I have a question: if the medium in a tube sheet enclosure is water, is heat treatment still necessary?
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If the medium in the tube sheeted shell and tube unit is water, is heat treatment still required?
It needs to be processed. Independent of the medium, welding deformation is the main consideration.
Our idea is that since the medium is water, it’s okay if the sealing isn’t perfect; leaks are also no problem. That might work as an excuse
OP, no matter what medium is contained in the pressure vessel, a leak is absolutely not acceptable!
Although separate requirements can be specified for the tube side and the shell side, the tube side does not fall under the jurisdiction of pressure vessels governed by container regulations. It is still recommended to follow the provisions of B/T151.
Since it is a heat exchanger, it is recommended to carry out heat treatment on the carbon steel tube box with partitions in accordance with the requirements of GB/T151.
For tube boxes made of carbon steel and low-alloy steel materials with split diaphragms, if no heat treatment is applied, welding stresses may lead to leaks during operation; these can be internal leaks, resulting in a short circuit between the two sections, which will more or less affect the heat transfer efficiency； Second is external leakage; no matter what the medium is, it’s definitely not acceptable for a device to have external leakage. Isn’t it just about reducing heat? Even this has to be spared?
There is a reason for such standards; to what extent of leakage can you accept it?
It can’t be considered that way. A leak in the tube side medium might indeed be harmless, but if the tube fittings fail, the shell side medium could leak into the tube side; therefore, even when the tube side contains water, it is still necessary to ensure good sealing performance.
For those that require heat treatment, the heat treatment of tube boxes with partitions is primarily aimed at eliminating the residual welding stresses between the partitions and the tube box shell, thereby preventing leakage at the sealing points caused by welding deformation. Although the medium flowing through the tubes is water, there are still requirements regarding the amount of leakage; after all, it’s not acceptable for water to keep leaking continuously from the connection between the tube box and the shell during normal operation:lol
7th floor: victory: