DRAW RATIO

Elastomeric yarn has high stretch and recovery properties, which are affected by tension on the yarn during fabric production and yarn covering.

​

Lawson Hemphill Constant Tension Transport for Elastomeric Yarns, CTT-E is a dynamic quality control test instrument, specifically designed for the elastomeric yarn market in mind.

 

Conventional static tensile testers can only measure small test lengths at slower test speeds. This does not reflect the process conditions that the elastomeric yarns will be facing. The CTT-E provides a dynamic test platform to measure the yarn properties and performance factors such as Draw Ratio, Elongation %, Unwinding Tension, Hot Air Shrinkage as the yarn is moving at test speeds from 10m/min up to 1000m/min.

 

This speed range along with the sensitive tension heads provides true information regarding yarn behavior during fabric formation, air or mechanical covering and comfort level of the end product.

 

The CTT-E can be equipped with optional Elastomeric Yarn Feeder to measure the Unwinding tension under conditions that are very close to zero draft.