• Non-contact mechanical seal refers to a mechanical seal that is filled with a complete fluid film between the seal end faces due to hydrostatic pressure or dynamic pressure to force the seal end faces to separate from each other, and there is no rigid solid contact mechanical seal. The sealing principle and characteristics of non-contact mechanical seals determine that most of these seals have a stable dynamic pressure effect at high speeds. At low speeds, due to insufficient dynamic pressure, the probability of contact between the seal end faces increases, which affects the stability of the seal.

• With the development of science and technology, continuous innovation of construction machinery and equipment. The requirements for the sealing stability of low-speed machines have also been continuously improved. The use of non-contact seals that achieve zero leakage and zero escape in low-speed operating conditions has gradually become the status quo pursued by research and development.

• One of the forms of low-speed mechanical seals: liquid film seals

Liquid film seal generally refers to a full liquid film lubrication non-contact mechanical seal, which can reduce or eliminate the leakage of the sealed medium, and at the same time improve the lubrication condition and operational stability of the seal end surface. The low-speed liquid film non-contact mechanical seal includes deep groove liquid Two kinds of non-contact mechanical seals: membrane low-speed and shallow groove liquid membrane low-speed non-contact mechanical seals;

• Deep groove liquid film low-speed sealing:

Deep grooves on the end surface refer to grooves in various forms on the end surface of the mechanical seal with a depth of millimeters. The use of hydrostatic pressure and hydrodynamic pressure to improve the lubrication of the sealing surface;

• Shallow groove liquid film low speed seal:

The shallow groove liquid film low-speed non-contact mechanical seal mainly refers to the upstream pumping mechanical seal. Among them, the middle grooved upstream pumping low-speed seal has the best performance, and the zero-escape upstream pumping mechanical seal can effectively solve the easy vaporization of the medium. The problem of sealing conditions;

• The above two mechanical seals are a form of low-speed liquid film non-contact mechanical seals. They are one of the types of low-speed seals developed. They are well matched to the above-mentioned working conditions and are outstanding for low-speed seals. Point one.