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A historical review of the development of China's fan industry
The utility model relates to a fan, which is a machine used for compressing and conveying gas. Mainly used in mines, underground engineering, underground power plant boiler ventilation; ventilation and air; chemical plant high temperature corrosion gas discharge; ventilation and air conditioning and workshop atomic protective equipment, is widely used in almost all areas of the national economy, belongs to the category of general machinery.
Before the new China established, wind turbine manufacturing industry in China is almost empty, some factory only a few large city, most fans rely on imports.
After the founding of new China, the rapid development of wind turbine manufacturing industry. During the first five years of planning, has established a number of professional factories, began to produce a large number of fans. 1958, in Shenyang, Shanghai, Beijing, Tianjin, Guangzhou, Chongqing, Wuhan and other places have built a number of fan manufacturing plant. In 50s, China's wind turbine industry is basically the use of Soviet products or production drawings in accordance with the Soviet union.
In 60s China began to design and manufacture fakesu products, scientific planning committee in the State Council under the guidance of mechanical group, division of labor cooperation, design new varieties, stereotypes and work standards, and take prompt measures to improve the quality of existing products, greatly promoted the design of Chinese wind turbine manufacturing technology to improve.
In 70s, our country has developed a lot of fan products, joint design level has been increasing, the introduction of foreign production technology of wind turbine patents, digestion and absorption, trial production, so that the level of wind turbine products increased significantly.
In 80s, the introduction of foreign advanced technology fans see results, so that China's turbine compressors and large fans into the world advanced ranks in 80s.
Since 90s, China's fan industry has been greater development, the rapid growth of the total output value of the wind turbine industry. In 1999 61 enterprises production system of bureau of national machinery industry in the construction industry output value of 2 billion 614 million yuan, export delivery value of $175 million 870 thousand, the sales income of 2 billion 545 million yuan. The production and technology of fan basically meet the needs of all sectors of the national economy, some products have reached or close to the international advanced level.
China's fan industry is the main product of centrifugal compressor, axial flow compressor, centrifugal blower, roots blower, centrifugal fan, axial fan, leaf blower 7 categories of products and some other special fan. Currently there are more than and 200 series, more than 2 thousand varieties.
Two, China Fan Industry Overview
(a) fan product features
1 fan products use
The wind machine is mainly used for pumping and conveying, improve a fluid mechanical energy, mainly used in mines, underground engineering, underground power plant boiler ventilation; ventilation and air; high temperature corrosion chemical plant emissions; ventilation workshop air conditioning and atomic protective equipment. The application of the fan is very extensive. In short, it is mainly used to assist the full combustion, ventilation and transportation.
2 types of fans
According to the structure and mechanism of the fan can be divided into:
(1) centrifugal: the principle is to use the rotating impeller to produce centrifugal force or lift to transport fluid and improve its pressure. According to the way of energy acquisition, it can be divided into two types: centrifugal fan and axial fan. The fan of the utility model has the advantages of small mechanical structure, light weight, high efficiency, large and uniform flow rate and high speed. The disadvantage is that when the flow changes, the pressure and efficiency changes.
The centrifugal fan can be divided into three types according to the wind pressure:
Centrifugal fan, the wind pressure is lower than or equal to 17400N/ square meters, the gas is not compressed, mainly used in tunnel and mine ventilation, boiler air supply, air, air conditioning, ventilation, etc..
Centrifugal blower, wind pressure in the 14700 ~ 34300N/ square meters, mainly used for conveying air, sintering flue gas, gas, sulfur dioxide and some chemical gas or mixed gas.
- centrifugal compressor, the pressure in the 34300N/ square meters, mainly used for transport of nitrogen, carbon dioxide gas, tar, catalytic gas and other chemical gas, used in chemical plant, refinery, ethylene synthesis, urea synthesis, alkali refining, etc..
(2) axial flow: the principle is to rely on the impeller rotation, the blade generates lift to transport fluid, the mechanical energy into fluid energy. Because the fluid entering and leaving the impeller is called axial, axial flow fan. Belong to the high specific speed axial flow fan, which is characterized by large flow, low pressure. Axial flow fan pressure is generally 450N/ square meters to between 4500N/ square metres, mainly used in mine, tunnel, ship cabin ventilation; ventilation, industrial textile factory workplace ventilation and cooling; chemical gas discharge; thermal power plant boiler, ventilation fan; thermal power plants, metallurgy, chemical and other cooling ventilation cooling tower. At present, the axial flow fan is divided into two types: axial flow compressor and axial fan.
(3): rotary rotary body with a pair of or several special shapes (rotor gear, screw scraper or other shapes) a mechanical rotation in the shell and gas delivery or increase the pressure. The mechanical structure of the utility model is simple, compact, safe and reliable. Rotary fan blower and main blade blower two. The utility model is characterized in that the exhaust quantity is not changed with the resistance, and is especially suitable for the process flow which requires steady flow. The general use of pipeline flow is not in the scope of requirements, pressure of 0.1 2kgf/ cm2, for small converter, foundry cupola blast, oil refinery, textile factory hair spray, pneumatic conveying, transporting and industrial gas chemical industry, coal tar. Roots blower