What is the function of butterfly valve?

The main function of these valves is to control the flow of liquids through a section of pipe. Butterfly valves are mainly used in waste treatment systems. They are extremely durable and need minimal maintenance. Butterfly valves operate like other quarter turn valves.

Subsequently, one may also ask, how does a butterfly valve work?

The "butterfly" is a metal disc mounted on a rod. When the valve is closed, the disc is turned so that it completely blocks off the passageway. When the valve is fully open, the disc is rotated a quarter turn so that it allows an almost unrestricted passage of the fluid.

Also, do Butterfly Valves have a flow direction? The butterfly valves are bi-directional but do have a preferred flow direction. It's however strongly recommended to install the valves in the preferred flow direction, as it will extend the valve's life span and will also lower the operating torque.

Keeping this in view, what does a butterfly valve look like?

Butterfly valves use a flat circular disc to control the flow of system product in a piping system. When the edge of the disc faces the system product flow, the valve is in the fully open position. Butterfly valves are also used for throttling. Butterfly valves are classed as quarter turn, straight line valves.

Is a butterfly valve An isolation valve?

Butterfly valves find use only in low pressure and low temperature flow systems. Lightweight and short face-to-face dimension, they can be used both for isolation and regulating the flow of material using their characteristic quarter turn rotating action.

27 Related Question Answers Found

How many types of valves are there?

Learn about 9 Different Types of Valves used in Piping such as Gate Valve, Globe Valve, Check Valve, Plug valve, Ball Valve, Butterfly Valve, Needle Valve, Pinch Valve and Pressure Relief Valve.

What are the two body styles of butterfly valves?

Butterfly Valve Body Types

They are thin, usually taking up much less space in a pipeline than ball valves. The difference in the two main variations of butterfly valves is how they attach to the pipeline. These body styles are lug and wafer style.

How do I know if my butterfly valve is open or closed?

In order to tell if the valve is open or closed, the general rule is, if the handle is switched 90deg to the flow, it is off. As you can see from the diagram above, if the handle is in line with the flow path, it is on. Simple.

Do butterfly valves need gaskets?

Most butterfly valves do not require extra gaskets. All the butterfly valves available on pvcfittingsonline.com for example have built in seals that sit against your flanges and prevent leakage.

What is a high performance butterfly valve?

What is A High Performance Butterfly Valve. High performance butterfly valves can be used for shutoff and throttling control. They are designed to handle everything from general applications to viscous and corrosive liquids; corrosive gases and steam.

What is the difference between gate valve and butterfly valve?

The gate valve is a kind of cut-off valve, which can only be fully open or fully closed, and the flow cannot be adjusted. Butterfly valve, also known as flap valve. Its opening and closing member is a disc-shaped disc which is fixed on the valve stem and rotates around the stem valve shaft to open and close.

How does a gate valve operate?

Gate valves work by inserting a rectangular gate or wedge into the path of a flowing fluid. When fully open, a gate valve has no obstruction in the flow path and so has a very low pressure drop. If the fluid is very viscous a special type of gate valve known as a knife gate valve can be used.

Can butterfly valves be used for throttling?

BUTTERFLY VALVES

They are generally used for handling large flows of gases or liquids, including slurries, but should not be used for throttling for extended periods of time. They are also very compact relative to flanged gate and ball valves.

How many types of butterfly valves are there?

There are 3 main categories of butterfly valves: Rubber-lined, Plastic-lined, and Metal.

Can a butterfly valve be installed backwards?

Can the butterfly valve be installed upside down? The answer is no. The reason is very simple. The butterfly valve can play a sealing role with the valve seat seal and the valve shaft part of the packing.

What is concentric butterfly valve?

concentric butterfly valve: the stem is centered in the middle of the disc and the is disc centered in the bore. the eccentric butterfly valve (double offset and triple offset): have one or more stub shafts (stems) which are located in an offset position from the center of the valve.

What is a resilient seated butterfly valves?

Resilient Seated Butterfly Valves. Bray Resilient Seated Butterfly Valve's seat design and internal disc to stem connection isolates the line media from the body and stem. The seat is designed to seal with slip-on or weld-neck flanges and the molded o-ring eliminates the need for flange gaskets.

What is double offset butterfly valve?

Double Offset Butterfly Valve

This popular valve is also known as a high performance butterfly valve. This valve has two stems offset from the center. This creates a cam action during the application's process. 2^nd offset: The axis of the shaft is eccentric to the center of the valve/pipe line.

What is the seat side of a valve?

Inspect the valve and identify the seat side. The word "SEAT" is cast on the valve body in the chest area on the seat side. Install the valve in the line with the seat side downstream or making sure the flow and pressure is in the direction tending to push the gate against the seat when closed.

How does a disc valve work?

Disc valves (often referred to as eccentric disk valves, or as high-performance butterfly valves) are a variation on the butterfly design intended to improve seat shut-off. The disc's center is offset from the shaft center-line, causing it to approach the seat with a “cam” action that results in high seating pressure.

What is a check valve in plumbing?

Simply put, a check valve allows flow in one direction and automatically prevents back flow (reverse flow) when fluid in the line reverses direction. They are one of the few self-automated valves that do not require assistance to open and close.

What is the symbol for a check valve?

An arrow or the symbol for any type of check valve (a fluidic/pneumatic logic symbol) on the outside of the body indicates flow direction.