At rest, most hydraulic cylinders well, look like a cylinder; named for the hollow cylindrical housing which surrounds their central, mobile piston, which is connected to a hydraulic valve. The hydraulic pressure is standardised across Hi-Force cylinders at 700 bar, higher than some other industries, and serves to raise the central piston from the housing to lift, push or support an object, which rests on the piston’s protective saddle. The function and use are like a common jack but hydraulic cylinders have no internal pump, requiring one to be set up separately to use them, therefore offering more versatility during complex jobs.
Single or Double? Get your action right
The way these cylinders return to a resting position determine their classification as either single-acting or double-acting. You can spot double-acting cylinders by the second hydraulic valve, so you can simply reverse the hydraulic circuit to control the retraction of the piston as you would the raising of it.
Single-acting cylinders have no second valve; instead, an internal spring load helps to collapse the piston. Despite some loss of control, single action cylinder designs are more flexible, allowing for lighter materials such as aluminium, compact sizes and a cheaper product overall. It’s very important to consider the circumstances and get the cylinders appropriate for your job.
Our Hi-Force cylinders are incredibly powerful, with our standard range capable of lifting between 4.5 and 1012 tonnes. When browsing our catalogue the other important dimensions to consider are the cylinder closed height – representing the minimum space required to operate it, the stroke length - the maximum length to which the piston can safely be extruded and of course the lifting capacity in tonnes. Ensure that whatever cylinders you’re looking at purchasing or hiring from Royal Technic will fit your requirements.
Royal Technic carry a range of single- and double-acting Hi-Force cylinders of various heights, from our “pancake” flat cylinders to our versatile, high-stroke-length multi-purpose models. But there are also some specialised models for more particular uses. Hollow-piston cylinders have a hollow piston inside the cylinder housing, allowing the hydraulic force to pull a rod or cable through the cylinder instead. Failsafe Lock Ring models allow for the piston to be locked in place once raised, keeping the load safely in place even if the hydraulics powering the cylinder is disconnected. By contrast, the load-return cylinders commonly used in construction and heavy industry rely on the weight of the load to collapse the piston when required; they have no internal spring or mechanism and are exclusively single-acting.
These various features and dimensions combine to produce a huge variety of cylinders which Royal Technic make available for purchase or hire, along with our range of jacks, pumps, and related hydraulic equipment. We can even make custom cylinders to order, building them to match the needs of your job. On the other hand, if you’re not sure which model you need specifically, no stress, just describe your job to us and we’ll work with you to make up an order of cylinders to get it done.