# Textile Calculation

## Relationship of Twist, Yarn Count and Twist Change Pinion in Jute Spinning

Relationship of Twist, Yarn Count and Twist Change Pinion in Jute Spinning
Engr Avijit Dey
Production Officer
Fabian Group, Chittagong
Mobile: 01836124490
E-mail: avijitdey43@yahoo.com

Twist per inch of yarn varies from count to count of yarn.

Basically, the lighter or finer the yarn, yarn count numbers small, the more the twist per inch and vice versa. Twist for yarns having the small degree of twist varies inversely as to the square root of their count.

(a) More Twist Per Inch on the yarn---small yarn count
(b) Less Twist Per Inch on the yarn--- big yarn count

Example: 01
If 9lbs per spyndle hessian weft yarn has 3.8 TPI, what will be the TPI for 10lbs/spyndle hessian weft yarn?. Both the yarns having the same degree of twist.

Let T be the twist per inch for 10 lbs/spyndle yarn.

√9        T
Then, …… = …………
√10     3.8

Or, √10 × T= √9 × 3.8

Or, 3.162 × T = 3 × 3.8

3 X 3.8
Then, T = ……………..
3.162

= 3.6 (ANS)

(a) More Twist Per Inch on the yarn---- small TCP
(
b) Less Twist Per Inch on the yarn---- big TCP

From (a) and (b) above, it is observed that twist has inverse relation both with the square root of yarn count and TCP. Therefore, square roots of yarn count has direct relation with TCP.

Example: 02
48 teeth TCP for 9 lbs per spyndle hessian weft yarn: what TCP for 10 lbs per spyndle hessian weft yarn? Both the yarn having the same degree of twist.

Let P be the TCP for 10lbs yarn,

48        √9
Then, ……. = ………….
P       √10

Or, P × √9 = 48 × √10

Or, P × 3 = 48 × 3.162

48 × 3.162
Then, P = …………
3

= 50.572, say, 51 teeth (ANS)