Knitting - technological compulsions on quality of cotton yarn

Table 1 Variation in yarn to metal friction coefficient

Sr. no.	Sample code	Mean coeff. of friction	CV % of Mean	Overall CV %
1	A16K	0.141	2.29	7.14
2	B18C	0.156	6.41	11.42
3	C20K	0.142	7.86	12.68
4	D20C	0.138	2.49	12.09
5	E20K	0.136	4.05	5.82
6	F20C	0.139	6.23	7.73
7	G20C	0.140	4.31	12.04
8	H24K	0.133	3.24	5.43
9	I24C	0.136	3.17	21.06
10	J24C	0.140	3.02	6.05
11	K26C	0.140	2.87	7.22
12	L30C	0.135	1.58	8.21
13	M30C	0.133	7.07	12.10
14	N30C	0.145	6.29	7.63
15	O30C	0.138	5.35	24.66
16	P40C	0.141	8.36	15.15
17	Q40C	0.110	5.71	23.98
18	R40C	0.138	4.66	23.90
19	S30W	0.321	0.62	1.34

K = carded yarn, C = combed yarn W = warp yarn

However, the point to be noted here is the importance of this property and the factors that can influence this rigidity in hosiery yarns. Torsional properties of spun yarns depend on torsional, tensile and bending properties of staple fibers [15], twist in yarn, thickness of yarn, compactness and strain energy stored in yarn, etc. All these parameters can vary from yarn to yarn, though their general properties are more or less same, due to changes in spinning condition and yarn conditioning after spinning. The values in table 2 and 3 show the relation between few crucial yarn properties and knitting tension (cam force) and loop dimension [13].

Table 2 Correlation between yarn properties and cam force

Yarn properties	Rib	Half cardigan	Interlock
Relative rigidity	0.78	0.90	0.73
Thickness	0.76	0.93	0.77
Mean Torsional rigidity	0.81	0.92	0.85
Flexural rigidity	0.74	0.80	0.82
Yarn Coeff. of friction	0.34	0.45	0.01
Multiple R	0.86	0.97	0.91
Multiple R-Sq.adj.	0.70	0.92	0.80

Note: Due to narrow distribution of yarn friction coeff. in samples the correlation is low