Mechanical seals spring should have adequate strength
by：Luteng CNC Parts2020-09-06
Other parts, though not the major part of mechanical seals, but the choice of materials can not be ignored. Because a problem with any one part will lead to seal failure. These components include the spring seat (box), drive seat, thrust ring, screws and such sleeve and gland. Demands on their consciousness is sufficient strength and corrosion resistance.
In Fluid Machinery (such as pumps, compressors, agitator and centrifuge, etc.), working conditions should be considered the most demanding mechanical seals parts. As axial thrust bearings as force; as the heat exchanger as the heat generated by export. In the high temperature, high pressure, corrosive and other parts have been difficult to achieve static seal, require high-speed rotation, in a few millimeters wide end seal dynamic sealing surface to achieve even more difficult. In order to solve this thorny problem, the long-term practice by Laos, people have found two ways: First, the structure and material from the seal to start, to adapt them to harsh working conditions. This is the cost of higher cost, however, not fundamentally solve the problem. Once the seal failure, serious consequences. Another way is through the support facilities to improve the working environment. At present, the actual work without any aids rare mechanical seals. Such as the use of tandem high-pressure and high temperature mechanical seals pump and so must be appropriate support facilities. By supporting facilities to some of the harsh working environment has changed for the seal can be acceptable to greatly enhance the effect of mechanical seals, using the scope is broader. Mechanical sealing friction generated heat, so that Seals temperature, if not take the appropriate facilities, will have many negative consequences.
1. The increase of temperature between the liquid film vaporization seal faces, wear increased, so that seal failure:
2. Temperature to produce thermal deformation ring movement, leakage increased, wear increased;
3. Temperature also increased the corrosion medium on the mechanical seals;
4. Auxiliary ring so that the aging temperature, deterioration and failure;
5. Temperature, synthetic resin impregnated graphite, carbon and the performance degradation due to resin, immersed metal graphite ring, because of the metal melt and leak.
Thus, the temperature rise is the mechanical seal does not allow the enemy. Auxiliary facilities in order to: reduce the temperature rise that people do not want to maintain good lubrication between seal faces state, so that each part of a good mechanical seals, normal work; easily vaporized in the medium to ensure that the pressure in the sealed chamber, so that The non-vaporized; pump seal at low temperature can play the role of insulation and heating; For the crystallization of solid particles occurs and the seal of strong corrosive medium, but also maintain the seal is not compromised. Therefore, some countries known as the protection system to aid system. 1983 China Petrochemical Corporation was organized on the pump seal seven petrochemical investigation said: 'The imported seal centrifugal pump and compressor, according to different conditions with different ancillary facilities. Proved. Are reasonable structure , material good and ignore the ancillary facilities, resulting in difficult working conditions. lead to early seal failure. On the contrary, some occasions, the structure and materials is not enough to meet the requirements of working conditions, efficient facilities, urging the seal meets the conditions of work requirements, the successful operation. '
Some mechanical sealing temperature, pressure and speed is not too high, you can work without aids. However, the stability and service life of sealing point of view to consider, with supporting facilities is beneficial. Therefore, ancillary facilities should be seen as an integral part of mechanical seals, according to different working conditions, using different support facilities. Common international standards for the American Petroleum Institute, which have made specific provisions. Proper and reasonable use facilities, not only the stability but also to extend the seal life of great significance; on safe production and to reduce leakage, reduce the maintenance workload and reduce production costs to a certain extent, must be given sufficient importance