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Today, when I searched for ‘the greatest source of work stress’ on Baidu, I found the explanation given in Baidu Baike, and I found it quite reasonable. What do you all think? According to the definition in B2.1 of GB 150-1998 (see also the corrigendum issued in February 2000), the maximum allowable working pressure is “the maximum gauge pressure that the top of the vessel is permitted to withstand at the design temperature.” This pressure is calculated based on the effective thickness of the shell sections of the container, with the minimum value being taken. The function of the maximum allowable operating pressure is to set the starting pressure for the overpressure limit of the vessel, making full use of the vessel’s uniform thickness in order to maximize the pressure difference between the operating pressure and the discharge pressure of the safety valve or rupture disc, thereby ensuring a more stable operation of the pressure vessel. When the maximum allowable operating pressure is used as the starting pressure for setting the overpressure limit of a vessel, the design should take into account the use of this maximum allowable operating pressure instead of the design pressure for conducting pressure tests; GB150 specifies this in clause B4.1. The issue lies in determining the maximum allowable operating pressure for the vessel. The following technical discussions can provide a deeper understanding of the maximum allowable operating pressure. The new regulations state that: 1. The designer responsible for conducting the airtightness test must specify the maximum allowable operating pressure of the pressure vessel (see page 17); 2. For pressure vessels whose maximum allowable operating pressure is indicated on the drawings, the operating pressure of the overpressure relief device shall not exceed this maximum allowable operating pressure. Pages P13-14: 3. It is also possible to use the maximum allowable operating pressure indicated on the design drawings or nameplate to determine the setting pressure of the safety valve. Page P38: 4. During a leak test, the safety accessories should generally be installed in their entirety. Page P28: The new regulatory provisions explain that using the maximum allowable operating pressure as the operating pressure for the safety devices is done to prevent these devices from activating before the test pressure is reached during the leak test. GB150 stipulates that the maximum allowable operating pressure can be used as the starting point for determining the overpressure limit of containers; for hydrostatic tests, pneumatic tests, and leak tests, values of 1.25 times, 1.15 times, and 1.00 times the maximum allowable operating pressure respectively should be used, and this value must be indicated on the nameplate. Page P135: From these regulations, it can be seen that during leak tests, the safety devices often activate before the test pressure is reached, which indicates a contradiction. In our organization, we generally do not install safety devices during leak tests. I hope it can be coordinated in the new version of GB150. GB150 stipulates that the maximum allowable working pressure is calculated based on the effective thickness of each part of the vessel’s shell, with the minimum value being adopted. Page P134 is quite controversial. The following view is more reasonable. The maximum allowable operating pressure of a vessel shall be determined based on the design conditions and structural dimensions of all pressure-bearing elements contained within it, and in principle, it is calculated from the effective thickness of each such element. The maximum allowable operating pressure of a container can be determined using the following formula (no basis for this is found in standard regulations): Pmawp = min{Pw1, Pw2, Pw3, Pw4…}. Here, Pw1, Pw2, Pw3, and Pw4 represent the maximum allowable operating pressures for the container’s cylinder, head, flanges, and other pressure-bearing components, respectively; these values are calculated based on the design conditions and structural dimensions of each component