A gate valve is designed to turn the flow of liquid through pipes on and off. It is generally used on a valve that is not used frequently. It is also helpful in controlling the flow of pressure through the pipes and valves. Also known as a sluice valve, it controls flow by moving a round or rectangular wedge in and out of the liquid path.
Gate valves most commonly come in two varieties. The parallel gate valve uses a flat disc to shut off and control the fluid pressure. It creates a seal to prevent leakage. Parallel gate valves also have two types: knife valves and through-conduits. The knife valve has a sharp bottom to cut through any solids passing through the pipe. The through-conduit is rectangle shaped with a circular opening to allow fluid to flow when it is lowered.
Wedge-shaped gate valves allow for the fluid to be tightly shut off and come in three separate designs. The split wedge allows for disk flexibility. This flexibility helps the valve to seal easily. Solid wedges are simple and strong. They are the most common valve because they are suitable for almost every situation. Flexible wedge valves are mostly used for steam systems and are available in a variety of different sizes and shapes.