Analysis of four stages of application of sealing technology in construction machinery in China
After more than 50 years of development history, China's construction machinery sealing technology from the beginning of the difficult start to today's rapid development, for China's construction machinery industry has made an important contribution. Among them, the development process of engineering machinery sealing technology with rubber and plastic seals as the main application can be divided into four stages.
1. initial stage (1960-1970 years)
During this period, the working pressure of China's construction machinery hydraulic system is approximately 12-14MPa. The sealing system uses the seal: 0 rubber seal (NBR); a leather shell rotary oil seal; end face corrugated steel skin ten cork ten metal spring sealing; asbestos; asbestos rubber gasket ten; V ring (ten leather ten phenolic bakelite); V ring (NBR ten clip fabric: soft metal gasket and so on.
2. stage of Entrepreneurship (1971-1980 years)
During this period, the hydraulic system working pressure of the main products of China's construction machinery is about 14-3.5MPa. The seals used in the sealing system are mainly made of rubber and plastic seals, and the end face seals of ten kinds of cork, such as cattle hide, asbestos fiber and corrugated steel skin, are eliminated. The main types of D are: 0 shape seal ring (NBR, FKM); crawler D chassis with floating oil seal (metal ring dry 0 Figure); D inner package skeleton rotary seal oil Chuan BR, FKM, ZACM). Hydraulic and pneumatic reciprocating seals D have 0 shape sealing ring (NBR, FKM); U shaped dense D ring (NBR, AU, BU):V shape sealing ring (NBR ten clip fabric); cup shaped sealing ring (NBR ten clip fabric) and so on.
In the past 10 years, in order to adapt to the development of medium and high pressure hydraulic technology, such as construction machinery, forging machinery and so on, 7 professional rubber and plastic sealing parts factories were set up by the former Ministry of machinery. In addition, in order to promote the development of Chinese sealing technology, and in 1975 1979 set up a "national hydraulic and pneumatic Standardization Technical Committee and a" national hydraulic and pneumatic rubber seal Standardization Technical Committee of Standardization Technical Committee of "(corresponding to the old ISO/TCI3/SC7) to learn and friction fluid sealing technical committee.
3. consolidation and development phase (1981-1990 years)
The working pressure of the hydraulic system of the main products of the domestic construction machinery reaches 16-40MPa, and the sealing form used in the sealing system is mainly made of rubber and plastic sealing products. The main types are: O ring (NBR, FKM); floating seals for crawler chassis (Fig. ten O shaped metal ring); sealing component lubrication sealed track (NBR+AU): inner frame and an outer frame rotary oil ten (NBR, FKM, ACM, EPDM); combined sealing washer (NBR+ metal); the hydraulic cylinder piston and piston. A coaxial seal assembly (PTFE+NBR); the axis of rotation with hydraulic oil reflux (NBR, FKM, ACM); and the working pressure is 1? Pressure rotary oil seal 3MPa (NBR, FKM); two-way medium rotary oil seal (NBR, FKM), with a supporting ring double acting reciprocating dynamic seal component D the pressure cylinder piston liquid O (NBR+PTFE+POM) etc..
4. high speed development stage (after 1991)
Construction machinery and other medium and high pressure hydraulic industry has introduced a large number of product manufacturing technology, and promoted the pace of foreign sealing merchants entering the Chinese seal market. The entry of foreign capital and technology has improved the overall level of China's sealing industry.
In the era of progress, technology innovation, future China engineering mechanical seal technology will be more and more powerful, how to maximize the use of advanced technology to create value and scientific research goal, human beings do not have a dream every hour and moment, we also look forward to the future of the Chinese engineering machinery sealing technology will be the development of more avant-garde, more advanced.
