This passage focuses on the definition, application, types and characteristics of butterfly valves.
1. Definition of butterfly valves
2. Common application of butterfly valves
3. Butterfly valves'two body types
4. Differences between butterfly valves and globe valves
1. Definition of butterfly valves
Valves are used to isolate or regulate the flow of fluid, in which a disc-shaped closing member is rotated by an angle of 90 degrees or less to open or close or adjust the flow.
2. Common application of butterfly valves
Sanitary valves are made of stainless steel with good corrosion resistance, so they are used in the pharmaceutical, chemical, and food industries which have high requirements for the materials of tools.
3. Butterfly valves'two body types
Wafer Type Butterfly Valve
It is the most economical version and it is sandwiched between two pipe flanges and the flange bolts surround the valve body. The pipe flanges are connected through long bolts that cross the entire valve body. This type of connection is designed for sealing against bi-directional differential pressures and to prevent backward flow in systems designed for universal flow.
Lug Type Butterfly Valve
It has threaded lugs outside the valve body. Two sets of bolts connect pipe flanges to each side of the bolt inserts without nuts. This design enables the disconnection of one side without affecting the other for dead-end service. Lug-style They used in dead end service generally have a lower pressure rating.
Unlike lug-style butterfly valves, wafer-style butterfly valves cannot be used as pipe ends or end-of-line service. The entire line must be shut down if either side of the valve requires maintenance. Wafer style valves are manufactured to be compatible with either pneumatic or electric actuation.
4. Differences between butterfly valves and globe valves
Definition of globe valves
A globe valve, different from ball valve, is a type of valve used for regulating flow in a pipeline, consisting of a movable plug or disc element and a stationary ring seat in a generally spherical body. It is a linear motion valve used to stop, start, and regulate the fluid flow. The globe valve disk can be removed entirely from the flow path, or it can completely close the flow path. During the opening and closing of the valve, the disc moves perpendicularly to the seat.
Due to different construction, the two types of valves has several differences:
Different ways of opening and closing
Globe valve: The opening and closing parts are plug-shaped discs, the sealing surface is flat or conical, and the disc moves in a straight line along the center line of the fluid.
Butterfly valve: The opening and closing part is a disc-shaped butterfly plate, which rotates around its own axis in the valve body.
Therefore, the globe valve can only be fully opened or fully closed, and the flow cannot be adjusted. The butterfly valve can control the flow rate so it is more flexible.
Different characteristics
Globe valve: The opening or closing stroke of the stem of it is relatively short, and the shut-off function is very reliable. Since the change of the valve seat opening is proportional to the disc stroke, it is very suitable for flow adjustment.
Butterfly value: It features simple structure, small size, light weight, low material consumption, small installation size, fast switching speed, reciprocating rotation of 90 degrees, and small driving torque and other. They are used to cut, connect and adjust the media in the pipeline. They have good fluid control characteristics and sealing performance.
Different working principles
Globe valve: The closing principle of stop valve is to make the sealing surface of disc and seat close together by the pressure of valve rod to prevent the flow of medium.
Butterfly valve: A valve that opens, closes or regulates the flow of medium by reciprocating about 90 degrees with disc-type opening and closing parts.It not only has simple structure, small volume, light weight, less material consumption, small installation size, small driving moment, simple operation and rapid, but also has good flow regulation function and sealing characteristics.
In addition to the products introduced in this article, Wenzhou Xusheng Machinery Industry can also supply a wide range of products such as inlet valves, anti-mixing valves, pressure relief valves, manual and pneumatic butterfly valves, check valves, diaphragm valves, ball valves, pipe fittings, well covers, pumps, pipelines, water pipes and many more. If you require any further information on our products, please do not hesitate to contact us.
