Question 49 (Textile Engineering & Fibre Science)
In a friction spinning process, the diameter of the perforated drum and the average yarn tail diameter resting on the drum are 44 mm and 0.22 mm respectively. The drum and the yarn delivery speed are 5000 rpm and 250 m/min respectively. The actual twist in the yarn with 20% twist efficiency is
| (A) | 400 tpm |
| (B) | 600 tpm |
| (C) | 800 tpm |
| (D) | 1000 tpm |
[Show Answer]
Option C is correct.
Given in the question-
Dia of perforated drum=44mm
Yarn dia=0.22mm
The drum speed=5000 rpm
Yarn delivery speed(FRD)=250 m/min
The actual twist in the yarn with 20% twist efficiency=?
Surface speed of drum=Surface speed of yarn
Rotational speed of yarn(N)=1000000 rpm
Yarn Twist=Rotational speed of yarn(N)/Yarn delivery speed(FRD)
Yarn Twist=1000000/250
Yarn Twist=4000
20% twist eff.
Yarn Twist=4000 x 20/100
Yarn Twist=800 tpm (Ans)