May weld gussets be added to the container shell after the hydrostatic test?/
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Hello, brothers and sisters. May I ask whether gussets can be welded on the container shell after the hydrostatic test? Personally, I think it’s not possible. But no evidence can be found. Who can tell me what the basis for whether it’s possible is? Thank you!
This post was last edited by Rose from YPES on 2015-8-6 09:37. Sure. If heat treatment or non-destructive testing is required, local heat treatment or non-destructive testing must be carried out first, followed by a hydrostatic test; if no heat treatment or non-destructive testing is required, welding may be sufficient directly.
This post was last edited by gn_1984 on 2015-8-6 at 10:36. Generally, parts that require heat treatment cannot be welded again; if welding is necessary, local heat treatment must be applied to the welded area once more. There are no clear requirements in the standards for equipment that does not require heat treatment; it should be possible to weld such equipment. This is the same principle as welding the jacket after performing a hydrostatic test on the inner cylinder of jacketed equipment.
For equipment without heat-treated pads, we weld them on-site at the installation location before lifting.
It can be welded directly; however, this weld is an E-class weld and must meet the standard requirements
It cannot be welded directly; if welding is done, it must be inspected and tested for pressure again after welding
Moderator, is this your experience? Is there any evidence? I wonder what the criteria are or what evidence exists for this. You say yes, he says no. I don’t know either who is right.
As stated in the 11.2 pressure test section for 20584, after the pressure test, if patch welding is carried out, another pressure test must be conducted. If the depth of the patch welding is small and the area welded does not come into contact with the medium, then no further action is required. As can be seen from above, if you are a supporting component or a thick gasket that requires welding with a thickness of more than 2 mm, a new pressure test is necessary. I encountered this once: a support for an electrical cabinet was welded to the casing, and the workshop welded it in the wrong location. I had them weld it again and conduct a pressure test once more. You can consider both the thickness of the pad and the forces acting on it; if it is just a minor support with little stress applied, there is no need to redo it
No problem, direct welding is possible.
I’ve learned about it; I had never considered this issue before. . .
The hanging ears on our reaction vessels are all welded on-site during installation, after undergoing hydraulic pressure tests