1、 Development History

The development process of China's hydraulic (including hydraulic, the same below), pneumatic, and sealing industries can be roughly divided into three stages, namely: the early 1950s to the early 1960s as the starting stage; The 1960s and 1970s were the growth stage of specialized production systems; The 1980s and 1990s were a period of rapid development. Among them, the hydraulic industry started in the early 1950s with the production of Soviet style grinding machines, lathes, and other hydraulic transmissions in the machine tool industry. Hydraulic components were produced by the hydraulic workshop of the machine tool factory for self use. After entering the 1960s, the application of hydraulic technology gradually expanded from machine tools to fields such as agricultural machinery and engineering machinery. Some hydraulic workshops that were originally affiliated with host factories became independent and specialized hydraulic component manufacturers. In the late 1960s and early 1970s, with the development of production mechanization, especially driven by the provision of efficient and automated equipment for second automobile manufacturers, the hydraulic component manufacturing industry experienced rapid growth, and a group of small and medium-sized enterprises also became specialized hydraulic component manufacturers. In 1968, the annual production of hydraulic components in China had approached 200000 pieces; In 1973, there were more than 100 specialized factories producing hydraulic components in industries such as machine tools, agricultural machinery, and construction machinery, with an annual output of over 1 million pieces. An independent hydraulic component manufacturing industry was initially formed. At this point, hydraulic component products have evolved from imitation Soviet products to products that combine imported technology with self-designed products. Pressure has been developed towards medium and high pressure, and electro-hydraulic servo valves and systems have been developed, further expanding the field of hydraulic applications. The pneumatic industry started a few years later than hydraulic, and it was not until 1967 that specialized factories for pneumatic components were established, and pneumatic components were produced and sold as commodities. The sealing industry, which includes rubber seals, mechanical seals, and flexible graphite seals, started in the early 1950s with the production of extruded rubber seals and asbestos seals such as ordinary O-rings and oil seals. By the early 1960s, it began to develop and produce products such as mechanical seals and flexible graphite seals. In the 1970s, a number of professional production factories were established within the systems of the Ministry of Natural Combustion, the Ministry of First Machinery, and the Ministry of Agricultural Machinery, and officially formed the industry, laying the foundation for the development and growth of the sealing industry.

In the 1980s, guided by the national policy of reform and opening up, with the development of the machinery industry, the contradiction between basic components and main engines became increasingly prominent and attracted the attention of various relevant departments. To this end, the former Ministry of Machinery Industry established the General Basic Parts Industry Bureau in 1982, which unified the hydraulic, pneumatic, and sealing professional factories scattered in industries such as machine tools, agricultural machinery, and engineering machinery under the management of the General Basic Parts Bureau. This enabled the industry to receive guidance and support from the Basic Parts Bureau in planning, investment, technology introduction, and scientific research and development. Since then, we have entered a period of rapid development, introducing over 60 advanced foreign technologies, including more than 40 hydraulic and 7 pneumatic ones. After digestion, absorption, and technological transformation, they have all been mass-produced and become the leading products in the industry. In recent years, the industry has increased its efforts in technological transformation. From 1991 to 1998, the total investment of national, local, and enterprise self raised funds was about 2 billion yuan, including more than 1.6 billion yuan in hydraulic engineering. Through technological transformation and breakthroughs, a group of major enterprises have further improved their technological level and greatly improved their process equipment, laying a good foundation for the formation of high starting point, specialization, and mass production. In recent years, guided by the policy of promoting the common development of various forms of ownership in the country, small and medium-sized enterprises with different forms of ownership have risen rapidly and shown great vitality. With the further opening up of the country, the rapid development of foreign-funded enterprises plays an important role in improving industry standards and expanding exports. At present, China has established more than 50 production enterprises of plunger pumps/motors, planetary reducers, steering gears, hydraulic control valves, hydraulic systems, static hydraulic transmission devices, hydraulic component casting, pneumatic control valves, cylinders, air source processing triplets, mechanical seals, rubber seals and other products through joint ventures or sole proprietorships with famous manufacturers from the United States, Japan, Germany and other countries, and has introduced more than 200 million US dollars of foreign investment.

2、 Current situation

(1) Basic Overview

After more than 40 years of effort, China's hydraulic, pneumatic, and sealing industries have formed an industrial system with a relatively complete range of categories, certain production capacity, and technological level. According to the statistics of the third national industrial census in 1995, there were more than 1300 state-owned, village run, private, cooperative, individual, and "three capital" enterprises with annual sales revenue of over 1 million yuan in China's hydraulic, pneumatic, and sealing industry townships and above. Among them, there were about 700 hydraulic enterprises and about 300 pneumatic and sealing enterprises each. According to international industry statistics in 1996, the total output value of China's hydraulic industry was 2.348 billion yuan, ranking sixth in the world; The total output value of the pneumatic industry is 419 million yuan, ranking 10th in the world.

(2) Current Supply and Demand Overview

Through technology introduction, independent development, and technological transformation, the technical level of the first batch of products including high-pressure plunger pumps, gear pumps, vane pumps, universal hydraulic valves, oil cylinders, oil-free lubrication pneumatic components, and various seals has been significantly improved, and stable mass production can be achieved, providing a guarantee for improving the product level of various types of main engines. In addition, certain achievements have been made in CAD, pollution control, proportional servo technology, and other aspects of hydraulic and pneumatic components and systems, which have been used in production. At present, there are approximately 3000 varieties and over 23000 specifications of hydraulic, pneumatic, and sealing products. Among them, there are 1200 varieties and over 10000 specifications of hydraulic products (including 60 varieties and 500 specifications of hydraulic products); Pneumatic has 1350 varieties and over 8000 specifications; There are 350 varieties and over 5000 specifications of rubber seals, which can basically meet the general needs of various host products. The matching rate for major complete sets of equipment can also reach over 60%, and a small amount of exports have begun.

In 1998, the domestic production of hydraulic components was 4.8 million, with a sales volume of approximately 2.8 billion yuan (of which mechanical systems accounted for about 70%); The production of pneumatic components is 3.6 million pieces, with a sales revenue of approximately 550 million yuan (of which mechanical systems account for about 60%); The production of seals is about 800 million pieces, with a sales revenue of about 1 billion yuan (of which mechanical systems account for about 50%). According to the 1998 annual report of the China Hydraulic and Pneumatic Seal Industry Association, the production and sales rate of hydraulic products was 97.5% (hydraulic products accounted for 101%), pneumatic products accounted for 95.9%, and seals accounted for 98.7%. This fully reflects the basic connection between production and sales.