Matching medium characteristics is the primary technical prerequisite for selecting pump mechanical seals. For corrosive media, the rotating and stationary rings of pump mechanical seals should be made of corrosion-resistant hard materials like silicon carbide and silicon nitride, while the sealing rings should be paired with corrosion-resistant elastomers such as fluororubber and perfluoroelastomer. This prevents seal failure caused by medium erosion at the material level. Additionally, selection should be optimized based on medium viscosity and particle content: for high-viscosity media, seal face structures with low friction coefficients are preferred; for media containing solid particles, sealed structures with flushing circuits should be adopted to avoid abrasive failure from particles embedding in the seal faces.

Matching working condition parameters is a core technical step to ensure the stable operation of pump mechanical seals. For high-temperature conditions (medium temperature > 150℃), metal bellows-type structures should be prioritized. Their springless design prevents high-temperature creep failure, and their seal face heat resistance outperforms conventional spring-type structures. For high-pressure conditions (seal chamber pressure > 1.6MPa), the rated pressure resistance of the seal components must be verified to ensure it is at least 1.2 times the actual working pressure, preventing seal face deformation and end-face specific pressure imbalance caused by high pressure. Furthermore, seal face width and material hardness should be optimized based on pump shaft speed; for speeds > 3000r/min, high-strength silicon carbide should be used for the seal faces to reduce wear rates from high-speed friction.