Cracks in heat exchanger tube sheets
Thread Content
What should be done if cracks appear in the heat exchanger tube sheet after it has been in use for some time? Grinding and welding repairs have already been attempted, but cracks continue to appear during the welding process.
This question is too general; specific test reports, images of defects, material and design requirements, operating media, operating temperatures, and so on are needed in order to analyze each issue individually. Otherwise, it is difficult to make a judgment.
Without being able to see the actual item on site, it is impossible to conduct a cause analysis
In the case of a tube sheet crack, the location of the crack is identified while the equipment is shut down; the crack is mechanically removed, and after coloring shows satisfactory results, welding is performed again along with surface coloring
It can’t be simply reduced to crack removal, non-destructive testing, weld repair, and further non-destructive testing; the approach must be determined by analyzing the specific material and the nature of the defects. Some materials require preheating, post-heating, or heat treatment after patch welding; each case must be analyzed on a case-by-case basis.
If the tube sheet has cracks, crack analysis must be conducted first. It depends on the properties of your medium, the pressure conditions, and the operating conditions, such as low-temperature environments or alternating loads. It seems that your situation may be caused by stress corrosion due to medium-induced stresses, with the cracks having a tendency to propagate ； Another possibility is that the material chosen for the tube sheet is inappropriate; when operating under low-temperature conditions, the tube sheet has not been subjected to low-temperature impact.
If the tube sheet has cracks, crack analysis must be conducted first. It depends on the properties of your medium, the pressure conditions, and the operating conditions, such as low-temperature environments or alternating loads. It seems that your situation may be caused by stress corrosion due to medium-induced stresses, with the cracks having a tendency to propagate ； Another possibility is that the material chosen for the tube sheet is inappropriate; when operating under low-temperature conditions, the tube sheet has not been subjected to low-temperature impact.
This can’t be fixed with just a patch; there’s an issue with the choice of materials or their treatment
What material the tube sheet is made of, the operating conditions under which it is used, and where the cracks appear – the original poster should clarify these points; otherwise, all we can do is guess