Study On The Cotton Yarn Process Of Quadratic General Rotary Unitized Design

This paper studies the configuration and the process of drafting device of a spinningmachine and analyzes the process conditions of draft in domestic cotton spinning equipment.For the problem of the transmission point of floating fiber distribution instability, improvingthe drafting device in cotton spinning back drafting zone, increasing the apron draftingdevice, and improving the distribution of additional fiction field which in the back draftingzone. The improved technology of apron drafting device at back drafting zone is reflected inthe following points: it’s easy to install and clean, and has a tight structure; with adjustablebottom pin location and a convenient adjustment of process parameters; it can regulate aprontension, achieve control of apron elasticity, and obtain a high degree of smoothness. Thispaper uses the quadratic general rotary unitized design, which can establishes a regressionmodel about yarn quality indicators and3parameters that including: drafting ratio at backzone is1.762, back roller gauge is29mm, and front spacer is2mm; which can also obtain theoptimum technological conditions. To test the optimize process parameters, the identicaldegree that between yarn evenness CV%, thin places, thick places, neps and theoreticalprediction are respectively reached98%,100%,90%,88%.The results show that drafting ratio at back zone is an important parameter, whichaffects yarn evenness CV%, thin places and thick places using main effects. the aprondrafting device at back drafting zone, which effectively improves the drafting ratio at backzone and yarn quality: Drafting ratio at back zone from1.175to1.732, the yarn evennessCV%, thick places, neps index of CJ60S have reached the2007Uster5%level, and the thinindex has reached the2007Uster25%level.