Assembly and connection of flange and pipe 1. The position of the flange screw holes on the pipe should be consistent with the position of the matching equipment or the upper holes of the pipe fittings. The screw holes of the flanges at both ends of the same pipe should be consistent. 2. The sealing surface of the flange should be perpendicular to the center of the pipe. 3. The center of the flange should be on the same line as the center of the pipe. 4. Welding flanges and pipes Welding flanges and pipes are assembled by butt welding, and the welding method and requirements are the same as the welding connection method. 5. Slip-on flange and pipe assembly When the flange is assembled with the pipe, the flange should be inserted into the pipe end first, and a certain distance should be left between the pipe mouth and the flange surface (generally 1.5 times the pipe wall thickness). Spot welding is carried out on either side of the pipe, and then the flange square is used for alignmen…