Abstract: To solve the problem of adverse effect on production caused by loosening of exciter of ZKS series linear vibration screen in Yuhua coal preparation plant,analyzed the reason of the problem,presents the method of adding the positioning sub device into the screen,which method is cheaper and simply. The production practice shows that this method effectively reduced the phenomenon of loosening of fasten bolts of bearing base,significantly reduced the maintenance workload of equipment,and ensured normal operation of the plant.