中国竞彩网竞彩投注比例 www.ymvpno.com.cn Faults and solutions of common butterfly valves: Possible failures: Sealing surface leakage: 1. The butterfly plate and the sealing surface are clamped with foreign bodies. 2. The closing position of butterfly plate and sealing surface is not in good
Manual valves are the most widely used valves. Their handwheels or handles are designed according to ordinary manpower, taking into account the strength of the sealing surface and the necessary closing force. Therefore
Normally, industrial valves are not tested for strength in service, but after repair, body and bonnet or corrosion damaged body and bonnet should be tested for strength.