Heatcraft Inc.

Robert T Stewart

Paul L Mitchell

A sheet of fin stock is lubricated by a roller coater having first and second lubricant-applying rollers adapted to engage respective opposed first and second sides of the sheet and to apply a first synthetic lubricant to both sides of the sheet as the sheet is pulled through the roller coater. The lubricated sheet is then formed into a plurality of coil fins by a conventional fin press. The first synthetic lubricant is devoid of petroleum ingredients and is water soluble. The first synthetic lubricant forms a hydrophilic coating on the fins. The fins are assembled with a plurality of hairpin tubes to form the coil. A second synthetic lubricant is introduced into each of the tubes prior to bending. The amount of the first synthetic lubricant applied to the fin sheet and the amount of second synthetic lubricant introduced into each hairpin tube are carefully controlled so that neither the first nor the second synthetic lubricant need be removed during the coil manufacturing process, thereby eliminating the need for a dedicated cleaning/degreasing operation. The first synthetic lubricant has a relatively low volatility so that a special emissions permit is not required and has relatively low BOD, FOG and COD levels so that a special water permit is not required.

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Grenada, MS, United States of America

Robert T Stewart