Butterfly valves have 2 connection methods: wafer and flange. In the cylindrical channel of the valve body of the butterfly valve, the disc-shaped butterfly plate rotates around the axis, and the rotation angle is between 0° and 90°. When it rotates to 90°, the valve is fully opened. Butterfly valve, also called flap valve, is a kind of regulating valve with simple structure, and it can also be used for on-off control of low-pressure pipeline medium. Can be used to control or media all kinds of media, such as water, gas, oil, food, etc.
In terms of price, the wafer type is relatively cheap, and the price is roughly 2/3 of the flange.
The length of the bolts of the clip-on valve is longer, and the requirements for construction accuracy are higher. If the flanges on both sides are not aligned, the bolts will be subjected to large shear forces and the valve is likely to leak.
Wafer type valve bolts are generally longer. Under high temperature conditions, the bolts may cause leakage after expansion, so it is not suitable for large pipe diameters under high temperature conditions. In addition, wafer-type butterfly valves cannot generally be used at the end of the pipeline and downstream where it needs to be disassembled, because when the downstream flange is removed, the wafer-type valve will fall off. In this case, a short section must be made in addition. In order to disassemble, the flange type butterfly valve does not have the above problems, but the cost will be relatively high.
There are no flanges at both ends of the body of the wafer type butterfly valve, only a few guide bolt holes, and the valve is connected to the flanges at both ends with a set of bolts/nuts. In contrast, disassembly is more convenient, and the cost of the valve is lower, but the disadvantage is that there is a problem with one sealing surface, and both sealing surfaces must be disassembled.
The flange type butterfly valve has flanges at both ends of the valve body, which are connected to the pipe flange. The sealing is relatively more reliable, but the cost of the valve is relatively high.
Both flanged butterfly valves and wafer butterfly valves can be equipped with electric actuators or pneumatic actuators to achieve the purpose of automated fluid control.
Post time: Nov-25-2021