What should be done if the thickness of the head after molding is less than the minimum thickness specified in the drawings?
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This post was last edited by gn_1984 on 2017-6-29 at 14:01. Has anyone encountered the situation where, after head forming, the thickness of the formed part is less than the minimum thickness specified in the drawings? How should this be handled? The head thickness inspection report shows several selected measurement points at which the thickness is one or two places below the minimum thickness specified in the drawings. Is it possible to use patch welding to bring the thickness up to the requirements specified in the drawings? The head is made of stainless steel and is part of category III high-pressure equipment I hope fellow sailors can help come up with some ideas. Appendix: The thickness in these one or two areas is not only less than the minimum forming thickness required for the head as specified in the drawings, but it is also less than the designed thickness of the head (i.e., the calculated thickness with no corrosion allowance):funk:
Cladding = nonsense... If you design it yourself and check it based on the actual thickness, including reinforcement, it can pass if the design is adjusted; otherwise it has to be discarded. If it’s a drawing prepared by the design institute, that’s problematic. Can you convince them to prepare the drawings again?
What’s the point of designing something by yourself? It has been stated that it is smaller than the calculated thickness, so the strength will not be sufficient. I signed to declare it scrapped, but the manager disagreed; he suggested performing welding repairs, claiming that using high-quality welding materials would ensure the necessary strength. I’m stunned – is there any regulation specifying this? :'(
Let’s do it again; otherwise, if something goes wrong, I’ll hold you responsible
Theoretically, surfacing can be used as a solution; the calculated thickness of the head can be revised using the allowable stress calculation method for composite materials when considering their strength. However, this is possible only if the surfacing is applied to the entire surface, as local surfacing is not permitted. The method of head stress analysis can also be used to determine the strength of such a head, with the allowable stress values specified in GB/T150 being used for evaluation. The end cap is pressed in this condition; the quality control process at the end cap manufacturing factory is concerning – one must be careful.
Theoretically, surfacing can be used as a solution; the calculated thickness of the head can be revised using the allowable stress calculation method for composite materials when considering their strength. However, this is possible only if the surfacing is applied to the entire surface, as local surfacing is not permitted. The method of head stress analysis can also be used to determine the strength of such a head, with the allowable stress values specified in GB/T150 being used for evaluation. The end cap is pressed in this condition; the quality control process at the end cap manufacturing factory is concerning – one must be careful.
The problem is that no one is willing to take on this responsibility. No matter how good your ideas are, the management won’t approve them; they won’t sign off on them. There’s nothing you can do – the person who designed this product ends up having to take responsibility, and they use various excuses to harass people.
It’s thinner than the calculated thickness; that definitely won’t work
Also, since the equipment is now in its final form, it’s not possible to perform surfacing welding on the inside of the end caps; welding can only be done on the outside. It’s extremely difficult to weld stainless steel onto stainless steel. Who will guarantee this quality? I don’t know
The design responsibility lies with **; this must be adhered to at all costs, and one cannot listen to the managers. He signs; he’s responsible.
We all agreed in the design phase that it should be scrapped, but the production team in the workshop claims that the equipment is still usable. Given the tight delivery deadline, they don’t want to scrap it and instead want to carry out repairs such as welding. Is it possible to carry out welding? Who will ensure the quality? Is there any standard or theoretical basis for this? I haven’t seen any such thing.