- Category: Valve
- Companies: Butterfly Valve Company
- Datasheet: Butterfly Valve Datasheet
(BFLY) A butterfly valve is a quarter turn valve (90° or less) with a circular disk as its closing element. The standard design has the valve stem running through the disk, giving a symmetrical appearance. Other designs offset the stem. Advantages include less wear and tear on the disk and seats, and tighter shut-off capabilities. When space is limited, sometimes larger valves may use a hand wheel with a gear arrangement. Butterfly valves are rather easy to maintain. These valves are used for gases, liquids, slurries, powders, and vacuum.
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Lug Style Butterfly Valve
Wafer Style Butterfly Valve
Resilient Butterfly Valve
High Performance Butterfly Valves
High Performance Butterfly Valves (HPBV) must meet certain criteria. For a butterfly valve to be determined as high performance it must:
- Provide bubble tight shutoff for the entire range of its rated ANSI differential pressure across the valve.
- Be bidirectional in nature
Typically, HPBV will be of a double or triple offset design.
Tricentric Butterfly Valve
Fire Tight Valves
When using valves in a service that may provide fuel to a fire, it is important to ensure that they are "fire tight." Typically the seat in a soft seated fire tight valve contains a metal strip that will provide additional sealing should the seat be burnt or melted away. Fire tight valves can be found on fuel gas applications, VRU systems and in other flammable systems.
Applicable Codes
The following is a list of codes applicable to butterfly valves.
- API Codes
- API Std 598 - Valve Inspection and Test
- API Std 609 - Butterfly Valves: Double-Flanged, Lug- and Wafer-Type
- AWWA Codes
- AWWA C504-06 - Rubber Seated Butterfly Valves
- AWWA M49 - Butterfly Valves: Torque, Head Loss & Cavitation Analysis
