A reinforcing ring is a metal ring that is attached around the opening of a pressure vessel shell. It is used for reinforcing the ring (i.e., plate reinforcement) and is considered a pressure component. Typically, it is made of the same material as the shell. Depending on requirements, it can be applied on the inner, outer, or both sides of the shell. It is then processed into shape and焊接 to the shell and adapter with either full penetration or non-full penetration welds.