What is the difference between lug type and wafer type butterfly valve?

Typically there are 8 or 12 lugs where 4 or 6 lugs are used to connect the each pipe section. Wafer type valves don’t have attachment lugs, though them may have alignment lugs. They are sandwiched between the flanges on the ends two lengths of pipe. To replace either length of pipe requires shutting the system down.

What is a wafer butterfly valve?

Wafer-Style Butterfly Valve The valve is designed to clamp between two flanges in your pipe work. Most wafer butterfly valves fit the majority of flange standards. The rubber or EPDM valve seat creates an exceptionally strong seal between the valve and flange connection.

What is a wafer flange?

Wafer type The flange bolts are inserted through the bolt holes of the two pipe flanges and the centering holes of the butterfly valve. By tightening the flange bolts, the pipe flanges are pulled towards each other and the butterfly valve is clamped between the flanges and held in place.

What must be done to the wafer lug butterfly valve itself just prior to installation?

The installation of the wafer butterfly valve must be laid flat before installation, remember not to bump it at will, after it is drawn to the installation length during installation, in the design of the on-site pipeline, it is not possible without special permission Disassemble the wafer butterfly valve at will, this …

Does a butterfly valve need a gasket?

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.

Do wafer butterfly valves need gaskets?

Even wafer style valves require 2 flanges. These should be the same size as your valve and may be one piece or loose ring style flanges. This will allow the surrounding pipe line to connect snugly with the butterfly valve. Most butterfly valves do not require extra gaskets.

What is a wafer connection?

Wafer Connection. In a wafer connection the valve is installed between the pipe flanges and tightened to its place with the bolts for the pipe flanges. In some wafer types there are some centering holes on the body to ensure valve’s correct position between the flanges.

How does a butterfly valve seal?

A butterfly valve is a quick opening, rotational motion valve that uses a metal, circular disc (vane) to start, stop or regulate flow in a pipe. Typically, a simple 90° rotation of the valves handle either opens or completely closes the valve as the vane seals itself against the seats in the valve housing.

Does it matter which way you install a butterfly valve?

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.

Can you install a butterfly valve upside down?

The medium will flow to the filler to erode the filler if the butterfly valve is installed upside down. It would destroy the sealing performance and cause the leakage of the valve. The leakage of poisonous and harmful medium will cause safety risks and system damage.