As economic realities force the metal forming industry to innovate, economize and streamline stamping operations, the question of which is the superior method of feeding material through the stamping operation — coil versus sheet — takes on new urgency. Coe Press Equipment, a leading manufacturer of coil-handling and material feeding equipment, recently did a head-to-head comparison of coil feeding and sheet feeding to see what efficiencies could be brought to bear on the overall stamping operation. What it found was that the choices made at the material feed level impacted not only the press operations, but the overall plant floor environment as well.

      Coe used a transfer press operation as the basis for the test. Technical and operational comparisons were based on processing similar parts using both methods. The part was a sheet metal stamping requiring flat stock material that is 36" wide x 24" long x .050" thick. The feeding operations required a progression of material to be presented to the first stamping operation on the coil feeding side, and a loose blank to be presented to the first stamping operation on the sheet feeding side. In this scenario, a 72" O.D. coil was used, containing a specific lineal footage of material. Sheet feeding was based on an optimum number of pallets of flat blanks that would contain an equal number of pieces as the coil.

      For the purposes of the comparison, an annual volume of 300,000 pieces was used. Coil material would require approximately 100 coils to be purchased from the supplier. Blank material would require...

...Continued in the pages of Twin Plant News, Subscribe Today!