In Article 98, Paragraph 3 of Chapter 7 of the standards, what is the appropriate duration for \"maintaining the pressure for a sufficient time to conduct inspections\"?
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In Article 98, Paragraph 3 of Chapter 7 of the standards, what is the appropriate duration for \"maintaining the pressure for a sufficient time to conduct inspections\"?
There aren’t too strict restrictions, provided there is enough time to inspect all welds. Larger containers definitely take more time, while smaller containers with fewer welds obviously take less time
This is enough time; it’s sufficient for checking. That’s all that’s needed
I also asked an experienced quality assurance engineer this question, and he said the same thing as what was said on the second floor. Because continuous stamping to maintain pressure is not allowed during the testing process.
Recently, I accompanied an inspector (expert level) to inspect a waste heat boiler; the pressure retention time was 1 hour, after which the pressure drop was checked.
The pressure holding time for our medium-pressure boilers during testing is not less than half an hour, during which the pressure-bearing components as well as valves and flanges are inspected. Finally, depressurize according to the procedures.
After maintaining the pressure at the test pressure for a certain period of time (30 minutes for containers, 20 minutes for boilers), it is reduced to the operating pressure. There is no specific time limit; as long as all welds can be inspected.
In our company, when testing pressure vessels, we generally determine the holding time at which the test pressure is reduced to 80% as 30 minutes； Here, there is sufficient time for ordinary pressure vessels to have their various welds and base metal inspected. According to the requirements of the Code, it is sufficient to complete the inspection of the equipment.
Haha, the correct answer to this question is as follows: “Long enough time” means the amount of time required for the pressure to stabilize; once it has stabilized, then an inspection can be carried out