The reinforcing ring means that a steel plate is welded around the opening of the shell, that is, the reinforcing ring. The reinforcing ring generally adopts the lap joint structure, and the material is the same as the wall of the machine. The size of the reinforcing ring can be determined by the standard, and the calculation can be carried out according to the principle of equal area reinforcement. When the thickness of the reinforcing ring is more than 8mm, the full penetration structure is adopted to make it work with the wall at the same time, otherwise it will not play a reinforcing role. In order to facilitate welding, the reinforcing ring can be placed symmetrically on the outer surface or inner surface of the outer wall or inside and outside surface, but in order to facilitate welding, the reinforcing ring is generally placed on the outside side to reinforce it. To check the tightness of the weld, there is a small thread of M10 on the reinforcing ring. Test the tightness of welds through compressed air from here. The reinforcing ring has now been standardized