According to statistics, about 80%-95% of the leakage of the mechanical seal of the corrosion-resistant pump is caused by the friction of the seal end face. In addition to keeping the sealing surfaces parallel, the main problem is the material of the friction pair.
The mechanical seal friction pair material should meet the following conditions:
1) High mechanical strength, able to withstand pressure and pressure deformation;
2) It has dry abrasion resistance, high load resistance, and good self-lubrication;
3) The mating material has good running-in, without excessive wear and dual corrosion;
4) Good wear resistance and long life;
5) Good thermal conductivity and heat dissipation;
6) Good high temperature resistance;
7) Good thermal crack resistance;
8) Strong corrosion resistance;
9) Small linear expansion coefficient, heat-resistant deformation and good dimensional stability;
10) Good machinability, good formability;
11) Good air tightness;
12) The density is small.
Comprehensive evaluation of friction pair materials, it is generally believed that graphite materials impregnated with resin or metal have good thermal conductivity and self-lubricating properties, and should be given priority; ceramic materials should be used for strong oxidizing media; ceramic materials should be used for media containing particles; hard For hard friction materials, such as tungsten carbide-tungsten carbide; strong corrosive media, filled PTFE-ceramics should be selected.
