Issues with heat exchanger shells and expansion joints
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Under what circumstances are expansion joints installed in heat exchangers, and what are the principles behind this? Thank you!
We have an expansion joint in the shell side as well
If any one of the three stresses fails to meet the requirements, an expansion joint must be added
Expansion joints are used to relieve stress; they allow for free expansion and contraction during thermal changes
Due to the large temperature difference, expansion joints should be used
The fixed tube sheet structure experiences high thermal stress.
Do fixed tube sheets need to be added? Are there any additional conditions?
We have them all; some are available here and some aren’t. For example, with steam at 45 bar in the shell side, there are those with a diameter of 500, but none with a diameter of 2000.
Whether to add expansion joints must be determined through process calculations.
In the calculation of the tube sheet for fixed-tube-sheet heat exchangers, when one of the shell axial force, the axial stress of the heat exchange tubes, and the pulling force between the heat exchange tubes and the tube sheet – which are determined based on various operating conditions with temperature differences – fails to meet the strength (or stability) requirements, it is necessary to install expansion joints. In the strength verification calculations for the tube sheet, once the thickness of the tube sheet is determined, if no expansion joints are used, the strength of the tube sheet may be insufficient; however, by installing expansion joints, the required thickness for the tube sheet can be achieved. At this point, expansion joints can be installed to thin the tube sheet.