Modelling of the carding process for spunlace nonwovens with particular regard to selected mechanical parameters in a double-drum card. Part 2: Modelling of delay times in the longitudinal mixing process

The production of Spunlace nonwoven fabric is a complex process and includes, among other things, several important stages, such as carding, needling and drying. One of the most important stages is the carding process, which has a significant impact on the shaping of the physico-mechanical and qualitative characteristics of the nonwoven fabric. The article presents the modelling of the carding process in a two-drum system. A mathematical model, determining the expected number of drum and carding card cycles was proposed. Based on this model, delays were determined, due to longitudinal shifts of fibre in the carding process. Numerical simulations have been made and discussed in relation to fibre collection factors, at different production speeds and the number of carding rollers in the worker-stripper system.