What are the types of flanged butterfly valves?
Flanged butterfly valves are mainly used in industrial production pipelines, its role is mainly to cut off the flow of media in the pipeline, or to regulate the size of the media flow in the pipeline.
Flanged butterfly valves are widely used in water conservancy projects, water treatment, petroleum, chemical industry, urban heating and other general industrial production pipelines, and can also be used on condensers and cooling water systems in thermal power stations.
Flanged butterfly valves are particularly suitable for making large diameter valves, and they are widely used in the field of large diameter regulation. When the flanged butterfly valve is fully open the flow resistance is small, and when the butterfly plate opening angle is between about 15-70°, the flanged butterfly valve can control the medium flow very sensitively.
In addition, because the butterfly plate of the flanged butterfly valve has wiping properties when doing rotational movement, this type of valve can be used in pipelines with suspended particles and, depending on the strength of the seal, can also be used in powder and granular media pipelines.
Classification of flanged butterfly valves
Flanged butterfly valves can be divided into soft seal flange butterfly valves and hard seal flange butterfly valves according to the sealing surface material.
Soft seal flange butterfly valve
Soft seal flanged butterfly valves use rubber, fluorine plastic and other resilient sealing materials for their sealing subs.
The sealing ring of soft seal flanged butterfly valve can be inlaid inside the valve body channel in addition to the butterfly plate periphery, when it is used as a cut-off valve, its sealing performance can reach FCI70-2:2006 (ASME B16 – 104) level VI, which is much higher than that of hard seal flanged butterfly valve; however, because the soft sealing material is limited by the use of temperature, the soft seal flanged butterfly valve is usually used in Water conservation and water treatment at room temperature.
Hard seal flange butterfly valve
Hard seal flanged butterfly valves use metal-to-metal, metal-to-fluoroplastic and multi-layer composite plates for their sealing subs.
The metal hard seal flange butterfly valve has the advantage of material, can adapt to higher working temperature, larger working pressure, service life is also longer than the soft seal, but the disadvantage of the hard seal flange butterfly valve is also very obvious, is difficult to achieve complete sealing, sealing performance is very poor, so this type of flange butterfly valve is generally used for sealing performance requirements are not high occasions, do regulate the flow of use.