Water is a problem in many industrial processing situations. Conveyors and other materials handling systems, for example, can malfunction if too much water is to spill on them.
However, companies that continually process and pack wet products must frequently wash down their machines to ensure the proper sanitary conditions.
This is especially important for the processing of meat and dairy products, for example, or the production of food and beverage, wine and beer or low-margin high-volume products where product recalls or production breakdowns could be catastrophic. In these situations, pneumatics can be a smart option to decrease downtime, lower maintenance costs, and, ultimately, increase production.
"Pneumatics offer many advantages over hydraulics for some such applications. With minimal contamination risks, pneumatics is a clean technology and a first choice for food and packaging companies," said James Maslin, a specifier from Air Springs Supply.
"Because fewer moving parts are nearly always better than more, one excellent solution for simplicity and reliability can be to employ actuators without seals, shafts or internal moving parts."
Air Springs' enormously tough rubber and fabric-reinforced actuators are, in effect, balloons or bellows engineered to particular shapes for particular tasks. The single, double and triple-convoluted and rolling sleeve Airstroke designs are made to the same rigorous standards as the air springs used as suspension springs in heavy vehicles such as semi-trailers, where they have to withstand monumental battering year in, year out.
The range available to manufacturers and processors throughout Australia extends from the largest, 40,000kg capacity, models down to palm-sized Airomatic mini actuators for delicate jobs requiring a clean actuator that doesn't need lubrication and can cope effortlessly with high-repetition tasks. Eliminating lubrication eliminates another sticky surface for waste adherence.
"And another of the beauties of this form of actuation is the inherent flexibility of the actuators when they meet their working surface," Maslin said.
"Being made of rubber and not having any rods or seals to damage, they can bend or flex to the surface of the belt or conveyor section. Their flexibility also makes them ideal for applications such as belt take-ups or roller friction applications, where they may be applied against an oscillating surface.
"They can also stroke through a radius without a clevis, thus eliminating both complexity and cost when you need to actuate through an angle. Their ability to soak up shock without damage while delivering high-repetition strokes means they are highly applicable to conveyor transfer, gate and lift sections."
Another plus of Air Springs Supply's Airstroke range is that it can fit into the tight spaces frequently encountered in food and beverage and primary processing plants. The range offers actuation strokes ranging from 12.5mm for the tiny (16mm high deflated) new Airomatics, through to more than 300mm for triple-convoluted models used as both actuators and isolators. These collapse (deflate) to a fraction of their inflated height, for compact installation.
Choosing actuation technology
Choosing the wrong technology can have negative effects on production: in a wet environment, oil leaking on a polished tile floor is a real safety hazard.
Using air spring pneumatics — particularly for washdown and sanitary food applications — offers a built-in advantage because of the low maintenance costs and low downtime associated with the technology.
"High volume food and beverage industries can't afford to have downtime on a production line, because customers expect deliveries on time every day 24/7," Maslin said.
Many high volume businesses survive on very low margins. If they have high maintenance costs for keeping a piece of equipment going, that comes straight off the bottom line. So maintenance cost is critical — and one of the beauties of air spring pneumatics is that it's easy to troubleshoot and to detect problems without downtime being an issue. Simplicity is once again a big advantage.
"Air spring pneumatic products are a great choice for the food and primary processing industry because they withstand even the toughest environments — we have them installed in mines and quarries, where they stand up to a huge trashing and very dirty environments with a longer life expectancy due to their simple design and absence of internal components to wear or break.
"In addition, the systems are easy to design and the components are easy to configure."
Selecting pneumatic equipment
No matter what equipment is chosen, the key points to remember are it must be easy to clean and maintain, says Maslin. Because they are cost-effective and easy to maintain, air spring pneumatics are ideal for applications where wash-down is a consideration. When using air spring pneumatics in such applications, it is important to:
Select the right product for each application — various products suit different needs:
- Decentralise valve manifolds on larger production lines;
- Dimension pneumatic systems for optimal performance;
- Ensure the air pressure is constant to maintain optimal actuator performance by placing the regulators close to the actuators;
- Involve your technology supplier from the beginning of the project to get the correct solutions for each application.
Maslin says a pneumatics system can be substantially cheaper than a mechanical system: "The savings extend throughout the production life cycle because the airbag actuator system is so user-friendly.
"The sheer muscle and speed of pneumatics — an air cylinder is basically a fast-acting mechanical muscle — allows you to do so much with it and makes it so easy to use and control. The technology is thoroughly proven to be very reliable.
Maslin concluded: "We don't say for a moment that Airstrokes are the ideal solution for all actuation needs, because every professional knows that each case needs to be considered on its own special needs — but we do know from a generation of experience that they can save a lot of time and money over a vast range of applications, because we have installations that have completed millions upon millions of cycles with outstanding reliability."