synthetic.
5. Causes for conical lap:
*Improper functioning of pedals on one side due to pedals being choked with dirt.
*Air entering at one side frcm under the grid bar of beater.
*Defective beater blade at one side.
*Uneven suction at the cages leaving to deposition of more material on one side than another.
*Lap roller racks, calander roller not exerting even pressure across the lap width. *Cages may not be properly levelled.
6. Causes for Soft lap
*Calender pressure inadequate due to wear and tear of weighting mechanism.
Maintenance program - Blow room
Maintenance is a program to keep all the parts of the machine in perfect condition with minimum wear and tear.
Preventive Maintenance in Blow Room;
It means to attend and check the machines regularly and systematically and defects are discovered and remedied before they cause a need for, major repair and before the wear & tear of the machine starts affecting the quality and production,
Parts to be inspected
|
Rating & Action taken Remarks Repaired/replaced
| |
check the condition of
| ||
1
|
spikes on lattice
&lattice tension
|
If the part is defective, write "poor & needs Correction" in the rate & Remark column.
|
2
|
Striking edge of all the beaters
| |
3
|
Feed roller weighting & its setting with beater.
|
The parts that are replaced or repaired will be entered by maintenance incharge.
|
4
|
Position of damper & air current in the cage.
| |
5
|
Sharpness of blade/spike/pins of beater.
|
Importance of maintenance in Blow Room.
|
6
|
Stripping rail setting in beater.
| |
7
|
Function of P.E. cell swing door & other feed control mechanisms.
|
If a serious breakdown occur in Blow
|
8
|
Condition of pedal feed control mechanisms.
|
9
|
Calender Roller bearing &
its weighting.
|
Room, a high proportion
|
of a Mills production will
| ||
10
|
Racks condition & Effectiveness
|
be stopped causing the
|
of brake.
|
subsequent process to be
| |
11
|
Timing and synchronisation of
|
short of material.
|
auto doffing mechanism.
|
This can be avoided to
| |
12
|
Lap length measuring motion.
|
some extent by a thorough
|
13
|
Lap hardening Mechanism.
|
inspection and systematic
|
14
|
Lubrication system
|
Programme of maintenance.
|
15
|
Al1 bearings-condition.
|
which can also helps to
|
16
|
Belt, gear, chain, Robe &
|
reduce the 1ap
|
all driving connection.
|
irregularities and improve
| |
17
|
Motor & its pulley condition.
|
the cleaning efficiency.
|
18
|
Roller vibration/ Eccentricity
| |
19
|
Speed & settings.
| |
20
|
Pan whether chocked with dust,
| |
or not.
| ||
21
|
R.H.% & Temp condition.
| |
22
|
Ratio of fan to beater speed &
| |
Air current.
| ||
23
|
Robe & Bls tension.
| |
24
|
All nuts, Bolts, screws-tightening
| |
25
|
Check for any rough places on
| |
various rollers or calenders
|
Routine Maintenance in Blow Room: It means to attend the machine and maintenance work is carried out as per the maintenance schedule so as to maintain the Machine in perfect condition with minimum wear & tear.
Nature of operation Frequency
1. Dismantling -Checking- thorough
cleaning & resetting of
i) Cage Unit, ii) Lap doffing unit Every month
cleaning & resetting of
i) Cage Unit, ii) Lap doffing unit Every month
iii) Lap measuring Motion
| ||
iv) Lap hardening Mechanism.
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v) Piano feed regulating Motion
| ||
2.
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Cleaning of grid bar
|
Every shift
|
3.
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Removal of droppings from beneath
| |
the grid bar.
|
Twice per Shift
| |
4.
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Straightening of bent pins of
|
Whenever needs
|
kirschner beater and sharpening the
| ||
beater blade.
| ||
5.
|
Polishing of grid bar.
|
6 months
|
6.
|
reversal of beater blade.
|
1 year
|
7.
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Re dressing of beater blade
|
2 year
|
8.
|
Clean inside the cage
|
each shift.
|
9.
|
Applying Black-lead powder inside the
| |
cage
|
periodically
| |
10
|
. General cleaning
|
.15 days
|
11
|
. Lubrication of all the gear wheel
|
Daily & greasing at
|
&. bearing.
|
the time of frame cleaning.
| |
12
|
correct the leakage places in the
| |
entire pneumatic duct line.
|
Every week.
|
Special features of modern beater
BEQ: What are the important features of the modern beater which make them suitable to process different varieties of cotton? Briefly explain them by taking example of a modern beater.
The latest approach is to open and agitate the cotton and remove the micro dust as and when generated before they settle down again.
In all modern beaters (like mono cylinder, Improved porcupine beater, ERM cleaner etc. , the grids can be adjusted individually. The grid can be adopted to handle any degree of impurity and opening in the cotton to be processed by means of the lever provided with scales.
The grid can be adjusted regarding spacing (0 to l2mm) between grid as well as inclination(0 to 30°) , it is thus possible to adjust the amount of waste and its quality to the requirements and the different types of raw material.
Effective control of feed by the electronic feed regulator like P. E cell in the feeding section of the modern beater.
The aero dynamic principle of separation of trash from lint is employed in shirly opener and Airjet cleaner.
Loose beating technique is employed in step cleaner for good opening without any harsh beating. Also Micro dust extraction, improve the processing performance of the O.E. spinning.
The advantage of modern beater is like mono cylinder is that the impurities are separated from cotton without being crushed and this proves favourable during subsequent operations.
Special feature of the axiflo cleaner is that fibre contained in large tufts can not get entangled or lost through the grid. They remain in the machine till they are transformed into small tufts and release their impurities. The position of the adjustable guide plate between the two cylinder decides how long the tufts remain under the influence of the each cylinder.
