Working Principle of Crimping in Warp Knitting Machines and Related Equipment

Working Principle of Crimping in Warp Knitting Machines and Related Equipment

1.Basic Principles of Crimping  

   Permanent wave deformation of fibers/yarns is achieved throughmechanical force orthermal energy:  

   -Mechanical Crimping: Uses gears, rollers, or textured crimping rollers to apply pressure on fibers  

   -Heat-Setting Crimping: Heats synthetic fibers (typically 180-220°C) to soften and set the crimp  

   -Composite Crimping: Combines mechanical pressure and heating simultaneously (e.g., polyester processing)  

2.Crimping Process in Warp Knitting Machines  

   Taking crimped yarn application in warp knitting as an example:  

  (1) Crimped Yarn Preparation  

   -Feeding Stage: Straight yarn enters the crimping device via a tension controller  

   -Pressure Deformation:  

     - Yarn is pressed between a pair ofgrooved crimping rollers  

     - Roller pressure reaches 5-20N/mm² to form regular waveforms  

   -Heat-Setting: The crimped shape is fixed using a hot air chamber (for synthetic fibers)  

  (2) Integrated Crimping in Warp Knitting Machines  

   -Online Crimping System:  

     - Mini crimping units are directly installed at the yarn feeding end  

     - Real-time adjustment of crimp degree (typical wavelength: 0.3-1.2mm; wave height: 0.1-0.5mm)  

   -Process Control:  

     - Crimping frequency synchronizes with machine speed (e.g., 1 crimp per needle)  

     - Pressure/temperature parameters are adjusted via PLC