The butterfly valve is a pressure-controlled valve equipped with a balanced pivoting disc that opens and closes like the wings of a butterfly. These valves are available in two main designs: Unbalanced Butterfly Valve and Balanced Butterfly Valve. Both have their own benefits and applications, but for most industrial water systems, the Balanced Butterfly Valve is the better choice. Unbalanced butterfly valves are used when flow needs to be controlled on either side of the valve. They are also known as Double Check or Double-Ended Valves. Their main disadvantage is that they can only control one direction of flow at a time, requiring an unbalanced valve on both sides if bidirectional control is needed. The butterfly valves we’ll look at here are examples of the balanced type, which are beneficial because they allow you to control both ends of the valve from either side while maintaining equal pressure on each side of the valve regardless of its position.

A solenoid valve is an electrical valve with an integrated solenoid. It uses electromagnetic force to control the flow of fluids in industrial processes and other applications.
A solenoid valve is a type of fluid control valve that uses electro-mechanical principles to open or close ports on demand. They are either normally closed or normally open valves, but not both at once. Solenoid valves are differentiated by the way electricity powers them: continuous current vs. alternating current, as well as NC (normally closed) vs. NO (normally open) configurations.
Here we discuss types, functions, operating principle and applications of a solenoid valve in detail.