Can a reinforcement ring structure be used for the nozzles of low-temperature vessels?
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This post was last edited by Douwan on 2017-10-26 at 14:07. It’s a question asked by a friend of mine: the design temperature is -40°C, the design pressure is 0.8 MPa, and the material used is ordinary 16MnDRI. Ask whether a reinforcement ring structure can be used for energy savings in manholes or access tubes. It’s a minor issue, but it can be explored in depth; everyone is welcome to discuss it actively
I was wrong; it’s 16MnDR material
Low-temperature vessels do not rule out the use of reinforcement rings for strengthening; each case must be analyzed on its own. For this vessel, since the pressure is low and it is made of 16MnD material, using reinforcement rings is feasible. However, it is necessary to ensure full penetration welding across the entire cross-section, as well as to avoid the formation of sharp corners.
You’ve covered it quite comprehensively. That is indeed the case; GB150 does not restrict the use of reinforcement ring structures in low-temperature equipment. Similarly, HG/T 20585 only specifies that \"integral reinforcement or thick-walled tube reinforcement should be used as much as possible.\" Therefore, regarding reinforcement rings, additional requirements have been added, specifying the use of a fully welded-through structure with rounded transitions. However, in light of the requirement in GB150 that \"sudden changes in the structural shape should be avoided as much as possible to reduce local stresses\", along with the fact that welds between fittings and the cylinder are prone to stress concentration due to welding characteristics, it is understood that many organizations include a provision in their own design regulations stating that reinforcement rings should not be used in low-temperature vessels. Moreover, following the practices of certain large organizations, more and more people gradually come to believe that reinforcement rings cannot be used in low-temperature vessels.
For those who are interested, you can take a look at the following two links, both of which discuss open-hole reinforcement in cryogenic vessels. But I still hope to explore it actively and in depth. In the end, a summary will be created to ensure that whenever users search for this question on Haichuan, it can be resolved. http://bbs.hcbbs.com/thread-1318371-1-1.html http://bbs.hcbbs.com/thread-372210-3-1.html
That makes perfect sense; it’s a matter that requires comprehensive consideration of factors such as the equipment’s structure, operating conditions, the toughness of the materials used, and manufacturing quality. Of course, from a design perspective, using an overall reinforcement structure that results in lower local stresses is safer, but this often leads to increased costs for the equipment.