A ball valve is a valve that opens by the turn of a handle, gearbox or other actuation method attached to a ball, the part of the valve which controls the flow through it. The ball has a hole, or port, through the middle so that when the port is in line with both ends of the valve, flow will occur. When the valve is closed, the hole is perpendicular to the ends of the valve, and flow is blocked. The handle or lever will be inline with the port position letting you "see" the valves position. Position indicators will be applied to a gearbox or actuator as required. The ball valves, along with the butterfly valve and plug valve, are part of the family called quarter turn valves.

Ball valves are durable and usually work to achieve perfect shutoff even after years of disuse. They are therefore an excellent choice for shutoff applications. There are two type of ball valves based on the ball type, floating ball valves and trunnion mounted ball valves. Depending on the bore size of the