scope:

This International Standard specifies a method for the determination of twist in textile glass continuous filament yarns and staple fibre yarns. In the case of staple fibre yarns, the results obtained should be regarded as indicative only. This International Standard does not take apply to rovings. Determination of the twist must take into account the fact that the run-out system may have an influence on the results. When the yarn is run out tangentially, this system does not induce any change in the twist level that was given by the twist frame. On the other hand, if the yarn is run out overhead, the measured twist level is modified, depending first on the winding direction, secondly on the length of wound wrap. This change in relative value is small when twist is high and wrap length is long.