Cornfields, Inc., Gurnee, IL, contract-packs a wide variety of snack products, including candy-coated popcorn, fried and baked snack pellets, chocolate confectionery and extruded snacks, in bag sizes ranging from 1/2 to 20 oz. for high-profile multinational snack and candy companies. Product is packaged on three vertical form/fill/seal machines, each equipped with a multihead scale mounted overhead. The scale weighs the product, which drops into the vf/f/s machine and is filled into plastic bags.

Cornfields installed metal detectors after the vf/f/s machines to check the bags for metal contamination, but when these units failed to meet the strict tolerances demanded by its customers, Cornfields found that only Lock Inspection Systems could satisfy their requirement for a wide-diameter detector with tight parameters. The sensitive Compact MET 30+ Waferthin detector from Lock is capable of detecting minuscule slivers of stainless steel, enabling Cornfields to meet both its own quality control standards and those of its customers.

Cornfields has two vf/f/s machines from Hayssen Packaging Technologies and one vf/f/s machine from Matrix Packaging Machinery. A multihead scale from Yamato Corp. mounted above each vf/f/s machine weighs the product.

The Waferthin metal detector, which has a 7-in.-dia aperture, measures only 5 in. high top-to-bottom, so it fits easily between the

discharge chute from the scale and the bagging machine. These dimensions were a vital consideration for Cornfields, as they did not want to incur the extra cost and inconvenience of replacing their existing stainless-steel funnels. The Compact Waferthin is designed specifically for this type of installation in the high-speed integrated packaging systems that are increasingly popular in the snack and candy industries.

The electronics for the metal detector are mounted directly on the detector's search head and are accessible both from a keypad mounted on the search head and from a separate remote keypad. This saves valuable space in the scale and bagging machine and eliminates the need for a mounted enclosure, so the controls are easily accessible for operators if they need to determine or adjust the detector settings.

"We've found that too often metal detection equipment satisfies sensitivity claims but falls short of space or build requirements," explains Henry Cretors, president of Cornfields. "Lock's Waferthin detector met our performance specifications without causing upheaval to our production line. Without the Lock metal detectors, we would have had to halt production of some of our products and would almost certainly have lost valuable customers."

More information is available:

Metal detectors: Lock Inspection Systems, Inc., 978/343-3717.www.lockinspection.com. Circle No. 215.

Vertical form/fill/seal machines: Hayssen Packaging Technologies, 864/486-4000.www.Hayssen.com. Circle No. 216.

Vertical form/fill/seal machine: Matrix Packaging Machinery, 262/268-8300.www.matrixpm.com. Circle No. 217.

Scales: Yamato Corp., 262/236-0000.www.yamatocorp.com. Circle No. 218.