What is the difference between flanged butterfly valve and wafer butterfly valve?

A butterfly valve is a quarter-turn rotary motion valve that is used to stop, regulate, and start the flow. Butterfly valves are a quick open type. A 90° rotation of the handle can completely close or open the butterfly valve. Normally, flanged butterfly valves are used in systems where a positive shut-off is not required. Large butterfly valves are usually equipped with gearbox type actuator, where the handwheel is connected to the stem via a gearbox.

How can we tell flanged butterfly valve from wafer butterfly valve?

How can we tell flanged butterfly valve from lug butterfly valve?

What is the development history of flanged butterfly valve?

How can we tell flanged butterfly valve from wafer butterfly valve?

Wafer type butterfly valve and flanged butterfly valve are two common types of butterfly valve. The scope of application of both types of butterfly valve is very wide, but many people can't tell the difference between wafer type butterfly valve and flanged butterfly valve. Wafer and flanged are two connection types of butterfly valve. In terms of price, wafer butterfly valve is relatively cheaper.

The length of the bolt of wafer butterfly valve is longer, which requires higher construction accuracy. Under high temperature condition, the bolts of wafer butterfly valve may cause leakage after expansion, so it is not suitable for large diameter pipe under high temperature condition. Wafer butterfly valve cannot generally be used at the end of the pipeline and downstream needs to be disassembled. When downstream flange is removed, the wafer butterfly valve will fall off. The flanged butterfly valve does not have the above problems, but the cost will be relatively high.

Flanged butterfly valve has flanges at both ends of the body, which are connected to the pipe flange. The sealing is relatively reliable, but the valve is relatively expensive.

How can we tell flanged butterfly valve from lug butterfly valve?

The difference between a flanged butterfly valve and a lug butterfly valve is only the mounting scheme. Flanged type butterfly valves do not have attachment lugs, though they may have alignment lugs. Flanged butterfly valves are sandwiched between the flanges on the ends two lengths of pipe. In flanged butterfly valve, the body has flanged that match with pipe flange dimension.

The lug butterfly valve has protruding lugs in the periphery of a body that provides passage to bolt holes that match with those in the flanges. The lug style butterfly valve has threaded holes which allows to take off one end of the line without affecting the opposite side as it is held securely against one flange with bolts that match the threaded lugs on the valve. This makes lug butterfly valve easier to clean, inspect, repair or replace other sections of pipework as there is no need to shut down the whole system. 

What is the development history of flanged butterfly valve?

In the 1930s, the United States invented the butterfly valve. Butterfly valve was introduced to Japan in the 1950s, while it was only widely used in Japan in the 1960s. However, butterfly valve was promoted in China after the 1970s.

In the world, gate valves generally above DN300 mm have been replaced by butterfly valves. Compared with the gate valve, the butterfly valve has the advantages of short opening and closing time, small operation moment, small installation space and light weight. The disadvantage of the butterfly valve is that when used for throttling, cavitation will occur due to improper use, causing the rubber seat to peel off and damage.

Therefore, metal hard-sealed butterfly valves have been developed internationally, and the cavitation area has been reduced. In recent years, China has also developed metal hard-sealed butterfly valves. Japan has also developed a new generation of cavitation-resistant, low-vibration, and low-noise comb-tooth butterfly valve.

Learn more something about flanged butterfly valve can know the difference between flanged butterfly valve and other butterfly valves and the history of butterfly valve. In the process of butterfly valve development, a number of very powerful companies have emerged, such as Tianjin Worlds Valve Co., Ltd. Our company knows how to innovate while developing, and will also go out in the process of introducing flanged butterfly valve. Whether from quality or price, or delivery time, we can help customers to open up a further and larger market, it is wise to choose us as your business partner.