Hydraulic test pressure and time for pressure vessels
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This post was last edited by dodoren on 2021-4-28 at 12:57. We have several devices with a design pressure of around 220 BAR; the test pressure is 1.5 times the design pressure, and the required testing time is 8 hours (in accordance with ASME standards). I have a few questions: 1. How is the hydrostatic test verified? 2. Since it is a high-pressure device, we conducted a finite element analysis on the areas of the pipe subjected to secondary stresses. The value of these secondary stresses is close to three times the allowable stress of the material. Is this acceptable? What is the basis for this? 3. Will an 8-hour hydrostatic test have an impact on the equipment? Will it cause excessive deformation? 4. Is it necessary to check secondary stresses during hydrostatic testing? 5. Under what circumstances are secondary stresses generally considered? I appreciate your guidance.
I’d like to ask more questions. Does no one know?
Can stress verification be carried out according to conditions with reference to JB4732, so that secondary stress verification may not be required for certain parts if they meet specific conditions? The determination of primary stress and secondary stress is available in 4732, but this is a domestic standard. The water pressure duration takes into account one issue: short-term overpressure is not a major problem; the national standard specifies a half-hour duration for water pressure, but this short period is not defined specifically. For the secondary stress check under water pressure, see the previous reply.
The domestic qualification standard is determined by using 1.5 times or 3 times the allowable stress