Identification of the Process of Dynamic Stretching of Threads in Warp-Knitting Technology

• Main Authors: Prążyńska Aleksandra, Mikołajczyk Zbigniew
• Format: Article
• Language: English
• Published: Sciendo 2017-12-01
• Series: Autex Research Journal
• Subjects: rheological models; stretching threads; knitting on warp-knitting machines; elasticity and viscosity coefficient
• Online Access: https://doi.org/10.1515/aut-2016-0039

The publication presents a theoretical study of the susceptibility of rheological models of threads to dynamic stretching in the context of modern, highly efficient textile technologies. Input parameters of the four analyzed models, the Kelvin-Voigt model, the Maxwell model, Standard model 2, and the Zener model, corresponded to the actual values of the coefficients of viscosity, elasticity, kinematic and dynamic loading, and stretching speed for the analyzed polyester silk threads produced in a knitting process, with knitting speeds from 700 to 1,600 courses/min. The research proves that the tested thread models behave differently in the stretching process-the Kelvin-Voigt model is sensitive to both the increases in kinematic loading and viscosity coefficient, Standard model 2 is only susceptible to dynamic stiffness, and the Zener model is significantly sensitive to kinematic loading. All responses of the models increase with the increase in stretching speeds. The obtained results indicate substantial “accuracy tolerance” in setting input parameters while identifying dynamics of the knitting process on warp-knitting machines.