Butterfly Valve Development
1. With the application of chemically resistant synthetic rubber on butterfly valves, the performance of butterfly valves is improved. Because synthetic rubber has the characteristics of corrosion resistance, erosion resistance, dimensional stability, good resilience, easy forming, low cost, etc., and different performance synthetic rubbers can be selected according to different use requirements to meet the working conditions of butterfly valves.
2. In order to meet the requirements of industrial applications such as high and low temperature, strong erosion, long life, metal sealing butterfly valves have been greatly developed.
High and low temperature resistance, Big size
3.With the application of high-temperature resistance, low-temperature resistance, strong corrosion-resistance, strong erosion resistance, and high strength alloy materials in butterfly valves, metal sealing butterfly valves have been widely used in industrial fields such as high and low temperature, strong erosion and long life.
4.Butterfly valves with large diameter (9~750mm), high pressure (42.0MPa) and wide temperature range (-196~606°C) have emerged, which has brought the butterfly valve technology to a new level.
Butterfly Valve Characteristics：
1. The butterfly valve has a small flow resistance when fully opened. When the opening is between about 15° and 70°, sensitive flow control is possible, so the application of butterfly valves is very common in the field of large-diameter adjustment.
2. The butterfly valve is suitable for flow regulation. Since the pressure loss of the butterfly valve in the pipe is relatively large, about three times that of the gate valve, when selecting the butterfly valve, the influence of the pressure loss of the pipeline system should be fully considered, and the strength of the disk medium subjected to the pressure of the pipeline when closing should also be considered. . In addition, the limits of the operating temperature of the elastomeric seat material at elevated temperatures must also be considered.
3. Due to the wiping nature of the butterfly disc movement, most butterfly valves can be used for media with suspended solid particles. Depending on the strength of the seal, it can also be used in powdered and granular media.
4. The butterfly valve has a small structural length and overall height, a fast opening and closing speed, and good fluid control characteristics. The structural principle of the butterfly valve is most suitable for making large diameter valves. When a butterfly valve is required for control flow, the most important thing is to correctly select the size and type of the butterfly valve so that it can work properly and efficiently.
5.Valves can be used to control the flow of various types of fluids such as air, water, steam, various corrosive media, mud, oil, liquid metals, and radioactive media. Mainly cut and throttle on the pipeline.
6. Generally, in throttling, adjustment control, and mud medium, it is required to have a short structure length, a fast opening and closing speed, and a low-pressure cutoff (small pressure difference), and a butterfly valve is recommended. Butterfly valves are available for two-position adjustment, reduced diameter channels, low noise, cavitation and vaporization, a small amount of leakage into the atmosphere, and abrasive media.
According to the structure form:
(1) Center sealing butterfly valve
(2) Single eccentric sealing butterfly valve
(3) Double eccentric sealing butterfly valve
(4) Three eccentric sealing butterfly valve
Sealing surface material:
(1) Soft sealing butterfly valve.
1) The sealing pair is made of a non-metallic soft material to a non-metallic soft material.
2) The sealing pair is made of a metal hard material to a non-metallic soft material.
(2) Metal hard seal butterfly valve. The sealing pair is composed of a metal hard material and a metal hard material.
According to the work pressure:
(1) Vacuum butterfly valve. A butterfly valve with a working pressure lower than the standard atmospheric pressure.
(2) Low pressure butterfly valve. Butterfly valve with nominal pressure PN<1.6MPa. (3) Medium pressure butterfly valve. The nominal pressure PN is a butterfly valve of 2.5–6.4 MPa. (4) High pressure butterfly valve. The nominal pressure PN is a butterfly valve of 10.0–80.0 MPa. (5) Ultra high pressure butterfly valve. Butterfly valve with nominal pressure PN>100MPa.
According to the connection method:
1, the wafer type butterfly valve
The disc of the wafer type butterfly valve is installed in the diameter direction of the pipe. The valve is fully open.
The clip-on butterfly valve is simple in structure, small in size and light in weight. The butterfly valve has two types of sealing: elastic sealing and metal sealing. Elastomeric sealing valve, the sealing ring can be mounted on the valve body or attached to the periphery of the disc.
2, flanged butterfly valve
The flanged butterfly valve is a vertical plate structure, and the valve stem is a sealing ring of the integral metal hard sealing valve.
It is a composite structure of flexible graphite plate and stainless steel plate, which is installed on the valve body, and the sealing surface of the butterfly plate is welded with stainless steel. The seal of the soft-sealed valve is made of nitrile rubber and is mounted on the disc.
3, lug butterfly valve
4, welded butterfly valve
The welded butterfly valve is a non-closed butterfly valve, which is widely used in pipelines with a medium temperature of ≤300 °C and a nominal pressure of 0.1Mpa in the production process of building materials, metallurgy, mining, electric power, etc., for connecting, opening and closing or adjusting the amount of medium.