The main material of the container is 316L; can 304 be used for the support pads?
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It seems that the material of the shimming plate for the support, as per the specifications, should be the same as that of the main material. What will be the consequences if there is a discrepancy? For example, if the material of the equipment’s cylinder is 316L, does the material of the support pad plate have to be 316L as well? Can it be 304? The shimming plate also does not come into contact with the material.
According to the specifications, the material of the bearing pad should be the same as that of the main material. If the material of the cylinder body of the equipment you are using is 316L, then the support pad should also be 316L. This is to ensure that during use, the coefficients of thermal expansion and chemical properties of the two materials are similar, thereby avoiding problems caused by minor differences between them, such as poor airtightness or leaks. Although the shims do not come into direct contact with the material, they bear the weight of the equipment. If the materials used are not compatible, it may lead to issues such as failure of the supports and deformation of the equipment; therefore, it is best to use materials that are identical to those of the main components in order to ensure the stable operation of the equipment. .
This post was last edited by qqsbig001 on 2023-4-19 at 13:11. Statistics: NB/T47065.1-2018 – For saddle supports, the material of the gasket plate should generally be the same as that of the container’s cylinder body； SW6-2011: For saddle supports, the pad width b4 and thickness δrn must be entered. NB/T47065.2-2018 Leg-type supports: The struts or pads that are welded directly to the equipment housing shall be made of the same material as, or compatible with, that of the housing ； SW6-2011: For leg-type supports, the thickness δa of the shimming plate and the material of the shimming plate must be entered. NB/T47065.3-2018 Ear-type supports: The material of the gasket should generally be the same as that of the container ； SW6-2011: For ear-type supports, the gasket thickness δ3 must be entered. NB/T47065.4-2018 Support-type bearings: The material of the bearing pad should generally be the same as that of the container head ； SW6-2011: For supported bearings, the thickness δ3 of the shimming plate must be entered. NB/T47065.5-2018 Rigid ring supports: Support elements that are welded directly to the container cylinder, such as gussets or stiffening plates, as well as ring plates (when no gussets are used), should have the same or similar chemical composition and mechanical properties as the cylinder material ； SW6-2011: For rigid ring supports, the nominal thickness δb of the gasket must be entered.
If the owner agrees, it’s fine to change the shims from 316L to 304; I don’t see any problem with that. But why go to the extra trouble of using something special?
Strictly speaking, it is not allowed; the materials welded to the main equipment must be the same as the materials of the main equipment itself. Unless the owner agrees
Welding of dissimilar steels can affect the main structure; many non-standard atmospheric pressure vessels are fabricated in this way
It’s best not to make any changes, but if 304 is used, it should also work.
In principle, there’s no problem, but it’s necessary to communicate with the client and get their approval through design
What are the principles for selecting a shell material that matches well?