Butterfly Valves

Since 1971, RED-WHITE VALVE CORP. has developed a trusted reputation in the industrial, commercial, plumbing, and HVAC sectors for manufacturing quality valves. Butterfly valves are a part of our extensive product line, which we offer along with superior customer service, unsurpassed fill rates, and competitive pricing. Learn more about these components, how they function, and their common applications.

What Are Butterfly Valves?

In a pipe system, these quarter-turn valves serve as on/off or modulation control of the flow of media like liquids and gases. Butterfly valves are well suited for diverse plumbing applications, from large-diameter pipes to tasks involving pressure or varying temperatures. They’re popular for their:

Superior sealing capabilities
Simplicity of design
Easy rotational motion for quick activation
Light weight
Space-saving footprint for installation
Versatility
Affordability

Butterfly Valve Parts

While butterfly valves vary in type, their simple design includes the following parts:

Valve Body

Found between pipe flanges, the body holds the valve’s components. It’s commonly available with double lug, flanged, or wafer end connections for installation.

Disc

Connected to the body of the valve and a rotating stem, the disc opens or closes off within a valve to regulate fluid flow. Depending on the material composition, orientation, and overall design, discs have varying capabilities for improved sealing, flow, and torque.

Seat

Valve seats line the inside face of the valve body, creating a structure against which the disc presses when the valve closes. This forms a tight metal anti-leak or elastomer seal for successfully shutting off all flow.

Stem

This shaft is attached to the disc, transferring the torque of actuation motion to it and enabling the disc to open and close.

Seal

In addition to providing a tight seal at valve interfaces for an application, seals also protect internal valve components from the media traveling through the system.

How Butterfly Valves Work

The stem of a butterfly valve is joined to a handle or actuator. These valves use a quarter-turn actuating mechanism, meaning that the disc aligned at a connected pipe’s center rotates by as much as 90°. As the shaft rotates, the mounted disc inside the valve body turns as well. When the disc face moves to a position parallel to the flow of media, it’s fully open to allow for media flow. At a perpendicular position, the disc, and the flow, are closed off, with the seal fitting against the seat.

Unlike ball valves, however, butterfly valves also have the capability to open or close in increments, enabling more precise flow control while still having the ability to enact a fast shutoff. The disc remains in the flow and enables pressure drop.

Types of Butterfly Valves

Butterfly valve design options can satisfy a wide range of installation and functional requirements for different applications, with varying options for disc closure, pipe connection, and actuation method.

Butterfly Valve Disc Closure Options

Butterfly valves come in concentric and eccentric disc closure designs. Concentric closures feature a shaft that goes through the centerline of a disc and a flexible rubber seat for optimal sealing. Eccentric closures place the stem on the side of the disc, opposite the flow, with minimal disc-seal contact for enhanced valve life span.

Butterfly Valve Connection Options

These components generally employ wafer valve or lug valve connections. Each type joins pipe flanges using bolts. Economical wafer butterfly valves produce efficient seals, particularly for applications that involve backflow prevention or bi-directional differential pressures. Lug-style butterfly valves are ideal for dead-end service.

Butterfly Valve Actuator Options

Butterfly valves allow for manual operation or automation. Manually, users can easily manipulate the valves using gears or handles. If the valve utilizes an electric-, hydraulic-, or pneumatic-powered actuator, the valves will open and close the disc with great rotation precision. They also provide solutions for remote operation, multiple valve sizes, and failure protection.

Butterfly Valve Applications

Given their versatility, butterfly valves find plumbing applications across an array of industries that require the transmission of fluids and gases. The following industries commonly use these valves in their applications for fluid supply, treatment, fire safety, sanitary fittings, and shut-off control:

Water supply
Wastewater treatment
Oil and gas
Chemical processing
Manufacturing
Industrial refineries
Food production and processing
Pharmaceutical production
Shipbuilding and other marine applications