Single Acting Vs Double Acting Hydraulics

If you think of an aeroplane as a complete puzzle board, and all the parts that make up that aeroplane are pieces to the puzzle – eight years of studying Mechanical Engineering sounds like a fun rainy day activity.

If only it were that simple.

In a world of increased reliance on complex powered machinery, single acting and double acting hydraulic cylinders are seen to be a fundamental piece of the domestic and industrial machinery puzzle. A source of strength and power throughout many of the world’s heavy lifters — from bulldozers to aeroplanes, wheel jacks to brakes, hydraulic cylinders are fundamental to keeping us powered and moving.

Sounds rather complicated, right? In actual fact, the mechanics behind hydraulic cylinders is actually rather simple. In this blog, we explore the differences between single and double acting cylinders and share some of the advantages that they each possess.

Single Acting Hydraulics

Single acting cylinders are the simpler of the two and extend through pressure from the pump and retract with the help of an inbuilt spring or under the weight of the load.

Because they are simpler in design, single acting hydraulics are much easier to use and maintain. The hydraulic fluid performs on just one side of the piston in a single-acting cylinder, and since the hydraulic oil does not compress, the piston rod of the cylinder will only extend. More specifically, the pump forces oil into the hose which then flows into the bottom port of the cylinder, resulting in the ability for pushing, jacking, and tensioning applications.

Simplicity is always sought after for equipment that is required to be rugged and reliable. Therefore single acting hydraulics are a reliable choice for elementary tasks such as lifting in one direction like a car jack for example.

Double Acting Hydraulics

Double-acting hydraulics, however, perform on both sides of the piston. With two connection ports on the pump and cylinder; one at the bottom portion, the other at the top portion of the cylinder body – this system requires hoses for each port.

This allows the cylinder to create extend and retract forces that move the piston rod and allows for more control over a desired movement in two directions. Double-acting cylinders are commonly used in heavy industrial and construction industries, such as lifting bridges.

Contact Motus Today

Knowing the difference between a single and double acting cylinder is important when considering the kind of equipment or machinery that will be running and operating – no matter what the application may be.

Motus has been trusted for its commitment to understand the needs of our diverse range of valued customers.

Get in touch with Motus if you’re searching for the ideal single or double acting ram, or any other hydraulic system for domestic or industrial use. We’ll have you fitted with state-of-the-art technology and service to match.


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