Processing parameters optimization of draw frame for rotor spun yarn strength using gene expression programming (GEP)

Breaking strength is one of the most important mechanical property of a yarn as it is the main parameter for quality control. This property depends on many different factors namely, raw material factors, process variables and machine parameters. Since, there is a high degree of interaction between yarn properties and influencing factors therefore, optimal processing conditions can not be determined easily. This article proposes prediction approach for the determination of the breaking strength of the yarn using gene expression programming (GEP) and optimization technique using MATLAB software. A nonlinear mathematical function was derived on the basis of draw frame variables that were distance between back and middle rolls, delivery speed and break draft by GEP. Afterward, optimal conditions were found in such a way that breaking strength to be maximized. Study showed that, optimal processing parameters including distance between back and middle rolls, break draft and delivery speed were respectively, 10.70 mm, 1.90 and 541.51 m/min (687.95 or 721.32 based on the optimization procedure).