How to calculate the overall film stress and bending stress at once
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How are the overall membrane stress and bending stress calculated? Are the overall membrane stress and bending stress in a cylinder under internal pressure calculated in the same way as those under external pressure?
For thin-walled containers, only film stress and edge stress need to be considered. Is this a thick-walled container, OP?
Only film stress and edge stress are considered
I’m still very grateful to the original poster for sharing it~
It is a thin-walled vessel, and I need to determine whether it operates under low-temperature and low-stress conditions. Appendix E of GB150.3-2011 defines low-temperature and low-stress conditions as those in which the design temperature of the vessel shell or its pressure-bearing components is below -20°C, but the design stress (the maximum overall membrane stress and bending stress actually experienced by the vessel components under these design conditions) is less than or equal to 1/6 of the yield strength of the steel material at normal temperature, and not greater than 50 Mpa. The design pressure for my current container is -0.1 Mpa, the design temperature is -40°C, the diameter is 3000 mm, the thickness is 8 mm, and it’s made of 16MnDR material. I want to determine whether this represents a condition of low temperature and low stress.
I hope to verify whether it is under low-temperature and low-stress conditions
This post was last edited by zhangjuhua on 2016-5-17 at 22:47. Generally speaking, film stress and bending stress are separate concepts: the cylinder is related to film stress, while bending stress applies to flat covers, etc.; however, for nozzles that are subjected to both torque and internal pressure, both types of stress need to be taken into account. Examples of primary membrane stresses include the circumferential tensile stress in a cylinder, the primary tensile stress in a sphere, etc. A typical example of bending stress is a flat cover, where the internal and external pressures are equal
Put it this way: the stress obtained at the neutral plane of the cylinder represents the total stress. The difference between this stress and the stress calculated based on the inner wall surface is the bending stress