1, the steel sleeve of rolling mill has two functions: 1) the thin plate prevents the inner ring from collapsing; 2) Prevent the inner ring from being deformed. Because rolling mills often use a lot of tension, and the gap between the drum and the groove of the coiler will lead to the deformation of the steel strip. At least one sleeve or even two sleeves are needed when rolling thin plates in the return compound rolling mill, otherwise, one side of the coil will not be able to roll off the line after the belt breaks.

2. The role of the sleeve in the annealing and pickling line: generally, paper sleeves are used to prevent the collapse, usually on the thin plate. There are few thick plates unless the customer needs them specially.