Product Name: Round with pressure as the mirror hole Series: sanitary manhole Series Place of Origin: Wenzhou: sanitary manhole should have a set out of the tubing near the right-hand side, and try to make the hole on the tank room closed doors, so that the people in and out, repair tanks and ventilation takeover. Processing flange and cover seals, pay special attention to protection in the construction. Seal 3mm thick asbestos rubber gasket, does not allow the fracture. Manhole cover is installed on the bolts diagonally with force, to prevent manhole cover deformation. Since the manhole is installed on the lowest level of the tank body ring, anti-leakage is particularly important. Two of the Flange must ensure that its flatness, Gone with the Wind twist phenomenon. Reinforcing plate and flange should be on a single piece of steel cut without stitching. :