Like all butterfly valves, stainless steel butterfly valves consist of a seal around a pipe wall, a round disc or plate and a control lever.
The body and disc of stainless steel butterfly valves are made of stainless steel materials. Stainless steel is a metal that is resistant to corrosion and oxidation. It is chosen over other metals and traditional steel because it has a longer life and requires less maintenance. Stainless steel is also highly sanitary and easy to clean. Being sanitary means it is one of the few metal butterfly valves that can be used in food and medical related piping systems.
The other common metal material used by butterfly valve manufacturers is cast iron. This material is strong and durable, often found in the same sorts of environments stainless steel is found. However, it can not be used to produce the gasket part, because it is not flexible or light enough, so stainless steel or aluminum are employed instead. Plastic butterfly valves are not as popular as cast iron and stainless steel, because even though it is less expensive it is not as resistant to chemical corrosion as metal and therefore is more of a risk.
Operators of stainless steel butterfly valves can control the flow of a fluid or gas by pulling a lever that opens or closes the valve. When the disc is parallel to the flow of water, the valve is in open position and lets all gases or liquids pass; when the handle is turned, the disc rotates around to a position parallel to the flow of water.
It fits snugly into the seal and blocks all flow through the pipe. The design of butterfly valves has advanced in recent years, partly due to the needs of a larger variety of piping systems in multiple industries that have developed. It is also because the machining techniques, such as CNC machining, now allows manufacturers to create precise fits for any type of pipe or tube. Stainless steel butterfly valves are an efficient and reasonably inexpensive type of flow control device. They are used in water distribution, chemical services, and in ventilation applications.