Corrosion of the heat exchange tubes or other damages.
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During a major overhaul of a heat exchanger, inspections were carried out and it was found that 3 tubes had groove-shaped depressions at a distance of 120 mm from the surface of the lower tube sheet (with a tube sheet thickness of 75 mm). Was this caused by erosion or some other type of corrosion? The pipe material is 10#, and the fluid flowing inside the pipe does not cause corrosion to this material (no similar corrosion has been observed in equipment under the same operating conditions). Have any friends encountered a similar problem?
First, the poster should specify what the working fluid is inside and outside the pipe, as well as by how much the temperature decreases or increases. It is necessary to explain these parameters in order to make a better judgment.
The shell-side medium is 45 bar steam. I wonder if this information is sufficient?
It’s a problem with the pipe itself. Seems to be a sleeved pipe?
Seamless; the long linear defect you see is a manufacturing defect.
It is currently believed that a defect in the tube’s manufacturing is the most likely cause~~~~ There is slight corrosion and pitting in the front part of the tube, but the grooves of this size that appear further along the tube can only be explained by defects in the tube itself (material defects or corrosion resulting from improper storage after manufacturing~~~ and so on~~~)
The problem lies with the pipes themselves, and it should be the responsibility of the pipe manufacturers
No such erosion marks will be formed~~~
Judging from the photos, TUBE should basically not have erosion problems, but PIT does occur, and the fluid is steam... Unless the steam contains acid, manufacturing defects of the TUBE are the most likely cause
Did you add a slow-release agent to your steam?