Butterfly Valves are easy and quick to open. A right angle rotation of the handle provides a complete closure or opening of the butterfly valve. Large Butterfly Valves are usually comprised of a gearbox, where the hand wheel by gears is joined to the stem. This gives ease to the operation of the Butterfly Valve, but at the expense of speed.Smit Valves have a short circular body, soft seats, shaft bearings, and a stuffing box. The construction of a Butterfly valve body varies in design. A mostly used design is the wafer type that fits between two flanges. The lug wafer design is another common design that joins the two flanges and passes through the holes. Butterfly valves are even available with threads that are flange and have butt welding ends, but they are not used often. Butterfly valves comprises of advantages like over gate, globe, plug, and ball valves. These advantages are especially for large valve applications. The best and obvious advantages are saving of weight, space and cost. The maintenance costs are generally down because there is less number of mobile parts and there are no pockets to store fluids.Valves are especially well for the handling of large flows of liquids or gases.
Valves are built on the principle of a pipe damper. The flow control component is a disk of approximately the same diameter of the adjoining pipe, which rotates on either vertically or horizontally. When the disk lies collateral to the piping run, the butterfly valve is fully opened. When the disk approaches the 90 degree angle, the valve is shut.