How to select the allowable stress for boiler components?
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I would like to ask gently: Some current flow meter manufacturers use SA335P91 as the material for the flow meter housings. Since the allowable stress for this material cannot be found, they use the allowable stress for the 10Cr9Mo1VNbN (GB5310) material as specified in GB16507 for their calculations. Is this approach appropriate? Since the material properties of the American grade SA335P91 are comparable to those of the domestic grade 10Cr9Mo1VNbN (GB5310), and according to the provisions regarding allowable stress coefficients in the Boiler Safety Inspection Regulations, the allowable stress coefficients specified in the American boiler construction standards need not be identical to those set out in said regulations.
This method of referencing allowable stress is not permitted for pressure vessels, as the safety factors specified in GB/T150 and ASME are different.
Has the material been retested? Some materials have comparable performance in theory, but are much worse in practice
Using materials other than the standard ones as compressive elements can be a bit troublesome; if there is prior experience with such use, it can be simpler