Determination of the amount and direction of twist by yarn twist tester

Introduction:

Twist is defined as the measure of spiral turns genre to a yarn in order to help the constituent fibres or threads to yelhen according to indicate a standard method for determination of yarn twist.

There are two types of twist direction as

• S-twist
• Z-twist

Theory: By the help of yarn twister direction and amount of twist per-unit length of a yarn can be tester,

T.P.I (single yarn)= Dail Reading/ gauge length

T.P.I (Double yarn) =Dail reading/gauge length

For the machine of our lab twist of single yarn the factor TPI=DailReading/Gauge length is selected main part of the machine to handle is attached. The yarn passed tram the of the bobbin to the fixed jaw of tensioner thought the guide the tensioner is fixed according to the properties of the twist of yarn is fixed jaw the twist of yarn moved by the mention. This is appropriate for single yarn for double yarn the number of turns per unit length is determined by multiplying the counter tending by.

Apparatus:

1. Yarn package
2. Yarn Guide
3. Yarn twist tester 
4. -Rotating jaw
5. Tensioner
6. Counter display-handle 

twist tester

Working procedure:

1. At first we have to draw the yarn hrough the yarn tensioner to yarn Guide.
2. The tensioner is set according to the types of yarn for double tensioner is always 15 mg and for single yarn tension =tex/2
3. The yarn is then set with the fixed jaw and then we have to untwist the yarn with the help of handle.
4. The single yarn untwist retwist meters is used and number of turns per-inch is detwemined tram control reading.there is no need of retwist for double yarn. The number of turns per unit length is then calculating by multiplying the counters reading.
5. For double yarn the handle should be rotated with by moving aneed through the mid point.

Calculation:

Tension: Tex/2 =9 .8

Average T.P.I (single Yarn)=(18.6+17.5+16.6+19.6+18.3)/5=18.1

Average T.P.I (double yarn)= (15+13.2+13.4+14+14)/5=13…

Table 1. table for single yarn count 

obs no	count	tension  =tex/2	Twist direction	Twist  perinch	average T.P.I
1	30	9.84	Z= twist	17,6
2	30	9.84	Z= twist	17.5
3	30	9.84	Z= twist	16.6	18.1
4	30	9.84	Z= twist	19.6
5	30	9.84	Z= twist	18.3

table: 2 for 

obs no	count	tension  =tex/2	Twist direction	Twist  perinch	average T.P.I
1	50	15	s-twist	15
2	50	15	s-twist	13.2
3	50	15	s-twist	13.4	13.5
4	50	15	s-twist	13.8
5	50	15	s-twist	13.8

Result: Number of twist perinch

1. single yarn 18.
2.  double yarn 13.5 

Remarks: Twist direction is very importance for the yarn. stromation , Twist also maintion the Strenght of yarn. It way an improtent angd learnable experiment for us. which will helps usinourjob section.