Butterfly Valves

Do butterfly valves need gaskets?

This really depends upon the style and make of the butterfly valve but ours do not as they utilise the seat which overhangs the body of the valve to form the gasket. This makes installation and stocking much easier.

 

How does a butterfly valve work?

A butterfly valve operates by rotating a disc or vane perpendicular to the flow direction within the pipeline.

• When the valve is open, the disc is parallel to the flow, allowing fluid to pass through.
• When the valve is closed, the disc rotates perpendicular to the flow, blocking the passage of fluid.
   

How to install butterfly valve?

Butterfly valves are installed between two flanges in a pipeline using bolts and nuts.

Proper alignment and torqueing of the bolts are essential to ensure a leak-tight connection.

1. Begin by preparing the pipeline where the valve will be installed, ensuring it's clean and properly aligned.
   Before installation, confirm the correct orientation of the valve to maintain the desired flow direction, typically indicated by an arrow on the valve body.
    
2. Next, place gaskets on both sides of the valve to create a tight seal. Position the valve between the flanges of the pipeline, ensuring it's centered and aligned correctly. Insert bolts through the bolt holes on the flanges and align them with the corresponding holes on the valve. Secure the bolts using nuts.
    
3. When tightening the bolts, follow a crisscross pattern to evenly distribute pressure and prevent warping of the valve body. It's essential to achieve the recommended torque specified by the valve manufacturer to ensure a secure connection.
    
4. After tightening the bolts, double-check the alignment of the valve and ensure it's securely fastened to the pipeline.
    
5. Finally, perform any necessary testing or inspection to verify proper installation and functionality of the butterfly valve.

 

Are butterfly valves directional?

This depends upon the type of butterfly valve but generally center line butterfly valves can take flow in either direction.

 

Can butterfly valve be used for flow control?

To some extent butterfly valves can be used for flow control by adjusting the position of the disc to regulate the flow rate within the pipeline. This is generally not a very accurate way of achieving flow control however.

 

Can butterfly valves be used for throttling?

While butterfly valves can be used for throttling applications, BUT they are generally better suited for on/off service or moderate throttling.

For precise throttling control, specialized control valves may be more suitable.

 

How to open butterfly valve?

To open a butterfly valve, rotate the valve handle or actuator in the appropriate direction (usually clockwise) until the disc is parallel to the flow direction.

 

What is lugged type butterfly valve?

A lugged butterfly valve has threaded holes (lugs) on the valve body that allow it to be bolted directly to a pipeline without the need for additional flanges.

This design simplifies installation and removal of the valve from the pipeline.

 

What is the difference between lug and wafer butterfly valves?

The main difference between lug and wafer butterfly valves is their connection method.

• Lugged butterfly valves have lugs or threaded holes on the valve body for bolting directly to the pipeline.
• Wafer butterfly valves are sandwiched between flanges in the pipeline without additional bolting.

 

When to use butterfly valve?

Butterfly valves are commonly used in applications where a simple and economical valve solution is required for on/off or moderate throttling service.

They are suitable for various industries including water treatment, HVAC, chemical processing, and more.

 

What are Ductile Iron Butterfly Valves?

Ductile Iron Butterfly Valves are butterfly valves with bodies made of ductile iron, a type of cast iron that has been treated to enhance its strength and ductility.

 

What are Double Acting Butterfly Valves?

Double Acting Butterfly Valves are butterfly valves that are actuated using a pneumatic, electric or hydraulic actuator. These actuators operate in both the opening and closing directions, providing bidirectional control of the valve.

 

The role of pneumatic butterfly valve

Pneumatic butterfly valves use compressed air to actuate the valve mechanism, providing reliable and efficient operation for various industrial applications. They offer quick response times and can be easily automated for remote control.

 

The role of air actuated butterfly valve

Air actuated butterfly valves use compressed air to actuate the valve mechanism, allowing for remote operation and automation. They are commonly used in applications where manual operation is impractical or where precise control is required.

 

What is Double Flanged Butterfly Valve?

A Double Flanged Butterfly Valve is a type of butterfly valve that features flanged connections on both ends, allowing it to be installed directly between flanges in a pipeline without the need for additional couplings or adapters.

 

What is Electric Butterfly Valve?

An Electric Butterfly Valve is a butterfly valve actuated by an electric motor or actuator. These valves offer precise control and can be easily automated for remote operation using electrical signals.

 

What is the role of butterfly valves with stainless steel discs?

Butterfly valves with stainless steel discs offer enhanced durability, corrosion resistance, and reliability, making them suitable for demanding applications where harsh fluids or aggressive environments are present.