Questions about hydrostatic testing
Thread Content
How is pressure testing carried out on the synthesis tower, given that there is a steam drum at the top? The drawings indicate that the hydrostatic test pressure for the shell side of the synthesis tower at the factory is 9.2 MPa, while the hydrostatic test pressure for the steam drum is 7.3 MPa. I would like to ask whether the hydrostatic pressure test specified in the drawings already includes a strength test. We have been using this pressure vessel for 7 years now; do we still need to carry out the hydrostatic pressure test as indicated in the drawings? Since the steam drum is connected to the shell side of the synthesis tower, should the entire unit be pressurized to 7.3 MPa? Should it still be 1.25 times the design pressure? Is a hydraulic test required for regular inspections? What is the difference between a hydraulic test and a pressure resistance test, and does a pressure resistance test include a strength test of the container?
We’ve all completed the pressure testing, but the post is still a request for help
Haha, so how did you suppress them later on?
Let’s go with the higher one; after all, they are connected. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A hydraulic test is a type of pressure resistance test, and both are used to evaluate the overall strength of a container. Your question is a bit strange; the synthesis tower is connected to the drum, so I don’t understand why two different test pressures are specified in the design. Are two separate containers eventually installed and connected together? If that is the case, it is likely that the design temperatures of the two devices are different; the temperature in the synthesis tower is higher than that in the steam drum, which results in different test pressures for them. It is best to ask the original designer about this issue and have them suggest solutions.
In this case, pressure testing must be carried out separately. After all, the pressure differences are quite large. (Why? ) Regular inspections no longer require pressure tests. A hydraulic test is essentially a pressure resistance test; however, pressure resistance tests also include pneumatic tests and combined gas-liquid tests, all of which are strength tests.
Pressure testing includes hydraulic pressure and pneumatic pressure, both of which fall under strength testing.
I am a pressure vessel designer. Since it are different devices, they must be pressure-tested separately, as each device has a different design pressure and design temperature, which results in varying hydraulic testing pressures. Testing at the lower pressure level will not meet the requirements for pressure testing of the other device. Testing at the intended pressure will lead to an accident. If an accident occurs, you will be responsible for it yourselves.
I’m aware of all these principles you mentioned, and I also understand the TSG specifications for fixed-volume systems. However, when connecting the steam drum to the synthesis tower, welding is used; so how can pressure testing be carried out in such a situation? We were quite cautious and did not conduct the testing at 1.25 times the required pressure, but rather at a value lower than that!
If it’s welding, then there’s a problem with the design! The data should be consistent during design