In the textile spinning process, Ribbon Lap Machine plays an important role in preparing uniform laps for the comber. It is responsible for converting multiple sliver laps into a uniform, continuous, and compact ribbon lap. This lap is then fed to the comber machine, where high-quality combed sliver is produced. Accurate production calculation of the ribbon lap machine is vital for efficient mill operations, resource planning, and quality control.
General Gearing Diagram of Ribbon Lap Machine
The drive from the motor pulley is given to the loose and fast pulleys on the machine shaft. This shaft drives the front roller, which in turn, drives a set of drafting rollers. The drive to the creel roller holding the feed laps is given from the back roller through a chain drive.
The machine shaft also drives the table calender roller and weighted C.R. The drive to shell rollers (on which the ribbon lap is formed) is given from weighted calender rollers.
Production Calculation of Ribbon Lap Machine
Speeds of Ribbon Lap Machine:
………………………….1000 x 3.625
Machine Shaft = ————————————–
……………………………..15.75
= 230.15 r.p.m.
……………………….230.15 x 15 x 16 x 20
Shell Rollers = —————————————–
……………………………..35 x 21 x 45
= 33.40 r.p.m.
……………………………230.15 x 15 x 16
Weighted C.R. = ——————————
………………………………..35 x 21
= 75.15 r.p.m.
……………………230.15 x 36 x 20
Table C.R. = ——————————
………………………..61 x 20
……………………….230.15 x 71
Front Roller = ————————-
……………………………56
= 291.79 r.p.m.
………………………291.79 x 26 x 38
Back Roller = ————————————-
…………………………..84 x 70
= 49.02 r.p.m.
……………………….49.02 x 36
Third Roller = ————————–
…………………………..30
= 58.83 r.p.m.
…………………………58.83 x 34 x 50
Second Roller = —————————-
…………………………….40 x 18
= 138.90 r.p.m.
……………………49.02 x 30 x 19 x 60
Lap Roller = ———————————
…………………………61 x 17 x 56
= 28.86 r.p.m.
Surface Speeds of Ribbon Lap Machine:
…………………………..75.15 x Π x 5
Weighted C.R. = ————————- x 0.3048 [Note: 1 ft/min = 0.3048 m/min]
………………………………..12
= 29.98 m/min
…………………….135.82 x Π x 11
Table C.R. = ———————— x 0.3048
………………………….4 x 12
= 29.80 m/min
………………………291.79 x Π x 5
Front Roller = ——————————- x 0.3048
……………………………4 x 12
= 29.10 m/min
…………………………138.90 x Π x 1
Second Roller = —————————— x 0.3048
………………………………..12
= 11.08 m/min
……………………….58.83 x Π x 5
Third Roller = —————————– x 0.3048
………………………….4 x 12
= 5.86 m/min
………………………49.02 x Π x 5
Back Roller = ————————— x 0.3048
………………………….4 x 12
= 4.89 m/min
…………………….28.86 x Π x 17
Lap Roller = ————————— x .3048
…………………………8 x 12
= 4.89 m/min
Drafts Between
1) Shell Roller and Weighted C.R. = 30.98 / 29.98 = 1.03
2) Weighted C.R. and Table C.R. = 29.98 / 29.80 = 1.006
3) Table C.R. and F.R. = 29.80 / 29.10 = 1.02
4) F.R. and S.R. = 29.10 / 11.08 = 2.62
5) S.R. and T.R. = 11.08 / 5.86 = 1.89
6) T.R. and B.R. = 5.86 / 4.89 = 1.19
7) B.R. and Creeper Roller = 4.89 / 4.89 = 1.0
8) Draw-Box Draft = 29.10 / 4.89 = 5.95
9) Total Draft = 30.98 / 4.89 = 6.33
10) Draft Constant = Total Draft × C. P.
= 6.33 × 38 = 240.54
For varying drafts, the following equation may be used when the value of the change pinion (C.P.) is required to be changed. This is done for obtaining the desired weight per unit length of the lap.
Draft = (Draft Constant) / (Change Pinion)
[Note: The value of the draft to be put also depends upon the hank of the material fed]
Production Calculation:
The production of the machine for a lap weight of 500 grains/yd or 35 g/m is as follows:
…………………….30.98 x 60 x 8 x 35
Production = ————————————
……………………………..1000
= 520.46 kg/shift
Here again, the production is affected due to the losses in efficiency. These are usually owing to machine downtime for maintenance and repairs, changes in the mixing and package changing time for the feed and delivered laps. The actual production time, therefore, will be less by about 8–10%.
Conclusion
The Ribbon Lap Machine is a crucial preparatory machine in combed yarn production. Accurate calculation of its production ensures efficient planning, helps control production targets, and optimizes resource usage.
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Founder & Editor of Textile Learner. He is a Textile Consultant, Blogger & Entrepreneur. Mr. Kiron is working as a textile consultant in several local and international companies. He is also a contributor of Wikipedia.
