Mechanics of Texturing Thermoplastic Yarns Part X: Effect of Frictional Snubbing on Pseudo False Twisting During Set Texturing

Abstract

The occurrence of temporary twist in a torque stretch yarn passing through the resetting heater is confirmed. Separate measurements are made of threadline torque development during reheating of the yarn and of the corresponding twist required to relieve said torque. These data are used in a graphical explanation of the uptwist/ untwist phenomenon that occurs in the resetting heater and is termed pseudo false twisting because of the absence of a mechanical device.

The presence of a snub pin in the threadline downstream of the second heater modifies the yarn torque level across the resetting zone, reducing uptwist levels and suppressing residual torque of the set textured yarn. A graphical explanation of the pin effect is also provided.

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References

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