China engineering mechanical seal technology development has passed 50 years of history, from the beginning of difficult start to the today's rapid development, China construction machinery sealing technology for the development of Chinese engineering machinery industry has made important contributions. Rubber and plastic seals for the development of the application of engineering mechanical seal technology which can be roughly divided into four stages.

1. The early stage (1960-1970),

This period of Chinese engineering machinery hydraulic system working pressure roughly 12-14 mpa. The sealing system with seals: 0 shape rubber sealing ring (NBR); Iron shell a cowhide rotating seal; Corrugated steel sheet cork ten metal spring end face seal; Asbestos packing; Asbestos rubber sealing gasket ten; V-shaped sealing ring (cowhide phenolic ten bakelite); V-shaped sealing ring (NBR) : 10 clip fabric soft will belong to the sealing gasket and so on.

2. Stage (1971-1980),

During this period of Chinese engineering machinery main products of the hydraulic system working pressure roughly 14-3.5 MPa. The seals used in sealing system is given priority to with rubber and plastic seals, eliminated cowhide, asbestos fiber and ten cork end face seal corrugated steel sheet. Main type D is: 0 ring (NBR, FKM); Caterpillar D chassis with floating oil seal (metal ring dry 0 charts); D insourcing skeleton oil seal sichuan BR, FKM, ZACM rotations. Reciprocating motion hydraulic and pneumatic seals D ring is 0 (NBR, FKM); U close D shooting circle (NBR, AU, BU) : V seal ten sandwiched fabrics (NBR); The cup sealing ring ten sandwiched fabrics (NBR), etc.

In these 10 years, in order to adapt to such as engineering machinery, forging machinery used medium and high pressure hydraulic technology development needs, the original machinery set up seven professional manufacturing rubber and plastic seal. In addition, to promote the development of China's sealing technology, formed in 1975 and 1975 "national hydraulic, pneumatic standardization technology committee and the" national hydraulic, pneumatic standardization technical committee rubber seal standard tumble technical committee "(with the old ISO/TCI3 / SC7) and friction to fluid sealing technology committee.

3. The consolidation and development stage (1981-1990)

Domestic engineering machinery main products of the hydraulic system pressure reached 16-40 mpa, its sealing system USES the seal form still is given priority to with rubber seal products. Main types are: O ring (NBR, FKM); Caterpillar chassis with floating oil seal charts ten metal ring (O); Lubrication sealing track with seal assembly (NBR + AU) : skeleton skeleton inside and outside the rotating oil born ten (NBR, FKM, ACM, EPDM); + metal combination sealing washer (NBR); The hydraulic cylinder piston and piston rod move close. Letters in coaxial sealing components (PTFE + NBR); The axis of rotation with dynamic hydraulic return oil seal (NBR, FKM, ACM); And the working pressure of 1? 3 mpa pressure type rotary oil seal (NBR, FKM); Two-way rotary oil seal (NBR, FKM) of medium, liquid pressure cylinder piston with O ring double action reciprocating D dynamic seal components (such as NBR + PTFE + POM).

4. The high speed development stage (after 1991)

Engineering machinery and other medium and high pressure hydraulic industrial manufacturing technology, has introduced a large number of products to promote the pace of the foreign sealing pieces merchants to enter the Chinese market. The entry of foreign capital and technology, improve the overall level of the sealing industry in China.