For cladded tube sheets, what is the appropriate number of layers?
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For cladded tube sheets, what is the appropriate number of layers?
It also depends on the type of sealing surface; after machining, it should be no less than 3 mm； If it’s a concave-convex surface or a tenon-mortise surface, it needs to be even larger.
Just follow the requirements in your drawings, and add the necessary machining allowance. Just by asking that, no one can give a specific figure.
Regarding this issue, it’s best to reply that 100mm should be piled up, and do it gradually
First, consider a machining allowance of around 3 mm; in addition, the deformation that occurs after cladding the tube sheet must also be taken into account. Generally, the deformation is greater in the central area after cladding. This deformation varies depending on the diameter and thickness of the tube sheet, as well as the cladding process used. Manufacturers have their own set of empirical data and control methods for managing this issue.
For tube sheets subjected to conventional surfacing, the clad layer is usually 12 mm thick, the transition layer is 6 mm thick, and the surface layer is also 6 mm thick.
This post was last edited by Clever Xiaoming on 2016-12-19 08:56. The person above is correct; earlier this year I built an ASME composite plate heat exchanger, with a 12mm weld layer on the tube sheet, a 6mm transition layer, and another 6mm weld layer, resulting in a total thickness of 10mm after processing. Other flanges can have a 6mm transition layer and a 3mm weld overlay; however, the tube sheet can also have a thin weld overlay. In my case, the weld overlay is thicker because a expansion groove is required. Our spectral analysis, ferrite measurement, and corrosion tests all came back satisfactory.
It depends specifically on the requirements for the surfacing layer. Generally, welding overlap is required for the first or second layer; only then is the appropriate material needed. So at least three layers or more are needed. Welding procedure qualification is required
I agree with the views expressed by those above; both the transition layer and the surface layer should be no less than 3 mm thick, while the weld layer after processing should be 10 mm thick. But I’m not sure what requirements everyone has regarding the technical specifications for cladded tube sheets.