Yarn Twist
According to Morton,
“When a strand is twisted the component fibers tend to take on a spiral
formation, the geometric perfection of which depends on their original
formation.”
According to Skinkle,
“Twist is the measure of the spiral turns given to a yarn in order to held the
constituent fibres or threads or threads together.”
According to WIRA,
“Twist may be defined as the rotation about the yarn axis of any line
drawn on the yarn which was originally i.e. before twisting parallel to the
yarn axis”.
According to Textile
Institute, “Twist is the spiral disposition of the components of a thread
which is usually the result of relative rotation of the two ends”.
Twist direction
The direction of twist is
indicated the use of the letters ‘S’ and ‘Z’ in accordance with the following
convention:
(a) S-twist: A single
yarn has S twist when it is held in the vertical position, the fibres inclined
to the axis of the yarn conform in direction of slop to the central portion of
the letter S.
(b) Z-twist: The
yarn has Z-twist if the fibres inclined to the axis of the yarn conform in
direction of slope to the central portion of the letter Z.
Twist Tester, to determine yarn twist in single or plied yarns, quadrant type with auto stop & reverse for conventional or untwist/re-twist methods. Twist tester offers adjustable test length up to 500mm/20 inches for S & Z twist yarns, and inching function helps an operator to get an esteemed twist quickly.
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