Disassembly and assembly sequence of non-clogging explosion-proof self-priming sewage pump: 1. Remove the motor or disengage the coupling. 2. Remove the bearing body assembly, check the radial clearance between the impeller and the front ring, and check whether the impeller nut is loose. 3. Remove the impeller nut, pull out the impeller, and check the radial clearance between the impeller and the rear sealing ring. 4. Loosen the set screw of the mechanical seal, pull out the moving ring part of the mechanical seal, check the fit of the end faces of the moving and stationary rings, and check the sealing condition of the "O" ring (or buffer pad). 5. Unscrew the tightening nut of the coupling and pull out the coupling. 6. Remove the bearing end cover, and remove the pump shaft and bearings. 7. Just assemble in the reverse order during installation. Dfin Pump Industry: Professionalism creates the future, quality creates brilliance!