Calculation of Loom Timing
Dwell period:
Dwell is the stationary period when the heald frames do not change their position and the shade remains open to allow the passage of the shuttle from one shuttle box to the other.
Timing of loom:
The timing in loom cycle generally refers to the position of sley. Timings are described in relation the angular position of the crank shaft from the reed derive their motion.
Dwell is the stationary period when the heald frames do not change their position and the shade remains open to allow the passage of the shuttle from one shuttle box to the other.
Timing of loom:
The timing in loom cycle generally refers to the position of sley. Timings are described in relation the angular position of the crank shaft from the reed derive their motion.
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Loom timing |
PPM = Pick Per Minute
PPI = Pick Per Inch
RPM = Rotation Per Minute
Problem-1:
Find out the PPM of the loom from the loom from the following information:-
- Motor rpm = 950
- Motor pulley dia = 3″
- M/C pulley dia = 8″
- No of tappet = 4
- Counter shaft = 75
- Crank shaft wheel = 74 T (2:03sp)
PPM
………………… = Counter shaft
No of tappet
=> PPM = Counter shaft x No of tappet
=> PPM = 75 x 4 = 300 (ANS)
Problem-2:
Find the production/hour of a loom in which the auxiliary shaft is running at 50 rpm, and there are 4 picks to the round, assume PPI = 40 (3:03sp)
Solution:
PPM
………………… = Counter shaft
No of tappet
=> PPM = Auxiliary or counter x 4
=> PPM = 50 x 4
=>PPM = 200
PPM
Production of Loom = ......................
PPI
200 x 60
= ……………….. yds/hr
40 x 36
= 8.3 yds/hr (ANS)
Problem-3:
Solution:
PPM
………………… = Counter shaft
No of tappet
=> PPM = Auxiliary or counter x 4
=> PPM = 50 x 4
=>PPM = 200
PPM
Production of Loom = ......................
PPI
200 x 60
= ……………….. yds/hr
40 x 36
= 8.3 yds/hr (ANS)
Problem-3:
Find RPM of bottom shaft, Crank shaft and PPM from data-
PPM
………………… = Counter shaft
No of tappet
=> PPM = Auxiliary or counter x 4
=> PPM = 75 x 4
=> PPM = 300 (ANS)
Crank shaft = 300 (ANS)
300
Bottom Shaft = ………….. = 150 (ANS)
2
- No. of teeth in crank shaft = 48T
- RPM of counter shaft = 75
- Picks to the round = 4
PPM
………………… = Counter shaft
No of tappet
=> PPM = Auxiliary or counter x 4
=> PPM = 75 x 4
=> PPM = 300 (ANS)
Crank shaft = 300 (ANS)
300
Bottom Shaft = ………….. = 150 (ANS)
2