Butterfly valves are not only widely used in general industries such as petroleum, gas, chemical, water treatment, but also in the cooling water system of thermal power plants. Wafer and flange are two connection methods. Flanged butterfly valve has flanges at both ends of the valve body, which are connected with pipe flanges. The wafer type butterfly valve body has no flanges at both ends, only a few pilot bolt holes, and the valve is connected with the flanges at the ends with a set of bolts/nuts. The clip-on is cheap and lightweight. When choosing imported valves, use the wafer type as much as possible, which is cheap.
Wafer-type valve bolts are long in length and require higher construction accuracy. If the flanges on both sides are misaligned, the bolts will be subject to greater shearing force and the valve will easily leak.
In contrast, the wafer butterfly valve is easier to disassemble, 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 have to be disassembled.
Flanged butterfly valve seals are relatively more reliable, but the cost of the valve is relatively high.
Moreover, the wafer type butterfly valve generally cannot be used at the end of the pipeline and where the downstream needs to be disassembled, because when the downstream flange is disassembled, the wafer type valve will fall off. In this case, another short joint must be made. It is easy to disassemble, and the flanged butterfly valve does not have the above problems, but the cost will be relatively high.
Wafer-type valve bolts are generally relatively long. Under high temperature conditions, the expansion of the bolts may cause leakage, so it is not suitable for large pipe diameters under high temperature conditions.
CHINA BUTTERFLY VALVE MANUFACTURER
STV produces and offer electric butterfly valve, pneumatic butterfly valve, manual butterfly valve, wafer butterfly valve, flange butterfly valve, stainless steel butterfly valve and other manufacturers, designing national standard butterfly valve, chemical department butterfly valve, mechanical butterfly valve and export type ANSI standard butterfly valve, DIN standard butterfly valve, JIS Butterfly valve.