Issues regarding the selection of allowable stress values for ASME materials
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Without considering other restrictive requirements of standard specifications, if ASME materials are used and calculations are carried out using the formulas in GB150, should the allowable stress be taken directly from the values specified in Section D of ASME Volume II, or should it be calculated based on the properties of the materials in Section D along with the safety factors prescribed by GB150?
After careful consideration, for ordinary carbon steel or stainless steel at low to medium pressures, it is recommended to use the ASME allowable stress values for calculations; this simplifies things for designers, enhances the safety of the equipment, and does not result in significant additional costs. For large-diameter, high-pressure equipment, it is necessary to weigh the economic differences between the two methods. Additionally, the design operating conditions of the equipment need to be considered. In cases with complex operating conditions, it’s not sufficient to simply divide the tensile strength or yield strength by a safety factor.
Take a look at Amendment 1 to GB150; materials such as SA516, 537, and 387 have been included in GB150, and relevant requirements regarding their allowable stresses and other aspects have been specified. For ASME materials not listed in GB150, it is advisable to use the ASME standards for design.
Calculations are performed using the coefficients specified in the design codes. . . For example, materials based on ASME standards, when used in GB150 applications, should be handled in accordance with the requirements of GB150
Wait for more knowledgeable people to give a clear answer
The HG standards specify that the allowable stress can be calculated using domestic safety factors; this results in a higher allowable stress and thus less material consumption. However, for critical equipment or designs that follow a more conservative approach, it is also acceptable to use the ASME allowable stress values.
Could you be more specific? What is the HG standard, which chapter?
I think the replies from the fellow travelers upstairs are all very professional. If we talk about “authorities,” then they are the industry standards and GB150. Clause 4.4.1 of GB150.1-2011: The allowable stress for materials in this standard is determined in accordance with GB150.2 and the relevant referenced standards. The allowable stress for steel materials (except for bolt materials) is determined in accordance with Table 1, while the allowable stress for steel bolt materials is determined in accordance with Table 2. Therefore, for materials not listed in GB150.2 (such as ASME materials), the allowable stress of steel shall be determined in accordance with Tables 1 and 2 of GB150.1. However, it is permissible to directly use the maximum allowable stress value S from ASME Section II, Division D, although it may be somewhat conservative. A conservative design does not violate the code requirements and GB150, as long as the owner has no objections. When using ASME materials, it is usually a replicated design from foreign projects; the materials and dimensions of the equipment are already determined. It is more convenient to simply use the maximum allowable stress values specified by ASME as the allowable stress values for GB150.