What is the difference between a single-acting and double-acting hydraulic cylinder?

A single-acting hydraulic cylinder is designed to apply force in one direction, utilizing hydraulic pressure to extend. When fluid enters the cylinder, it moves the piston, allowing it to perform work such as lifting or pushing an object. The return motion of a single-acting cylinder typically relies on a spring or gravity, leading to the characteristic that it provides power in only one direction.

This design contrasts with double-acting cylinders, which can apply force in both extending and retracting movements by using hydraulic pressure on both sides of the piston. Therefore, the primary distinction lies in the operating mechanism: single-acting cylinders work unidirectionally while double-acting cylinders operate bidirectionally.

In terms of functionality, this makes single-acting cylinders suitable for applications where the return stroke can be achieved by other means, whereas double-acting cylinders are often used in scenarios requiring more control and power in both directions.