How to determine whether the equipment flanges meet the requirements under hydrostatic testing?
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How to determine whether the equipment flanges meet the requirements under hydrostatic testing? (For designing the tooling) does it mean changing the allowable stresses for the flange, cylinder, and bolts to 0.9 times the yield limit for the calculations?
The allowable stress for ordinary flanges is generally quite conservative, so no verification is required during hydrostatic testing. If calculating, verify using the parameters of the hydrostatic test
The Whartons method is used for the calculation of GB150 flanges; this approach is based on purely elastic analysis, and the nominal stresses calculated using it correspond to higher allowable stresses. Since the allowable stress of the flange material itself includes a safety factor, a hydrostatic test is not necessary for the flange.
The calculation method for flanges according to the standards differs from the PN and T values of standard flanges currently in use in China; as long as the PN and T values of the flange chosen meet your requirements, no calculation is necessary
This post was last edited by GQZHU on 2010-7-7 at 10:48. Do the parameters for a hydrostatic test refer to the test pressure being the design pressure, the temperature being room temperature, and the allowable stress being the allowable stress at room temperature? I don’t think this is appropriate. After all, a hydrostatic test is only a short-term measure
I hope some friend can help answer it
I think it is still necessary to carry out calculations. Sometimes, clients may request a value that is higher than 1.25 times the standard value; in such cases, extra caution is required. The calculations can be done using the design method for flanges with a size of 150, with only the allowable stress value needing to be adjusted – it should be based on 0.9 times the yield strength for verification purposes
It seems no one can explain it clearly! ! !