How to perform stress relief treatment during hot mounting of mechanical seal sealing rings

1.Measures after installation

（1）Check the gap between the supporting surface and the insert ring. Use a 0.02mm feeler gauge to check the gap between the supporting surface of the ring seat and the back of the ring of the mechanical seal. For parts that can be inserted with the feeler gauge, repressurization is required to eliminate the gap; for parts that still fail to meet the requirements after repressurization, the insert ring should be removed and the supporting surface should be reprocessed.

（2）Use sealant to seal the gaps at the joints.All seams exisiting on the insert rings of the mechanical seal must be sealed with sealant. (This work is performed during the hot mounting process, when the component temperature drops to 80°C to 100°C.)

2.Aging and stress relief treatment 

（1）For high-pressure mechanical seal rings, mounting rings with asymmetric distribution of milling gaps or large gap sizes, in order to reduce the residual stress during the hot mounting process, they must be stored for at least one week for aging treatment after mounting, and then ground and polished to make the seal surface flatness meets the drawing requirements of the mechanical seals.

（2）If the production cycle allows, the tungsten carbide-mounted ring should be stored for aging treatment for one week after mounting, and then ground and polished to improve the reliability of its sealing performance of the mechanical seal.

（3）All hot-fitted sealing rings of the mechanical seal (except those that have been aged) must be stress relieved. The specific operation method is: place the mounted assembly in the oven, raise the temperature to 120°C, and leave it at this temperature for at least 8 hours. (Keep it in the oven overnight if possible)