Needle roller, also known as needle cylinder. A metal cylinder with steel needles planted on the surface. It is installed in the drafting zone for controlling and carding fibers. It is used on spun silk and wool spinning roving frame, carded wool spinning frame, spun spinning and shaft spinning frame. The main body of the needle roller is a copper cylinder with small holes drilled on the surface and steel needles are planted in the holes. Both ends of the cylinder are equipped with a flange, the surface of which is slightly higher than the needle tip to protect the needle tip from damage. The main parameters of the needle roller are: bottom diameter, outer diameter, needle width, needle height, needle density, needle angle and needle number. In order to adapt to the processing of different types of fibers, the small carding roller on the rotor spinning machine has the saw teeth replaced with needles, also called needle rollers.