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An Alternative to Diverging Roller Size Graders

Nutra Manufacturing increased throughput on its nutritional supplement packaging line with the use of an Impulse size grader.

Symetix Impulse Size GraderNutra Manufacturing is the manufacturing arm of GNC, the largest global specialty retailer of nutritional supplements. With GNC’s “quality first” principle guiding every step, Nutra uses the latest technologies to produce the highest quality supplements. To consistently maintain their ultra-high quality standards while increasing throughput and easing operations, Nutra recently replaced three of its diverging roller size graders with Impulse™/P size graders from SYMETIX on its packaging line.

“For commercial manufacturers of softgels, there are only two technologies to size grade that I am aware of – traditional diverging roller size graders and now Impulse size graders,” noted Don Deegan, Senior Director, Softgel Operations at Nutra. 

Jeff Tweedy, Director of Production at Nutra added, “Impulse gets us to our quality end-point faster, safer and easier. Compared to diverging roller size graders, Impulse has few moving parts and is virtually maintenance free. And the new technology is objective in its measure.”

Designed to size grade solid-dose nutraceuticals and pharmaceuticals, Impulse/P features a sanitary stainless steel bed and removable decks with holes that are perfectly sized for each product. Available with two or three grading decks to achieve two- or three-way size separation, Nutra selected three-deck systems, which remove twins, clusters, empties, and under- and over-diameter softgels.

“Impulse is designed for quick changeover. The system can be cleared, cleaned and changed over in less than 15 minutes without tools,” noted Jim Asbill, Softgel Engineering and Maintenance Manager at Nutra. Deegan added, ”By comparison, the diverging roller size graders take an hour or more to change over, and they need to be adjusted by the operator, which introduces a lot of subjectivity. With Impulse, the decks have fixed hole sizes, which create a repeatable operation. The benefit is the consistency of product going to customers.”

To determine the system’s effectiveness in removing out-of-tolerance softgels, Nutra performed a comparative study soon after they purchased their first Impulse in 2008. “We found that the SYMETIX unit was unquestionably superior in the removal of capsules that did not meet a fixed size range,” noted Asbill. “The variability that exists from row to row with the roller sorter simply does not come into play with the SYMETIX unit.”

Currently, Nutra has three Impulse size graders and plans to install more. “The up-front cost of Impulse is higher, but we don’t spend money on parts and labor, and there is virtually no unexpected downtime,” said Asbill. “The maintenance problems with the diverging roller size graders make the Impulse graders very attractive.”

Impulse features few moving parts and no rotating parts to wear. An oil-free electromagnetic drive offers low maintenance and extreme durability. “With Impulse, there is minimal need for routine maintenance. Unlike the diverging roller size graders, which are full of moving parts – rollers, bearings, sprockets and chains – that are maintenance-intensive,” said Asbill. “Even when we do the routine maintenance on these old systems, we still have considerable reactive maintenance, and that translates into money on parts and labor and unscheduled downtime because when a size grader goes down, we stop the line.”

“On top of all the operational and maintenance advantages of Impulse, it is capable of handling 10 times the throughput in roughly half the floorspace of a diverging roller size grader,” noted Tweedy. With a footprint of only 27 inches wide and 68 inches long, Impulse handles up to 1,000,000 softgels or tablets per hour, which is more than Nutra needs. “It’s also safer and quieter, which improves our work environment. With zero pinch points, Impulse reduces the risk of employee injury, and it’s amazingly quiet. Anything that contributes to noise reduction in the plant is beneficial.”

At Nutra, the three Impulse size graders are integrated with upstream and downstream equipment to create continuous production lines. A large infeed hopper and an electronically controlled gate make Impulse easy to integrate. For manufacturers with batch processes, the Impulse can be batch fed.

“Before we installed our first Impulse, I was a doubter. I expected that, with the natural variation of softgel capsules, we’d lose market-acceptable yield,” noted Deegan. “But the reality is that we have maintained our yields, and we have improved the consistency of deliverable product.”

“Customer satisfaction is our number one goal,” concluded Tweedy. “The Impulse size grader is one important piece of the process that allows us to ensure customers get only the highest quality product.”

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