Abstract: In order to solve the problems of broken tooth plate is easy to loose and transom bolt installation space limited in Xiaokang colliery coal preparation plant,the crushing roller and transom bolt is modified. A projection with 30 mm height and 25 mm width was added in the central of the wheel and tooth plate junction surface,and on the corresponding tooth plate connection opened a groove with 25 mm depth and 30 mm width,which through the clearance fit created a tight connection. This connection measure effectively reduced the bolt looseness phenomenon,and fastening and installation a new type bolt not limited by the space,significantly shortened the fastening time of square tail bolt.