Difference between wafer butterfly valve and lug b|emerson v

Difference between wafer butterfly valve and lug butterfly valve

Home
/ News
/ Industrial News
/ Difference between wafer butterfly valve and lug butterfly valve

Difference between wafer butterfly valve and lug butterfly valve

Feb.20.2025

Butterfly valves are quarter-turn valves used to control the flow of product in pipelines. From pharmaceuticals to manufacturing and food processing, the valve can be used to restrict the flow of solid, liquid or gaseous materials in a variety of applications. Butterfly valves are generally divided into two types: lug and wafer. These mechanical parts are not interchangeable and have unique advantages and applications. The following explains the differences between the two butterfly valve types and how to choose the right valve for your needs.

The technique of installation is the primary distinction between a wafer butterfly valve and a lug butterfly valve. A wafer butterfly valve is installed between two flanges, whereas a lug butterfly valve is installed on each side independently of the flanges.

Lug style butterfly valves are usually made of metal such as ductile iron or steel. They have threaded lugs on the valve flange for bolting. Lug style butterfly valves are suitable for end-of-line service, but blind flanges are always recommended. Lug style butterfly valves are manufactured to be compatible with pneumatic or electric actuation. Disc and seat materials should be determined according to the application and flow medium. Most wafer butterfly valve designs have four holes that line up with the connecting pipe. The valve is designed to grip two flanges in a pipeline.

Most wafer butterfly valves conform to most flange standards. A rubber or EPDM seat creates an extremely strong seal between the valve and flange connection. Unlike lug butterfly valves, wafer butterfly valves cannot be used as end-of-pipe or end-of-line. If maintenance is required on either side of the valve, the entire line must be shut off. Wafer butterfly valves shall be manufactured to be compatible with pneumatic or electric actuation. Disc and seat materials should be determined according to the application and flow medium.