·Manual valve: A valve operated by human power with the help of hand wheel, handle lever or sprocket. When larger torque is required, reduction devices such as worm gears and gears can be used.
·Electric valve: A valve operated by electromagnetic motor or other electrical device.
Hydraulic or pneumatic valve: a valve controlled by the pressure of liquid (water, oil and other liquid media) or air
Linkage valves: mainly composed of gas-liquid linkage valves, electric-hydraulic linkage valves, etc.
