Unclear aspects in pressure vessel flange standards
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This post was last edited by zjq1962 on 2017-12-13 10:33 1. In the standard table 6, the lower limit of the operating temperature in the remarks column is 20 degrees and 0 degrees, which does not target special materials. According to the temperature limit for materials used in GB/T150.2, 20 degrees is for Q235B material, 0 degrees is for Q235C material, the nominal diameter limit is for 20MnMo material, and there are different maximum allowable working pressures in different diameter ranges. Therefore, a horizontal line should be added in the remarks column of Table 6. 2. The design pressure of Q235C specified in GB/T150.2 shall not be greater than 1.6MPa, but the Q235C material in the table can be used up to 2.5MPa. Is there any problem?
Should follow GB/T150.2-2011
What you said is not wrong at all, but the point of my question is that the container flange standard Q235C allows the use of 2.5MPa level. Is it an error in the standard, or is there another consideration.
Compare JB/T4700-2000, Question 1: The note text was misplaced during editing. Question 2: When the flange standard was revised, the modifications to GB150 were not noticed. The design pressure of Q235C in GB150-1998 is ≤2.5MPa. Therefore, it should be an error in the standard revision.
The formulation of standards requires a first draft, a draft for comments, a final draft, and submission for approval. There are still such low-level mistakes!
The people who set the flange standard and the people who set the GB150 are not the same people:P