A gate valve, also known as a sluice valve, is a valve that opens by lifting a barrier out of the path of the fluid. Gate valves require very little space along the pipe axis and hardly restrict the flow of fluid when the gate is fully opened. The gate faces can be parallel but are most commonly wedge-shaped. Saraswati Steel Gate valves are often operated by handwheel, but they can also be operated remotely using gearing, electric motor actuators, or cylinder (pneumatic or hydraulic) actuators.

Gate valves are used to shut off the flow of liquids rather than for flow regulation. When fully open, the typical gate valve has no obstruction in the flow path, resulting in very low flow resistance. The size of the open flow path generally varies in a nonlinear manner as the gate is moved. This means that the flow rate does not change evenly with stem travel. Depending on the construction, a partially open gate can vibrate from the fluid flow.