How are gate valves primarily operated?

Gate valves are primarily operated by turning a wheel. This wheel is connected to a stem that moves a gate (a wedge-shaped piece) up and down within the valve body to control the flow of fluid. When the wheel is turned in one direction, it raises the gate, allowing fluid to flow through the valve; turning the wheel in the opposite direction lowers the gate, closing the valve and stopping the flow.

The design of the gate valve allows for minimal pressure drop when the valve is fully open and provides a reliable sealing capability when in the closed position. This mechanism is particularly effective for on/off control in piping systems, making the wheel operation an appropriate feature for managing flow efficiently.

Other operational methods, such as knobs or levers, may not provide the necessary mechanical advantage or precision for the effective control required in gate valves, which is why turning a wheel is the standard operation method in this context.