What is a valve?
A valve is the general term of the control parts that guide, stop and regulate the fluid (gas and liquid).
For example, valves includes general valves, gate valves, globe valves, cast steel valves, etc. The valve that mainly controls the discharge and consumption of fluid is also called a plug. There are water hydrants, water distribution hydrants, gas hydrants, fire hydrants, etc.
Valves play an important role in the piping of infrastructure (power, waterway and gas), construction equipment, installation industry, machinery industry, transportation organs, etc., and they can not function independently. Therefore, their technological trends correspond to the change of surrounding environment.
History of valves
a) History of the valve industry
The valve can be traced back to the unearthed wooden objects which were supposed to be valves in the ancient Egyptian ruins unearthed in 1000 BC. Moreover, in ancient Roman times, there were pipe facilities in noble families and bronze valves in their exports.
b) History of valve technology
1) Enrichment and strengthening of production technology
Corresponding to the main demand of construction equipment, the average quality and cost reduction of general valves were started. With the improvement of cast iron valve production technology, new casting method has been adopted and the material has been improved. The steel valve adopts powerful working machinery, and its precision is also improved.
2) Expansion of product specifications (working conditions)
Since the start of the temporary measures for the revitalization of machinery industry, boilers for power generation have begun to develop to subcritical, supercritical and ultra supercritical. The working conditions of the valve are also expanded, and now they can correspond to 31Mpa /566 ℃ and 25MPa / 610 ℃. In addition, with the large-scale blast furnace, the maximum hot air temperature can reach 1400℃. At the same time, corresponding efforts have been devoted.
In terms of low temperature, LNC is practical, and valves being suitable for -163 ℃ working conditions are also developed. After that, the temperature of - 253 ℃ for rocket fuel was put into practice. As a research device for nuclear fusion power generation, the experimental object at -269 ℃ also works well.
With the diversification of fluid types, the use of corrosive tantalum, titanium, resin, ceramics and other non-metallic materials is required. Fluids containing powders and solids with high hardness are also used. Specifications that require high definition cleanliness, such as semiconductor manufacturing equipment, pharmaceutical manufacturing equipment and rocket launching equipment have also been applied.
3) Product design for functional expansion
The expansion of specifications requires the use of new materials in product design. In order to realize high temperature and high pressure, the valve body is made from Cr-Mo cast steel, and the valve body and seat surface are welded with tungsten chromium cobalt alloy. Malleable cast iron and rare cast iron also contribute to the valve height. In addition to metals, resins and ceramics are also used.
As the function expands, so does the structure. With the development of new seat construction, rotary valves such as butterfly valves and ball valves have also become popular. In order to enrich the self diagnosis function in the valve, the positioner equipped with the control valve driving part also began to be intelligent with the introduction of the maglev train.
4) In order to pursue safety, fast and suitable product design was owned.
In order to deal with the water shortage problem of building piping, noise regulations related to industrial facilities, gas safety enhancement, and asbestos regulation to ensure the safety of human beings, the valves are converted into anti-corrosion valves at pipe ends for water supply, little noise valves for reducing flow sounds, socket taps and fuse gas plugs.
A valve is the general term of the control parts that guide, stop and regulate the fluid (gas and liquid).
For example, valves includes general valves, gate valves, globe valves, cast steel valves, etc. The valve that mainly controls the discharge and consumption of fluid is also called a plug. There are water hydrants, water distribution hydrants, gas hydrants, fire hydrants, etc.
Valves play an important role in the piping of infrastructure (power, waterway and gas), construction equipment, installation industry, machinery industry, transportation organs, etc., and they can not function independently. Therefore, their technological trends correspond to the change of surrounding environment.
History of valves
a) History of the valve industry
The valve can be traced back to the unearthed wooden objects which were supposed to be valves in the ancient Egyptian ruins unearthed in 1000 BC. Moreover, in ancient Roman times, there were pipe facilities in noble families and bronze valves in their exports.
b) History of valve technology
1) Enrichment and strengthening of production technology
Corresponding to the main demand of construction equipment, the average quality and cost reduction of general valves were started. With the improvement of cast iron valve production technology, new casting method has been adopted and the material has been improved. The steel valve adopts powerful working machinery, and its precision is also improved.
2) Expansion of product specifications (working conditions)
Since the start of the temporary measures for the revitalization of machinery industry, boilers for power generation have begun to develop to subcritical, supercritical and ultra supercritical. The working conditions of the valve are also expanded, and now they can correspond to 31Mpa /566 ℃ and 25MPa / 610 ℃. In addition, with the large-scale blast furnace, the maximum hot air temperature can reach 1400℃. At the same time, corresponding efforts have been devoted.
In terms of low temperature, LNC is practical, and valves being suitable for -163 ℃ working conditions are also developed. After that, the temperature of - 253 ℃ for rocket fuel was put into practice. As a research device for nuclear fusion power generation, the experimental object at -269 ℃ also works well.
With the diversification of fluid types, the use of corrosive tantalum, titanium, resin, ceramics and other non-metallic materials is required. Fluids containing powders and solids with high hardness are also used. Specifications that require high definition cleanliness, such as semiconductor manufacturing equipment, pharmaceutical manufacturing equipment and rocket launching equipment have also been applied.
3) Product design for functional expansion
The expansion of specifications requires the use of new materials in product design. In order to realize high temperature and high pressure, the valve body is made from Cr-Mo cast steel, and the valve body and seat surface are welded with tungsten chromium cobalt alloy. Malleable cast iron and rare cast iron also contribute to the valve height. In addition to metals, resins and ceramics are also used.
As the function expands, so does the structure. With the development of new seat construction, rotary valves such as butterfly valves and ball valves have also become popular. In order to enrich the self diagnosis function in the valve, the positioner equipped with the control valve driving part also began to be intelligent with the introduction of the maglev train.
4) In order to pursue safety, fast and suitable product design was owned.
In order to deal with the water shortage problem of building piping, noise regulations related to industrial facilities, gas safety enhancement, and asbestos regulation to ensure the safety of human beings, the valves are converted into anti-corrosion valves at pipe ends for water supply, little noise valves for reducing flow sounds, socket taps and fuse gas plugs.
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