Standard & knife gate valves
Gate valves, or sluice valves as they are otherwise referred, shut off by the valve element being lowered into the flow. This mechanism provides tight seal in shut off position, but is vibration-sensitive in open position making the gate valve not ideal for throttling. Sluice valves benefit from a lower pressure drop than a globe valve as the element fully retracts into the bonnet. They are also more economical, but are more prone to leaks due to greater wearing.