The key function of twist is to provide consistency to the yarn i.e. twirl providing potency to the yarn. The consistency arises many times from the twirls which compress the fibers together as the stretching forces are applied and thus forms a friction between adjacent fibers. The laboratory equipment used for determination of twirls of a yarn is known as a Twist Tester.

The key function of twist is to provide consistency to the yarn i.e. twirl providing potency to the yarn. The consistency arises many times from the twirls which compress the fibers together as the stretching forces are applied and thus forms a friction between adjacent fibers. The laboratory equipment used for determination of twirls of a yarn is known as a Twist Tester.