A question about the standards of U-PVC pipes and fittings
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This post was last edited by xyfeng007 on 2020-6-4 13:34. I had a doubt when I was looking at the standards recently. I hope fellow friends can help me solve my doubts. Thank you very much. Why does GBT 4219.1-2008 pipe standard require that the minimum strength MRS of raw materials is not less than 5 MPa?: However, the GBT 4219.2-2015 pipe fittings standard requires that the minimum strength MRS of raw materials is not less than 25 MPa. Why are the material requirements for UPVC used to make pipes and UPVC used to make pipe fittings so different? What is the reason for this request?
The local stress of pipe fittings is greater than that of pipes, so the allowable stress is also greater
The pressure and force duration experienced by pipe fittings and pipes are different. When the pipe is under pressure, the liquid or gas phase will flow along the pipe, while the pipe fittings continue to bear pressure, and as the pump starts and stops, the pressure on the pipe fittings is constantly changing. Therefore, the minimum design pressure values are relatively different.