Abstract: The article carried out a study of the relationship between cylinder speed of carding machine and immature fiber content. The study result shows that the speed of cylinder has evident effect on immature fiber content. First, the immature fiber content is gradually reducing in both carding and first drawing steps and it didn’t pick up along with the increase of cylinder speed; but in the second drawing step, immature fiber content is increasing along with the increase of cylinder speed.

Key words: carding machine; first drawing; second drawing; cylinder speed; immature fiber content