What is the difference between clamp butterfly valve and flange butterfly valve?

Clamp type butterfly valves and flange type butterfly valves are two common types of butterfly valves. Both types of butterfly valves have a wide range of applications, but many friends cannot distinguish between clamp type butterfly valves and flange type butterfly valves and are not familiar with the differences between the two.

The clamp and flange of butterfly valves are two connection methods. In terms of price, the clamp type is relatively cheaper, with a price roughly 2/3 of the flange. If you want to choose imported valves, try to use clamp type valves as much as possible, which are cheap and lightweight.

The bolt length of the clamp type valve is relatively long and requires high construction accuracy. If the flanges on both sides are not aligned, the bolt will be subjected to significant shear force and the valve is prone to leakage.

Clamp type valve bolts are generally longer, and under high temperature conditions, bolt expansion may cause leakage, so they are not suitable for large pipe diameters under high temperature conditions. Moreover, clamp type butterfly valves are generally not suitable for the end of pipelines and downstream situations that require disassembly, because when the downstream flange is disassembled, the clamp type valve will fall off, and in this case, a short joint must be made separately for disassembly. Flange type butterfly valves do not have upper problems, but the cost will be relatively high.

The clamp type butterfly valve body has no flanges at both ends, 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 if one sealing surface has a problem, both sealing surfaces need to be disassembled.

The flange type butterfly valve has flanges at both ends of the valve body, which are connected to the pipe flange for relatively more reliable sealing, but the valve cost is relatively high.