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When there is a failure in the mechanical seal components, it is necessary to replace those components or improve their machining precision. Enhancing the machining precision of the mechanical seal itself as well as that of other components in the pump is highly beneficial for the performance of the mechanical seal. To improve the sealing performance, high requirements are placed on the surface finish and flatness of the friction surfaces of the stationary and rotating rings. The width of the friction surfaces of the stationary and rotating rings is not large, generally ranging from 2 to 7 millimeters. I. Principles of mechanical seal leakage: Leakage in mechanical seals can be caused by various factors; we must address each issue on a case-by-case basis. To minimize leakage as much as possible, mechanical seals must be installed in strict accordance with the technical specifications, and attention should also be paid to the following points. 1) The assembly should be clean and smooth. The components, tools, lubricants, and cleaning materials for mechanical seals must be extremely clean. The sealing surfaces of the stationary and rotating rings should be wiped with soft gauze. 2) Trim, chamfer, and round off. The chamfers on the shaft, seal end caps, etc. must be polished smoothly, and the relevant radii on the shaft and end caps should be sanded until they are shiny. 3) When installing the auxiliary sealing ring, the rubber auxiliary sealing ring must not be soaked or washed in gasoline or kerosene, to prevent it from expanding and deforming as well as from aging prematurely. After the stationary and rotating rings are assembled, press the compensation ring by hand to check whether it is in place and flexible, as well as whether the elastic split ring is securely positioned. After the moving ring is installed, it must be ensured that it can move axially on the shaft with ease. II. Handling of vibration and heating in mechanical seals: If the gap between the rotating and stationary rings and the sealing chamber is too small, it is necessary to increase the inner diameter of the sealing chamber or reduce the outer diameter of the rotating component, ensuring a gap of at least 0.75 mm. If the friction pair is not properly matched, the materials of the stationary and rotating rings need to be changed to make them heat-resistant and corrosion-resistant. This will reduce the vibration and heat generation of the mechanical seal. III. Handling excessive shaft play in pumps: Design an appropriate mechanism for balancing axial forces in order to eliminate axial play. To meet this requirement, for multi-stage centrifugal pumps, the design approach is to use a balance disk in combination with axial thrust bearings: the balance disk is used to balance the axial forces, while the axial thrust bearings provide axial restraint for the pump shaft. IV. Measures for dealing with pump vibration: During the manufacturing and assembly of pump products, it is necessary to follow standards and operating procedures strictly in order to eliminate sources of vibration. When installing auxiliary equipment such as pumps, motors, bases, and on-site pipelines on site, strict quality control must be applied to eliminate sources of vibration. V. Add an auxiliary flushing system: The sealing medium in the sealed chamber contains particles and impurities, which must be flushed; otherwise, the formation of crystals and the deposition of such particles and impurities can cause the springs of the mechanical seal to fail. If particles enter the friction pair, it can lead to rapid damage of the mechanical seal. Therefore, the auxiliary flushing system for mechanical seals is extremely important. It can effectively protect the sealing surfaces by cooling, lubricating, and flushing away contaminants. The above covers the applications of mechanical seals in rotating equipment and the methods for dealing with failures. When encountering mechanical seal failure issues, one should first consider the factors affecting the mechanical seal itself, and then also consider some external factors. For example, when analyzing the causes of quality failures in mechanical seals, it is necessary to take into account the impact of other components of the pump on the operation of the mechanical seal, and take measures to continuously improve its performance.