Machine efficiency can come from many directions. It might mean using better drives, servo motors and robots. Even bigger gains might be possible by redesigning machines and operations to use fewer materials and produce more sustainable products.
This is why true efficiency in the building and operating of your machines is about more than on/off and how many units are produced. It means taking a deeper, more detailed look at how energy and equipment are procured and used — which at its heart is really nothing new — or shouldn't be. Likewise, sustainability in manufacturing begins with efficiency, but goes beyond to embrace all stages of production, material and power sourcing, product design, and equipment lifecycles.
SEE SIDEBAR STORY: Two Avenues to Machine Efficiency and Sustainability
Consequently, not only are there many routes to efficiency and sustainability, there are many applications for which new tools and methods gained along the way can be tried and adjusted to best meet individual needs. The only snag is that efficiency and sustainability require some extra investment up front. Even though green projects usually pay for themselves pretty quickly, it can be very difficult to convince many builders and end users to try them. So advocates must quantify the financial gains that efficiency and sustainability can deliver, and convince their accountants and managers to invest. Still, the fact that doubters are many and innovators are few is nothing new either — so why wait to get started?
Users Demand Air, Power Savings
"In the past, we had to push for it, but attitudes have been changing, and now many customers ask for greater energy efficiency," says Terry Zarnowski, sales and marketing director at Schneider Packaging Equipment in Brewerton, N.Y. "The retail giants require energy-saving initiatives, such as Wal-Mart's Sustainability Scorecard, and so our end users look at their production lines and machines. They're realizing that being green can also mean saving green, and that efficiency and sustainability can be a big part of their overall value equation. Luckily, there are still a lot of ways to save energy."
To increase the efficiency of typical machines such as its case packers, Schneider performs an energy audit of the equipment and how it's operated, and then makes recommendations and presents options to users. For example, Schneider has long worked with SMC to evaluate and improve pneumatic performance, and recently collaborated with SMC to upgrade its standard case packers and cartoners, such as its RVCL-HS robotic vertical carton loader (Figure 1).
"We analyzed the machine's design, and SMC suggested ways to reduce compressed air usage and power consumed by right-sizing cylinders and air lines, adding a simple leak-detection system and shutting off valves when upstream product isn't coming," Zarnowski explains. "Implementing these changes added about $7,500 to the cost of the machine, but they save about $5,700 per year in the cost of producing air, and so the payback was only about 16 months. Our customer bought multiple machines, and is enjoying the ongoing savings."
Sustainability has become an umbrella term for efficient machine design and operations, as well as energy efficiency, reports Christopher Zei, global industry group vice president for the OEM business at Rockwell Automation. "Machine builders always have an eye on efficiency by minimizing downtime, reducing waste and material costs, using more accurate motion control, and using less pneumatics to save," he says. "Lately, they're using more intelligent variable-frequency drives (VFDs) and servo drives, and adding feedback devices that can serve out data for analysis."