Butterfly valve applicable conditions and materials
Butterfly valves have a lot of kinds, fast cutting, have continuous adjustment. Mainly used for liquid, gas, low pressure or big diameter pipe. Applicable to pressure loss requirement is not high, the need for flow control, on-off require fast; Usually temperature under 300 ℃, pressure under 40 kg ( Butterfly valve pressure commonly used will not very high, as do domestic basically few CL600) Medium, commonly used in water and air, is not high to medium requirement, granular medium can also be used. As a type of sealing butterfly valve, it is appear in synthetic rubber, just gave it a rapid development, so it is a new kind of shut off valve. Until the 1980 s in China, the butterfly valve ACTS on low pressure valves, valve seat adopts the synthetic rubber, in the ninety s, due to an increase in foreign exchange, and hard seal ( Metal seal) Butterfly valves can develop rapidly. There are several valve factory can steadily metal sealing butterfly valve, the production of butterfly valve application field more widely. Butterfly valves can transmission and control of medium is water, water, circulating water, sewage, sea water, air, gas, liquid, gas, dry powder, mud, fruit pulp and brought a mixture of suspended solids. Butterfly valve is suitable for flow control. Because of the butterfly valve in the pipeline pressure loss is bigger, about three times the gate valve, so when choosing butterfly valves, piping system is affected by pressure loss should be considered, also should consider closing butterfly plate consistence of pipeline medium under pressure. In addition, you must consider resilient seat materials at high temperature on the operating temperature limit. The structure of the butterfly valve length and smaller overall height, opening and closing speed, and has good flow control characteristics, the structure principle of butterfly valve is most suitable for the production of large diameter valves. When the butterfly valve for control flow using one of the most important correct choose the size and type of butterfly valve, and making it work properly and effectively. Usually, in throttling and adjusting control and mud medium, shorter demand structure, opening and closing speed ( 1/4 turn) 。 Low voltage cutoff ( Small pressure difference) , recommended to choose butterfly valve. In two position adjustment, reducing channel, low noise, have spirit cave and gasification phenomenon, a small amount of leakage into the atmosphere, with abrasive medium, can choose butterfly valve. Throttling under special working conditions, or seal strict or severe worn, low temperature, Cryogenic) When using the butterfly valve such as operating conditions, need to use special design to triple eccentric metal sealing with conditioning special or double eccentric butterfly valve. Letter mau butterfly valve is suitable for the requirements to seal completely, gas leak test is zero, the demand is higher, the working temperature in - service life 10 ℃ ~ 150 ℃ water, sewage, sea water, salt water, steam, gas, food, pharmaceutical, oil and all kinds of acid and alkali, and other lines. Soft seal eccentric butterfly valve is suitable for the ventilation and dust removal pipe two-way opening and closing and adjustment, it is widely used in metallurgy, light industry, electric power, petroleum chemical industry system of gas pipeline and channel, etc. Metal to metal wire sealing double eccentric butterfly valve is suitable for the city heat supply, gas supply, water supply pipeline gas, oil, acid and alkali, and so on, as regulation and throttling device. Metal to metal surface seal triple eccentric butterfly valve as large (pressure swing adsorption (psa) PSA） Gas separation device program control valve USES, but also can be widely used in petroleum, petrochemical, chemical, metallurgy, electric power and other fields, is a good alternative for gate valve, globe valve products.