Questions about flanges and valves
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A few days ago we bought a gate valve, and when it arrived and was installed, the dimensions didn’t match. It should be a standard question. May I ask: what standard do you use? I hope my friends can help me. If there is a standard, please send it to me; I would be extremely grateful. My QQ email address is 526359136@qq.com. Thank you!
Could you provide some parameters? API 6A products?
I’m not sure what type of business your company is in. The standards for flanges on valves are generally JB79.1, GB9113, and HG20592. As for the issue of inability to connect, I’m not aware of the diameter of your valve; if the pressure rating and diameter are the same, connection should be possible. The center distances for flanges according to JB79.1/GB9113/HG20592 standards are basically the same. In fact, China’s flange standards are all based on ASME and DIN standards. The HG20592 standard specifies that the outer diameter and thickness of flanges are generally larger than those specified by JB79.1 and GB9113. HG20592 is divided into two categories: one is the American series, which follows ASME B16.5 standards, and the other is the European series, which follows DIN standards. If the pressure ratings are the same, then the same bolt hole center distances will allow for connection. However, if the valve operates at a pressure of 1.6 MPa while the corresponding flange is rated for 150 LB, different bolt hole center distances will prevent connection. Under different standards, flange connections under the same pressure can result in varying outer diameters of the flanges; it should not lead to differences in center distance, though I’m not entirely sure about this. After all, there are too many flange standards in China, and it’s impossible to compare each one for every diameter. However, the outer diameters and thicknesses according to the HG standard are generally larger than those of other standards.
Explain the specific reasons why it can’t be installed
You can actually measure the dimensions of the flange; petrochemical companies generally use HG/T 20615, HG/T20592, and SH3406