Should the airtightness test of the heat exchanger be conducted in the tube side or the shell side?
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This post was last edited by zhangjuhua on 2022-5-7 21:35. 1. For the heat exchanger, the shell side is highly toxic while the tube side is non-toxic. Should gas tightness be ensured on the shell side or the tube side, or on both? Some netizens suggested that the inspection should be carried out on the shell side rather than the tube side, as otherwise the tube ends would not be tested; it’s not clear whether this makes sense. Some others said that airtightness checks should be done on both the tube side and the shell side, while still others suggested that they should be performed only on the toxic side, that is, the tube side. 2. In the case of a heat exchanger where the tube side contains highly toxic substances while the shell side is non-toxic, should airtightness checks be done on the shell side or the tube side, or on both?
It is done in the shell side; not only are the pipe fittings checked, but other areas as well.
On the side of the shell side that contains the hazardous media
This depends on the type of heat exchanger: 1. Fixed-tube plate heat exchangers, U-tube heat exchangers, kettle-type reboilers (U-tube bundles), and stuffing box heat exchangers: first the shell side and then the tube side； 2. Floating-head heat exchangers, kettle-type reboilers (floating-head tube bundles) ； Manage the tube side first, then the shell side ； 3. Others: there is also simultaneous and step-by-step progression.
To ensure that all possible leakage points can be detected, pipe ends must be taken into consideration.
In other words, both the shell side and the tube side need to be made airtight
The key is to determine where you want to conduct the inspection: if you want to check the tube bundle, then you go with the tube side; if you want to check the external floating head, then you go with the shell side. Moreover, in most heat exchangers pressure testing is carried out, and to check for airtightness, only the flanges at the connections as well as the sealing surfaces on the floating head or tube box sides can be inspected – the tube bundle cannot be checked in this way
When the shell side poses an extremely high level of hazard, a leakage test is conducted after the pressure test of the shell side. The inspection generally focuses on checking for leaks at the welds between the heat exchange tubes and the tube sheet on the tube sheet side, as well as at any other welds and sealing surfaces on the shell side.