Butterfly valves provide lightweight and low-cost control over water flow in fire sprinkler and standpipe systems
A butterfly valve isolates or regulates the flow of fluid through piping systems. While they can be used with liquids, gases, and even semi-solids, butterfly valves for fire protection serve as control valves that turn on or shut off the flow of water to the pipes serving fire sprinkler or standpipe systems.
How does a butterfly valve work?
A butterfly valve for fire protection starts, stops, or throttles the flow of water via the rotation of an internal disc. When the disc is turned parallel to the flow, water can pass through freely. Rotate the disc 90 degrees, and the movement of water into the system piping stops. This thin disc can stay in the water’s path at all times without significantly slowing the movement of water through the valve.
The disc’s rotation is controlled by a handwheel. The handwheel rotates a rod or stem, which turns the disc and simultaneously rotates a position indicator — usually a brightly colored piece sticking out of the valve — that shows the operator which way the disc is facing. This indicator allows for at-a-glance confirmation of whether the valve is opened or closed.
The position indicator plays an important role in keeping fire protection systems operational. Butterfly valves serve as control valves capable of shutting off the water to fire sprinkler or standpipe systems or sections of them. Entire buildings can be left defenseless when a control valve is unintentionally left closed. The position indicator helps fire professionals and facility managers spot a closed valve and re-open it quickly