T02B Ply Twist, Double Twist

AWTA TEST CODE

:

T02B

OTHER NAMES

:

PLY TWIST, DOUBLING TWIST

TEST METHODS

:

AS 2001.2.14
ASTM D1423
BS-F 2864
DEF(AUST)5037-A8
ISO 2061
IWTO DRAFTTM-25

IMAGE

:

Semi-Automatic Twist Measuring Apparatus

APPLICATION

:

This method is applicable to folded yarns capable of being untwisted as well as to folded yarns able to be removed from fabrics. The method is NOT applicable to core-spun, open-end spun and air-vortex yarns.

PRINCIPLE

:

The twist in a known length of yarn is removed by rotating one end of the specimen until the components of the yarn are straight and parallel. The number of turns required to remove the twist is reported in turns per unit length of the twisted yarn.

SAMPLES REQUIRED FOR TESTING

:

Yarn from packages

1. Bulk sample

Number of cases in shipment or lot

Minimum number of cases to be selected at random

3 or less

1

4 to 10

2

11 to 30

3

31 to 75

4

76 or more

5

2. 10 yarn packages shall be selected at random from the bulk sample.

3. Smaller samples can be tested on request, but the precision of the result will be affected.

Yarn from fabrics

A minimum area of 1.5m2 of fabric.

INTERPRETATION

:

Test results should be within ±5 percent of the nominal twist which is usually stated in the material specification.

SERVICE TARGET

:

6 days.

COST

:

See Fee List.