Food Engineering

Metal detectors provide reliable sensitivity, zero downtime

January 1, 2011
Meat processor puts metal detectors to the test and finds one that works with a wide range of products.

Kunzler assures safety in its meat products by running them through Safeline PowerPhasePRO metal detectors, which operate on three frequencies simultaneously to detect a wide range of metals. Source: Mettler-Toledo Safeline.



Kunzler & Company, a family-owned business, manufactures more than 500 meat products including hams, franks, bacon, luncheon meats and specialty items found in retail stores, restaurants, entertainment venues and other outlets throughout the US. For more than 100 years, Kunzler has been committed to producing the finest-quality products. To meet this standard, the processor decided to purchase three new metal detectors.

“Our applications challenge metal detectors because we run a wide range of products with varying sizes, densities, moisture and salt content on each line,” explains Rodney Shultz, facilities manager at Kunzler’s Tyrone, PA manufacturing plant. “We considered metal detectors from two vendors and brought equipment from both into the plant for a side-by-side comparison. Our primary focus was detection sensitivity across our product range. We selected the PowerPhasePRO from Mettler-Toledo Safeline.”

“The first Safeline metal detector performed so well, we purchased two more for two other production lines,” adds Craig Dutrow, operations manager at the Tyrone plant.

The PowerPhasePRO metal detector operates with three simultaneous frequencies, which achieves the highest sensitivity across a broad range of products by automatically accommodating variations. The metal detector allows a family of products (product clustering) to be run with no operator intervention during changeovers without sacrificing sensitivity. High-frequency coil technology and advanced head geometry work on all types of metal contamination, from ferrous and non-ferrous tramp metal to difficult-to-detect stainless steel fragments. A Faraday screen located between the detector coil system and the product being inspected filters out interfering signals that might cause false-positive indications.

“We test the sensitivity of each metal detector at every changeover and at least once a day,” says Dutrow. “It takes only 30 seconds to change over the PowerPhasePRO metal detector. We can either pull down a preprogrammed product recipe or we can auto-learn each product.”

During its production shift, Kunzler keeps the room at 36° to 38°F. During the sanitation shift, the high-temperature, high-pressure washdown causes the temperature and humidity in the room to soar. To operate reliably, the metal detectors must handle these temperature extremes. They must also be watertight so the electronics are not compromised. Featuring an IP69K-rated control panel, the PowerPhasePRO metal detectors exceed NEMA 4X specifications.

“At Kunzler, our highest priority is assuring a wholesome, safe product for our customers,” concludes Dave Grazier, vice president and general manager. “The Safeline metal detectors have helped us achieve just that with perfectly reliable sensitivity and zero downtime.”



For more information:
Sarrina Crowley, 813-889-9500, sarrina.crowley@mt.com.