All modern beaters are simple in construction and efficient unit suitable for all classes of cotton.
Maximum trash extraction.
Adjustable grid bar profile to optimise cleaning efficienty and suitable to process different varities of cotton.
Opening and beating are combined in the same machine for effective cleaning.
Less nep generation.
Less floor space.
Minimum maintenance.
Reduced power consumption.
Good blending action,
Improved yarn strength.
Control system in Blow room
Following control systems are used in the blow room line to control thefeeding and feed the cotton at uniform rate to the scutcher.
1. Photo electric cell is placed in the following places :
i) Reserve feed tower of hopper feeder, step cleaner etc.,
ii) Reserve trunk of automatic scutcher
iii) Laminar trunk of ERM cleaner
iv). Filling trunk of chute feeding system.
Piano feed regulating motion, in the scutcher.
Front sheet position and swing door of hopper feeder.
Pressure switch in feeding trunk of automatic scutcher.
Solenoids, micro switch,limit switch and relays
Already we have seen the working of all the above at various in the previous pages.
.
Advantages of modern Blow room line
Modern Blow Room line or latest developments in the B/R machinery consists
Modern mixing machine ( Automixer, Multimixer, Aeromixer, Latest mixing bale opener etc.,)
Improved opener & Beater ( ERM cleaner, mono cylinder, axiflo cleaner, Airjet cleaner, etc.)
Automatic scutcher.
Automatic lap doffing device.
Salient feature of modern mixer :
1. Perfect and homogeneous blending.
2. Simultaneous mixing by doubling over an extended period of
time is achieved in the case of Aeromixer .
3. In auto mixer, stack mixing principle is adopted and it
permits a controlled accumulation and doubling of different layers of material and uniform thorough blending of material is achieved (ten times greater than conventional mixer). For details of salient features of modern beater, improved openers, automatic scutcher & automatic lap doffing.
Electronic feed regulator motion in Blow Room
Photo electric cell, solenoid, micro switch, limit switch and relays are the electronic elements which are used to control the cotton feed in the blow room line.
Please refer the previous articles for details:
BLOW ROOM CALCULATIONS conversion factors
3. inch = 2.54 cm 1 pound =454 gram 1 ozs = 28.4 gram
1 inch = 25.4 mm 1 pound =7000 grains 1 met = 39.37 inch
10 mm = 1 cm 1 gram 15. 4 grains 1 met = 3.28 feet
10 mm = 1 cm 1 gram 15. 4 grains 1 met = 3.28 feet
36 inch = 1 yard 1 lea =120 yards 1 feet = 12 inch
1 met=100cm 7 lea = 1 hank 1 kg = 2.205 pound
1 met=100cm 7 lea = 1 hank 1 kg = 2.205 pound
1 met =1.09 yards 1 hank=840 yards 1 yards = 91 cm 16 ozs = 1 pound(lbs)
Hank or count means the number of 840 yards length that weigh exactly one pound.
Lap hank Ranges 0.0012, 0.0013.... card sliver hank ranges 0.12,0.13
Yarn count ranges. 2s , ... 10s 20s, 100s.
0.0012 means 0.0012 x 840 yards length in 1 pound of lap. . 0 12 means 0.12 x 840 yards in 1 pound of sliver. 20s means 20 x 840 yards length of yarn in 1 pound of yarn.
* surface speed or delivery of the roller = Pye DN inches/min where pye = constant, 22/7, 3.14
D = diameter of the roller in inches/mi N = Speed of the roller in RpM Surface speed means delivery of the material per minute.
Efficiency = 90 % Speed of Bottom Calender Roller(BCR) = 10 RPM Dia of BCR = 7 inch Lap weight = 16 ozs/yard. Calculate the production in kg/shift of 8 hour Production of blow room in kg/8 hr
Production =10 x3.14 x7 x(1/36)x(1/840)x(1/0.0012)x(1/2. 205) x
60 x 8 x 90/100 = 1188 kg /8 hour
2. Efficiency = 80 % BCR delivery = 7 met/min
wt. of lap = 400 gms/met Production / 8hour=?
Production = Delivery of BCR in inches /min x 1/36 x 1/840 x 1/lap hank x 1/ 2.205 x 60 x 8 x Efficiency /100
Delivery of BCR = 7 met / min
= 7 x 1.09 x (1/840) x (1/0.00147) x (1/2.205) x60 x8x (80/100)
(yard's/min) = 1076 kg / 8 Hr.
= 7 x 1.09 x (1/840) x (1/0.00147) x (1/2.205) x60 x8x (80/100)
(yard's/min) = 1076 kg / 8 Hr.
so, for one rotation of K.w. the delivery of the BCR (lap length) is = 1 x (45/15) x (22/1) x 3.14 x (7/36) = 40 yards (BCR dia is in inches, Divided by 36 to get length in yards)
ii) Change wheel required to produce 42 yards of lap=?
Lap length constant: To find constant, we assume the no of teeth of change wheel is kept as 1.
Constant = 1 x (45/CW) x (22/l)x 3.14 x(7/36) = 605 Change wheel = Constant/laplength required
= 605 / 42 = 14.4 Teeth
iii) Time taken to produce one lap = 5 min.
No of lap produced / 3 hr = 96 lap
Lap weight = 434 grams /metre
Lap length = 42 yards or 38. 38 mts (1000 gram = 1 kg) 1 lap weight = (38.38 x 434) / 1000 = 16.6 kg Production in kg /8 hr or weight of 96 laps = 96 x 16.6 = 1594 kg/8 hour 4. Calculate the speed of 8 inch diameter calender roller of a scutcher, if its delivery is 500 laps of 40 yards in 48 hours the lap hank is 0.0013, calculate the weight of lap. lap length = 40 yards & hank =0.0013