Piston type. A single piston rod hydraulic cylinder has only one end of the piston rod. Both ends of the inlet and outlet oil A and B can pass through the pressure oil or oil return to achieve two-way motion, so it is called double acting cylinder. The pistons can only move one way, and the opposite direction needs to be done by an external force.

Plunger type. Plunger hydraulic cylinder is a single acting hydraulic cylinder, which can only achieve movement in one direction by liquid pressure. The plunger is only supported by the cylinder sleeve but not in contact with the cylinder sleeve, so the cylinder sleeve is easy to be processed, so it is suitable for long stroke hydraulic cylinder. The plunger is always under pressure at work, so it must have sufficient stiffness. The plunger weight is often large, and it is prone to sag due to dead weight when placed horizontally, resulting in sealing and guiding unilateral wear, so it is more advantageous to use vertically. The pistons can only move one way, and the opposite direction needs to be done by an external force. But its stroke is generally larger than the piston hydraulic cylinder.

Telescopic type. The telescopic hydraulic cylinder has two or more levels of piston, the piston in the telescopic hydraulic cylinder extends from large to small, and the order of no-load retraction is generally from small to large. The telescopic cylinder can achieve a longer stroke, while the length of retraction is shorter and the structure is more compact. This kind of hydraulic cylinder is often used in construction machinery and agricultural machinery. The output speed and output force of each piston are variable when it moves one time to another.