There are currently two process flows for spinning core-spun yarn, taking the processing of polyester-cotton core-spun yarn as an example.

Carding system:

Cotton: cleaning, combing, and combining - coarse yarn - fine yarn (core-spun).

Combing system:

Cotton: clean the cotton, comb one cotton, roll it up, comb it, then roll it together ...

In the actual processing, the selection of the process flow of core-spun yarn depends on the yarn requirements and the yarn count. The general principle is that if you can use coarse carding, you don't need to use fine carding. If you want to use a fine carding system, shorten the process as much as possible to reduce production costs. For example, some manufacturers have good unevenness of combed cotton slivers, and the straightness and parallelism of the fibers are good. After one pass, the slivers can meet the coating requirements. Then, the process can be:

Cotton: clean the cotton, comb it, roll it up, comb it, then roll it together, comb it, then draw it together, coarse yarn, and fine yarn (core-spun).