The application range of bellows-type mechanical seals is wide, ranging from low temperatures to high temperatures, from neutral media to corrosive media, from low speed to high speed, and from ordinary to severe working conditions. All of these can be selected by changing the geometric shape of the bellows (such as inner and outer diameters, bellows thickness and number), as well as the elastic modulus of the material, which can change the spring rate of the bellows. Depending on the corrosive performance of the medium, different bellows materials can be selected. For example, for neutral media (oil and water) with no high working pressure and temperature, a simple rubber bellows seal can be used; for corrosive media (acids or bases), a four-fluorine bellows seal can be used; and for high temperature and high-speed conditions, welded metal bellows mechanical seals can be used.