Custom Food Processing Equipment and Systems



NEWSLETTER

Volume 40, No. 8

Gem Equipment’s product line is built around conveyors.  Many of these conveyors convey product through a processing medium such as steam, hot water, hot oil or provide batter coating.   While much of the belting for this equipment is purchased from suppliers, blancher belts are manufactured by this company.  This belt consists of panels with heavy duty corrosion resistant side chains.  Parts for fryer and batter belts are furnished to the manufacturer of the wire mesh belting.  For fryers, Gem furnishes skid shoes and skirt blocks.  The same belt supplier manufacturer rod belts used for batter applicators, blow off and fryer feed conveyors.  These belts use side chains with machined chain links manufactured by Gem.  The links are machined from stainless steel bar stock.  While use of castings was considered, they were not price competitive. An unmachined casting was the same price as the cost of the finished machined link.

This chain is composed of 3/4 inch pitch stainless steel pintle shaped links.  The belt consists of cross rods that extend the full width of the belt on 3/8 inch centers.  Every other cross rod also serves as a pin for the side chain.  These side chains are an upgrade.  The belts, used in the early 1990’s, had stainless twelve gauge steel side links furnished by the belt manufacturer.  These were cut out of twelve gauge stainless steel sheet and formed into a U shape.  As production increased, batter equipment grew larger to handle the increased volume.  The larger equipment eventually overloaded the sheet metal side chains causing failure.  The first side chain to fail was on a unit that was only slightly larger than similar equipment already in operation.  This led to the hope that operating conditions, not overloading, were the cause of the failure.  The customer did not agree and wanted the problem eliminated.  Further evaluation proved the customer was correct.  Fortunately, this processor, with some difficulty, was able to keep operating while the problem was addressed.  It took three months to design and manufacture replacement side chains which were installed on the existing belt.  The new chain was successful. 

Part of the design process was to perform a pull test.  On these tests, the part is subjected to increasing load until it fails.  The force to fail is recorded.  With a chain, the weakest part is discovered.  With the original chain, the sheet metal link failed.  When the pintle link was tested, the pin failed. This test indicated that the redesigned link would meet operational requirements.  This chain has been used on Gem’s batter system belts for over twenty-five years.  While the chain has not changed, the belts have.  Increased capacity has led to wider batter applicator belts.  The increased width required a center chain to assure satisfactory performance.  All three chains are driven by sprockets on the head shaft. A chain in the product carrying section of the belt works because the links are small enough to keep product from passing through the trapezoid shaped opening formed by two links.  Batter systems, with belts ten foot wide, are in operation.  These belts have two intermediate drive chains.  Operating speeds normally exceed one hundred feet per minute with some as high as two hundred feet per minute.  This company has experience with wide belt design, manufacture and application.