1.quality WN Flange products Before assembling flanges, the flange surface, especially the sealing surface, must be cleaned.

　　2. When assembling a flat welded flange, the pipe end should be inserted into 2≤3 of the thickness of the inner diameter of the flange, and then the flange and the pipe should be spot welded. If it is a horizontal pipe, the flange should be spot welded from above, and then the flange position should be checked and corrected from different directions with a 90° angle ruler, so that the sealing surface is perpendicular to the centerline of the pipe, and then the second under spot welding point is correct.

　　3.quality WN Flange products Use a 90° angle ruler to check and correct the flange position from the left and right directions, and complete the spot welding and fixing of the flange after passing the third and fourth spot welding.

　　4. As far as the assembly of flange pairs is concerned, the bolt holes of the mounting flange should be aligned with the corresponding bolt holes of the fixed flange and parallel to the fixed flange, and the deviation should not be less than 1.5% of the outer diameter of each thousand flanges. And not more than 2mm.

　　5. When selecting the matching flanges of quality WN Flange products equipment or valve parts, attention should be paid to whether the flanges of the original equipment or valve parts are consistent with the flange connection size used in the pipeline.