GB1166101A - Apparatus and method for heat treating yarn - Google Patents

Abstract

1,166,101. Heat-setting of filaments. DEERING MILIKEN RESEARCH CORP. 16 Sept., 1966 [20 Sept., 1965], No. 41534/66. Heading B5B. [Also in Division D1] In processing a running length of monofilament or multifilament, thermoplastic, e.g. polyester, polypropylene or nylon, yarn 11, which may have been drawn and/or edge or gear crimped and will shrink in length or be permitted a controlled relaxation when heated, e.g. to develop and/or stabilize the crimp, is overfed by 3-30% through an elongated conduit 12 in the form of a series of compressed coiled turns lined with a low friction material such as polytetrafluoroethylene, nylon or glass, which it enters at a velocity greater than that at which it leaves at 13. Gas is preheated by its flow through a tube, also in the form of a series of coiled turns, located in close proximity to both a circular heating element and the coils of the conduit. The preheated and compressed gas is delivered to the conduit through which it flows in the direction of yarn travel and the yarn is heated thereby to a temperature of 200- 500‹ F. during its passage therethrough over a period of 0À5-10 seconds. The gas may be delivered by an aspirator 10 or a capillary tube as described in Specification 991,771. The aspirator shown in Fig. 9 comprises a portion 91 fitted into a bore 94 in portion 90 so that compressed gas, when it enters through delivery slots 97 around the forward portion 95, is forced through a bore 93 thereby creating a Venturi effect in the vicinity of portion 95 so that suction is created in the area thereof and the yarn is conveyed thereby through bores 100 and 93 and leaves, in twist free condition, through a flared portion 92 in the direction of movement of the gas to the heating apparatus.