outlet to inlet yarn tensions proper selection of outlet angle u03b2 is also important but does not change the above conclusions this example uses process and apparatus embodiments disclosed in fig3 and described previously to treat undrawn feed yarn spun polyhexamethylene adipamide yarn with seven filaments and a total denier of 53 is drawn and false twisted as described yarn speed on draw roll 76 is 850 yd min to provide a draw ratio of 2 619 hot plate 66 is 20 inches long and heated to 230 u00b0 c surface temperature yarn 60 contacts hot plate 66 only along 10 inches of its length inlet yarn angle u03b1 is 90 u00b0 and outlet angle u03b2 is 69 u00b0 rotational velocity of bushings 70 and 72 is 30 000 rpm windup of drawn and textured yarn 80 is at a yarn speed 5 3 less than the draw roll velocity bushing friction is indirectly measured in terms of hardness in degrees of international rubber hardness using a shore type a durometer astm test no d1415 56t the harder the bushing the lower is the yarn to bushing friction in test 2a the inlet bushing has a shore a hardness of 80 u00b0 and the outlet bushing a shore a hardness of 97 u00b0 in comparison test 2b both bushings have a shore a hardness of 80 u00b0 yarn tension t 1 immediately prior to reaching bushing 70 and yarn tension t 2 immediately after leaving bushing 72 are measured any customary yarn tensiometer suffices a rothschild electronic tensiometer is employed critical processing parameters are given in table iii and yarn properties obtained are shown in table iv it is seen that use of a lower friction.