Friction Studies on Caprolan1 Filament Yarn

This paper is presented in three parts. Part I consists of a discussion of the parameters which affect friction and a description of the instrument used for the fric tionitl studies presented in Parts II and III.

Part II is a study of the effect of finish composition and amount of finish on both yarn-to-metal and yarn-to-yarn friction. The results are analyzed from the point of view of the mechanism of operation of the finish film, and a correlation with some of the factors which influence yarn friction has been attempted.

Part III shows the effect of yarn speed, diameter of friction pins, surface contours of pins, and angle of contact with the pin on the friction of 200/16 filament yarn with a commercial-tyhe finish. Here, the results have been explained on the basis of hydro dynamic lubrication between yarn and pins. This concept explains the enormous effect of surface smoothness on friction as well as the effect of pin diameter and of contact angle. Through the concept of hydrodynamic lubrication, it is also shown that the viscosity-temperature relationship of the lubricant is an important factor in shaping the friction-speed curve of the textile yarns.