There is a wide variety of pneumatic products on the market that nicely suits almost any industrial purpose. But, in some cases, a hydraulic cable linear actuator may be the better choice.
All linear actuators convert energy into straight-line motion, forward and/or back. Hydraulic actuators use fluid as a power source rather than compressed air, and they use either a rod or a cable to move the load. Each type has advantages and limitations, so the key to successful performance is matching the cylinder with the task at hand. Let’s look at the differences between these two types of hydraulic actuators.
Why Hydraulic Power Instead of Pneumatic?
Typically, hydraulic pressure sources create higher forces than does an air pressure source so if your application requires a force output greater than what say, 200 PSI can produce, then you may want to look at using hydraulic pressure. So, if you need a lot of power, you’ll want a hydraulic actuator. Hydraulic power tends to provide smooth, consistent motion along the entire stroke, which can be crucial in some applications.
Why Cable Instead of Rod?
A cable is an interesting mechanism. It functions much like the tendons in your body, which enable muscles and joints to create remote motion efficiently. With limited torque at the power source, the tendons can produce large or small movements, repeatedly and rapidly. Thanks to tendons, your forearm can flex and span your fingers with minimal effort.
A hydraulic cable linear actuator is, well, linear, so it can’t drive complex motions such as operating your hand (or a multi-movement industrial task) all by itself. But it does offer remote actuation, along with other unique benefits:
- If your application requires a stroke length greater than 24 inches but the operating envelope is compact because of space limitations (a common challenge), a cable cylinder is a much better choice than a rod cylinder. That’s because cable cylinders move their stroke over the body of the cylinder, whereas rod cylinders move their stroke outside the body.
- If your application requires a higher stroke length, cable cylinders are once again the better choice compared to a rod cylinder. Cable cylinders can achieve a stroke length over 20 feet, whereas a rod cylinder can typically only deliver a stroke up to 2 to 3 feet.
- Also, a braking option can be added to a hydraulic cable linear actuator that would assist with stopping and position hold of workload.
We do want to note that hydraulic rod cylinders can achieve higher force than a hydraulic cable linear actuator because you can run them at a higher pressure. Hydraulic rod cylinders can be rated up to 1,000–2,000 psi, while cable cylinders can generate only about 500 psi.
Is a hydraulic cable linear actuator the right choice for your application? Maybe. Or maybe there’s a pneumatic actuator that would serve you just as well. We’re always happy to help customers puzzle through knotty problems, so give us a call if you aren’t sure which product to spec.