After the belt is broken, stop immediately, pull out the strip steel in the frame and pull out the middle roll (backup roll) of the work roll to check whether the roll is stuck and damaged, and the roll should be replaced if damaged. And clean up the broken belt debris in the archway. Check the main drive shaft of the rolling mill and the safety pin for breakage, and replace it in time if the breakage is found. The rolling speed of the first coil after changing the rolls should not be too fast, and the surface quality of the strip should be carefully checked.