In order to ensure the efficient operation of the pump, it is necessary to adjust the clearance between the impeller and the front guard plate in time. When adjusting the clearance between the impeller, stop the pump first, loosen the bolts that compress the bearing box, loosen the adjusting nuts, and move the bearing components forward. At the same time, rotate the shaft by hand according to the rotation direction of the pump until the impeller and the front guard plate are abraded. Then, use the adjusting bolts to move the rotor backward, and record the front and rear moving room. The clearance shall be evenly distributed between the front and rear guard plates of the impeller until the clearance between the impeller and the front guard plate and the rear guard plate is equal, and the two dust discs shall be tightly adjusted and fastened on the shaft. After adjustment, before starting again, it is necessary to check whether the impeller can rotate normally and whether the compression bolt of bearing assembly can be tightened, and then start the pump.