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

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

Lug type valve as the name suggests has lugs that are used to mount the valve to lugs that are attached the flanges on then ends of sections of pipe so that each length of pipe can be removed and replaced independently. Wafer type valves don’t have attachment lugs, though them may have alignment lugs.

What is wafer butterfly valve?

The wafer style butterfly valve is designed to maintain a seal against bi-directional pressure differential to prevent any backflow in systems designed for unidirectional flow.

What are the different types of butterfly valves?

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

What are the two body styles of butterfly valves?

Butterfly Valve Body Types Butterfly valves are popular because of their low-profile designs. 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.

What is wafer type and lug type?

Wafer-Style Butterfly Valve Most wafer-style butterfly valves are engineered with four holes that align with the connected pipeline. The valve is designed to clamp between two flanges in your pipe work. Unlike lug-style butterfly valves, wafer-style butterfly valves cannot be used as pipe ends or end-of-line service.

Do wafer butterfly valves need gaskets?

Even wafer style valves require 2 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 lug on a valve?

Lug. Has bolt holes to connect with pipe flanges. Because it has threaded bolts around the entire area, the lug valve is a safer option—most customers can switch from a wafer valve to a lug valve; however, they cannot switch from a lug to a wafer. Lugs can be used as a pipe ends or as end-of-line service.

What is wafer type?

Wafer type In the case of a Wafer-style butterfly valve, the body is annular with a few non-tapped centring holes. Some Wafer types have two while others have four. The flange bolts are inserted through the bolt holes of the two pipe flanges and the centering holes of the butterfly valve.

What does wafer type mean?

In a wafer connection the valve is installed between the pipe flanges and tightened to its place with the bolts for the pipe flanges. Wafer type body is the lightest body version for mounting between piping flanges. Therefore a wafer valve use to be cheaper than other valves. Also it is fast mounting.

Does it matter which way a butterfly valve is installed?

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.

Do butterfly valves have a flow direction?