Gate valves are primarily designed for on-off services when a straight-line flow
of fluid and minimum restriction is desired. The closure member of gate valves
either stops or allows flow through the valve and acts somewhat like the opening
or closing of a gate and is called, appropriately, the gate valve.
The gate is also shown as a wedge, due to the shape is resembles. When the valve
is open, the closure member is fully drawn up into the valve, leaving a complete
opening for the flow stream. Therefore, there is little pressure drop or flow restriction
through the valve. Gate valves are used in many industrial applications including
the oil and gas industry, pharmaceuticals, manufacturing, automotive, and marine.
Gate valves are not suitable for throttling purposes.