Please help analyze the reasons!
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During this year’s maintenance, when we were servicing one of the heat exchangers, we applied a pressure of 60 kilograms to the tube side and 30 kilograms to the shell side; both pressures were maintained successfully for half an hour. However, after replacing the pipeline at the inlet of the tube side of the heat exchanger, testing that pipeline under pressure also caused pressure to be applied to the heat exchanger itself. On two occasions, the pressure could not be maintained at 30 kilograms – leakage occurred in both cases. What could be the reason for this? Please discuss it……
Too rapid increase or decrease in voltage can lead to leakage.
It indicates there are problems with the pipeline construction.
Could you explain it in more detail? I still don’t quite understand……
Check if any of the following reasons are at play: 1. The heat exchanger is already leaking, with a slight leakage from the tube side to the shell side, which isn’t detected by the pressure gauge； 2. During system leak testing, leaks in other areas prevent the pressure from being maintained ； 3. After operating for a period of time, has corrosion (stress corrosion) occurred at the joints between the tube sheet and the heat exchange tubes?
Specifically, where do you think there’s a gap – in the weld or at the flange seal surface? If it is a sealing surface, it may be due to connection issues, gaskets, or flange deformation
You need to determine whether it is the heat exchanger that cannot maintain pressure or the connected pipelines that cannot maintain pressure, and where exactly the leakage is occurring Flange? Pipeline? Or a monitor?
It’s that the heat exchanger can’t maintain pressure – there’s a leak in the tube bundle. Strangely enough, there was no leak during the pressure testing initially, but it starts leaking as soon as pressure is applied to the pipelines