Gate valves are a type of valve used to control the flow of fluids through a piping system. They are designed to provide a tight shut-off by sealing against the seat to prevent fluid leakage when closed.

Gate valves are typically operated by rotating a handle or wheel that turns a threaded stem connected to the gate. The gate is a flat or wedge-shaped component that slides into the flow path to control the flow of fluid. When the valve is open, the gate is lifted out of the flow path, allowing fluid to pass through the valve unimpeded. When the valve is closed, the gate is lowered into the flow path, blocking the flow of fluid.

Gate valves are commonly used in applications where full flow is required, such as in the oil and gas, chemical, and power generation industries. They are available in a variety of materials, including cast iron, cast steel, stainless steel, and alloy steel, and can be designed for both standard and high-pressure applications.

One advantage of gate valves is their ability to provide a tight shut-off, even in high-pressure and high-temperature applications. They are also relatively simple in design and can be operated with a simple handwheel or gearbox.