All-in-one Linear Actuator
All-in-one linear actuator technology delivers energy and cost savigs for UK manufacturers.
A revolution is taking place in actuated systems to deliver the combination of vastly simplified system design and significant energy savings. Roller screw driven actuators hold the key.
Many industries are finding that, in particular applications, there are good reasons to move away from either hydraulic or pneumatic linear actuation technology. The problem is that there hasn’t always been a viable electric alternative. Plenty of solutions are discussed, but by the time you’ve considered the headache of integrating the drive, ballscrew, coupling and motor of a traditional system, the operational and maintenance benefits seem to look a little far away.
There is no doubting the energy saving potential of electrical systems, and this is key at a time when energy efficiency is high on the list of priorities for most businesses. It’s not hard to see why electric linear actuators could be rapidly taking over from more traditional hydraulic and pneumatic actuators. But perhaps if there was an all-in-one electrical option, that transition might progress a little more quickly.
Well, there is, in the form of the latest high precision roller screw electric actuators from Olsen Engineering. The new 230V Exlar Tritex II offers a host of benefits in that the single enclosure contains not only a high precision inverted roller screw actuator but also the brushless servo motor, servo amplifier and position controller. This eliminates the unreliable multiple connections necessary between the components of other typical servo linear actuators making the Tritex II literally a plug-and-play unit.
In response to customer demand, the new 230V version takes the all-in-one concept to a new level eliminating the need for a 48V power supply, still common among many other actuators. The position control function has been enhanced allowing up to 16 positions to be programmed. There is an integrated load cell option. The incremental encoder offers 8192 count accuracy and anabsolute encoder option is planned along with a number of bus options. Also included is flash upgrade of the firmware via a Modbus port allowing new features to be added in the field. An LED display indicates power, status and two customer programmable indicators. Initially 90mm and 115mm frame size units are available offering linear speeds up to 1072mm/s and linear force up to 16.4kN, but larger frame sizes are in development.
“The biggest challenge is demonstrate to users what the latest electrical actuators can do – to give them a real reason to take the radical step of changing their hydraulic or pneumatic specifications,” says Olsen Engineering managing director Piers Olsen. “We’ve seen specifications for valve actuators in the process industry that have stayed unchanged for 30 or 40 years. That can make a change to electrical actuation seem like a daunting step.But it doesn’t have to be. With these all-in-one actuators offering the performance of pneumatic or hydraulic alternatives but without the integration headaches of traditional electrical actuators, we’ve got a virtual drop-in replacement.”
The scope of the new Exlar products goes well beyond valve actuation in the process industries, of course. There are numerous military applications that call for robust and reliable linear actuations, and Olsen Engineering has also had notable successes in the food and beverage industry. Here in particular, the need for energy efficiency, reliability and cleanliness is driving many large manufacturers to demand fully electrical machines and move away from hydraulic and pneumatic actuators. “If you look at something like a food processing line, or bottle capping or sealing line, operations such as pushing on the caps have traditionally been pneumatic,” says Olsen. “But by providing an electrical alternative that can offer the same high forces and the same high speeds in a really compact package, we can offer significant benefits.”
The slightly higher first cost of the electric actuator is very rapidly offset by the energy savings. The electric unit, better than 85% efficient, uses energy only when actually in operation. By contrast, pneumatic units require a constant air supply and compressor systems are notoriously noisy and inefficient. The infrastructure costs of hydraulic and pneumatic systems are also extensive and entail high maintenance as well as running costs. This is dictating the choice of electrical actuators especially for new plant on Greenfield sites.
The new 230V range of Tritex II actuators makes it even easier to adopt clean, reliable, programmable electric technology in place of inefficient air and oil driven alternatives.