What is the effect of numerous fixtures welded on the inside of a pressure vessel on its strength and stress?

Personally, I think it won’t affect the strength. As for stress, there should be some residual stress present; if you’re concerned, heat treatment can be performed.

It depends on the specifications of the fastening elements: 1. If they are just some support brackets, pre-welded components for ladder platforms or pipe supports, etc； It won’t have much impact on the strength of the equipment. Stress definitely has an impact: First of all, post-weld heat treatment may be necessary to deal with welding residual stress (depending mainly on the material and the environment) ； Furthermore, as a load-bearing component, it is necessary to evaluate the strength and stiffness of this \"fixing element\" itself, as well as the local stresses on the pressure vessel shell; stress analysis calculations may also be required when needed. 2. If it is similar to a tray (with a full circle welded around a certain cross-section, i.e., a \"complete tray\"), it should enhance the strength and stress of the shell ； However, the design tends to be conservative and does not take into account enhancements for this aspect. But there are also those whose structure allows for a reduction in the wall thickness of the housing.

Thank you! This statement is entirely correct! :handshake

What if, on the inside of the elliptical head, dense rows of support round bars are welded there? What is the effect on stress?

We encountered the same equipment. It’s a complex issue when dealing with round steel supports that are closely spaced together. First, during welding, protective measures must be taken, if necessary, to prevent deformation of the head during welding. Secondly, multiple passes of welding can be employed during the welding process, with welding carried out in several layers over multiple times; it is not recommended to complete the welding in a single pass. Again, if it is a stainless steel device, heat treatment is not required ； For carbon steel equipment that requires heat treatment, after welding, local heat treatment should be applied to the area where it is welded to the head ； For carbon steel equipment that does not require heat treatment, it is recommended to exercise proper control during welding; no heat treatment is necessary.

Thank you! This reply is quite comprehensive! :handshake

Thank you! This reply is quite comprehensive! :handshake