Smart Actuator: material science in polymer design
In 2017 the Smart Actuator Company won a British Queen’s Award for Enterprise in Innovation. The company, based in the Midlands (United Kingdom), has been active - amongst other domains (smart electronics) -in the field of material science and application, for example in the use of polymer parts.
^ “A series of internal gears is used inside SmartAct Actuators that produce the final output torque and drive. The exact design and how the gears are in position cannot be disclosed due to our patent.”
Article by Lucien Joppen
Smart Actuator is focussing on electric actuators, which are used worldwide in various sectors. As a result, these products need to be robust and reliable, being able to cope with a variety of climates and processing conditions.
According to the company, its products are installed in various production locations such as subsea, offshore rigs, submerged pipelines, food processing plants, waste management facilities, water purification plants, zoos/public attractions and fire suppression systems. Within all these locations the company ensures that SmartAct Actuators are intrinsically safe as directed by SIL Standards (currently Self-Certified to level 2 of 4). Finally, the company prides itself on having produced an electric actuator being able to deliver a “massive 75% energy saving over other traditional electric actuators.”
Smart Actuator Company has opted for polymer parts for its small and medium actuators. The company’s Managing Director James O’Donnell is the force behind this development. He has consulted with a materials expert from an injection moulding company for advice on specific Nylon-polymer blends to fit his requirements. The injection moulding company has tested different blends for the parts submitted to Smart Actuator Company to be assembled and tested before the final compositions were selected.
These parts (the internal worm, worm wheel, centre gear, handle, internal walls and plates) are partly moulded from a Nylon 66 compound, a ‘cousin’ of Kevlar which has similar properties to mild steel. Nylon 66 has approximately 40% Glass Fibre content that gives it structural stability and robustness. This compound has been used for aerospace projects, military uses such as armoured plating both for vehicles and personnel, and many more applications that require high-performance compositions.
The benefits for using Nylon 66, compared with metal-based parts, are: lighter in weight, a faster manufacturing time, no single-use (recyclable), extremely robust and durable, more cost-effective and corrosion-free.
Built-in magnifying glass
The lid of the actuator is moulded from Nylon 12, which has similar characteristics to Nylon 66. The Nylon 12 was used for the lid after consultation with the injection moulding expert as it still retains the hydrophobic qualities required for IP67 (similar to Nylon 66) while allowing it to be translucent.
The latter property allows customers to see the internal workings of the actuator; it also helps when checking the relevant degree angle that the actuator has turned. The lid also has a magnifying glass built in to aid the degree angle view.
Apart from Nylon 66 and 12, Smart Actuator has applied Delrin 500 and Acetal for its internal parts. Delrin 500 gives a smooth surface structure, and the Acetal (a Molybdenum/PTFE-make-up) provides extra stability whilst allowing some flexing in the Actuator movements. The benefits of using an Acetal/Molybdenum/PTFE-combination for gears are: self-lubrication, a longer life cycle, lighter in weight, faster manufacturing times, more cost-effective, many colour options available and corrosion-free.
Polymers or polymer blends also offer advantages as these materials can be recycled, either mechanically or chemically. All the polymers that are used can be ground up and used again. James O’Donnell, Managing Director: “They will not degrade so in use will last a long time. However, should they need to be disposed of here at SmartAct, we will happily strip the actuators down and send all the plastic polymer parts back to the injection moulding company we use.
Our commitment to saving the world through energy-saving extends to having a generally great environmental ethos in our products from materials to recyclable packaging.”
“Our customers appreciate the sustainability factor of our robust, durable materials and our commitment keeping manufacturing cost low, and using smart technologies and - as mentioned before – the energy-saving capacity of our product range.”
The company’s distributor in India has just received its first consignment of Medium SmartAct Actuators and immediately responded with this testimonial. “We have successfully tested one of 40Nm Actuator. It was an awesome experience for us to use this type of Smart Actuator for the first time. It is really smart as it is simple to operate”.