Inspection before using flexible waterproof casing.

Check the rubber seal of the waterproof sleeve before use, there shall be no cracking, misalignment, mismatch and other phenomena. The surface in contact with the rubber ring should be clean, and the rubber ring on the pipe through the wall should be straight and should not be deformed.
 
Necessary pipe supports and piers should be set on the walls of nearby buildings to ensure the uniformity of circumferential clearance when installing the through-wall pipe. The casing flange is concentric with the flange cover shaft, and the rubber sealing ring has good sealing performance and service life. Bolt fasteners should be set on the side of easy manual operation, bolts should be uniform, symmetrical, low tightening.
 
When making flexible waterproof casing, the thickness of the wing ring and flexible waterproof casing should meet the specification requirements. Both sides of the wing ring of flexible waterproof casing should be welded on both sides, the weld should be full, flat and smooth, without slag, bubbles and cracks. Weld slag should be cleaned up after welding, coated with antirust paint more than twice. Installation, the two ends of the flexible waterproof casing should be fixed with steel clamping, and shall not be flexed.