1. Before assembling the flange, the flange surface, it is nessary to clean the sealing surface.

2. When assembling flat welding flange, the end of the pipe should be inserted into 2/3 of the thickness of the inner diameter of the flange, and then the flange should be spot welded to the pipe. Check and correct the flange position from different directions so that the sealing surface is perpendicular to the center line of the pipe, and then spot weld the second point below it after it is correct.

3. Use a 90° angle ruler to check and correct the flange position from the left and right side, and then spot weld the third and fourth points after passing the test. 

4. To the assembly of a pair of flanges, the bolt holes of the flange to be installed should be aligned with the corresponding bolt holes of the flange that has been fixed, and parallel to the flange that has been fixed, and the deviation should not be 1.5‰ bigger than the outer diameter of the flange, which not over 2mm.

5. When selecting the matching flange of the equipment or valve, pay attention to whether the flange of the original equipment or valve is consistent with the flange connection size of the pipe.

Changsha Xiangjia Metal Materical Co., Ltd. the Steel Pipe Division of ADTO GROUP, is one of the leading manufacturers of steel products in China. We specializes in manufacturing all kinds of steel pipe in various grades and sizes. Years of production experience and manufacturing facilities who have a capacity of 200,000 tons per annual will ensure the good quality and competitive duration of our products.