Optimisation of the Knitting Process on Warp-Knitting Machines in the Aspect of the Properties of Modified Threads and the Vibration Frequency of the Feeding System!

Department of Knitting Technology Technical University of Lodz, ul. Żromskiego 116, 90-924 Łodź, Poland E-mail: zbigniew.mikolajczyk@p.lodz.pl Abstract Important factors determining the behaviour of the knitting process on warp knitting machines are the mechanical properties of warp threads. This is caused by the variety of the properties of threads, ranging from “rigid” threads, such as steel, aramid, basalt, and glass threads intended for technical products to “elastic” threads in the form of elastomers, intended for linen and clothing products. Great differences in the rigidity and viscosity of threads significantly influence the parameters of the knitting process. As a result of the simulations performed, it was noted that there is a correlation between the elasticity, the damping of the feeding system, the dynamic loads of threads, the vibration frequency of the feeding system and the rheological parameters of threads. In conclusion, with an increase in the rigidity of threads, the elasticity of the system and frequency of vibrations in the system increase as well. The above-mentioned parameters of the process that are dependent on the coefficient of thread damping change in an inversely proportional manner.