Hydraulic orbital motors use a gerotor to convert the flow and pressure of hydraulic fluid into low speed, high torque, (LSHT) rotary motion. They’re used in a wide range of mobile equipment and industrial applications, from sweepers and scissor lifts to conveyors and mixers.

Perhaps you’ve considered and discounted them in the past. Perhaps you are looking for a LSHT motion solution for the first time, or maybe you just want to know what new capabilities are available. Whichever group you fall into, here’s what you should know about the recent innovations and advances.

Three Areas of Innovation

Hydraulic orbital motors are rugged and reliable: their design and engineering has been honed over decades of field service so they perform exactly as expected, with no surprises. The companies that use them in their products compete in tough markets though, and they need motors that incorporate the latest technology so they can offer higher performance.

The top three things happening in hydraulic orbital motor engineering today are:

• Advanced materials
• Smart sensors
• Digital controllers

Here’s a closer look.

Advanced Materials

Aspects impacted by material technologies are:

• Gears: Higher strength and more wear-resistant steels for lighter and more durable assemblies. Also, wear-resistant coatings on rotor and stator teeth profiles.
• Seals: Adopting new and improved polymers, elastomers and, where appropriate, PTFE (Teflon) materials for longer life.
• Housings: Lightweight alloys and composites (particularly fiber-reinforced plastics) are under investigation as a way of reducing motor weight (a priority in mobile applications).

Smart Sensors

Sensors that provide information about what is happening inside the motor can help extend its life and provide more precise control over operation. Sensors under consideration and being implemented include those for:

• Speed
• Temperature
• Shaft position
• Vibration
• Pressure and load

“Smart” sensors are those with signal processing capabilities. They could perform averaging, apply filters, or send alerts only when certain threshold conditions are exceeded. Smart sensors with communications capabilities – WiFi, cellular, Ethernet, Profibus and others – form the basis of Industrial Internet of Things (IIoT) Industry 4.0 technology.

An emerging application area is predictive maintenance. This is where the motor can signal when wear or other problems are approaching a point where the risk of failure is rising. Temperature and vibration sensing are especially useful in this kind of role. A predictive maintenance system, often powered by AI, can use this data to raise Work Orders for inspection, servicing or replacement.

Digital Controllers

Sensor data enables advanced digital controllers to better optimize motor operation. Current and future capabilities include:

• Load sensing and adaptive control: The controller could adjust a valve position or signal the hydraulic pump to run faster or slower to maintain motor speed and output torque at the required levels.
• Remote monitoring and predictive maintenance: Mobile equipment, like that used in agriculture, forestry and construction, could signal when a problem is being sensed, so a new motor can be ordered and replacement scheduled.
• Higher precision speed and torque control: This can improve low speed operation and increase smoothness, both of which can contribute to higher safety and improved ease of use.

Explore the Benefits for Your Applications

Hydraulic orbital motor technology is advancing in ways that makes them more durable and reliable, lighter, and easier to use. If you’ve previously had concerns about their life or suitability in particular applications, these innovations may have changed the scope of what’s possible. If you’re engineering a new mobile or static application for LSHT rotary motion, they may open up possibilities you hadn’t considered before. Contact us to discuss your application and learn more.