TS 247

TS 247 addresses the determination of yarn twist and is a withdrawn textile standard. Yarn twist describes how fibres are helically arranged around the yarn axis and is one of the key structural characteristics that influences yarn appearance, balance, cohesion, bulk and some handling properties. Because no official scope text is available for this record, the description below explains the general technical background rather than the specific clauses of the standard.

Why twist matters in yarn behaviour

In textile engineering, twist helps bind fibres together and gives yarn its structural integrity. As twist level changes, the yarn’s strength profile, frictional behaviour and processability can also change; excessive twist may lead to undesirable stiffness, shrinkage tendency or a different surface feel. For this reason, twist is not just a numerical value but a parameter that must be interpreted together with the yarn’s intended use.

General principles behind twist determination

In general terms, twist determination is based on measuring the number of turns along a known yarn length and expressing the result per unit length. In practice, this helps quantify the twist in single yarns and understand how component yarns are wrapped around one another in plied yarns. Twist direction is also important, since right-hand and left-hand twist are different structural arrangements that can affect yarn behaviour and compatibility with subsequent processes.

Historically, a standard such as this supports consistent laboratory characterisation of yarns. Accurate twist determination is important for yarn selection, quality comparison, production control and technical consistency between batches.