A New Concept in Cooler Design for False-Twist Texturing Systems

In false twist texturing, yarns are bulked by the sequential operations of twisting, heating, and cooling. The current speed for false twist texturing is limited by the early onset of threadline instability. It is well known that there is a potential to increase speeds by reducing the length of each element of the process. This paper describes the develop ment of a short-length water cooler that operates by direct contact between water and yarn. The important design parameters are identified and optimized, and the predicted perfor mance is in agreement with simple transient heat transfer theory. Trials have shown that commercially acceptable 167 decitex yarns can be produced with continuous running at 1000 m/min and with a potential speed of 1700 m/min or more.