Lewco Inc. delivered four custom conveyor ovens to a global manufacturer of electric transformers. Two of the ovens will be used for drying sand molds and the other two ovens will be used to cure parts after casting. The project also included a conveyor system that will be used to move the parts around the manufacturing cell.
According to the Sandusky, Ohio-based company, the drying ovens employ three stacked levels of gravity-roller conveyors installed on a slope to permit the sand molds to naturally flow towards the unload end. Pneumatic-powered guillotine doors on each end of the oven reportedly improve thermal efficiency and minimize heat loss.
The curing ovens were designed with three independently controlled lanes of dual-strand chain conveyor. The control system automatically selects which lane is ready to receive parts, and it will index those parts through the ovens to yield consistent dwell times at a constant temperature. At the entrance and exits outside the ovens, a custom-designed material-handling system consists of chain-driven roller conveyors, pneumatic pop-ups, pop-up chain transfers and a motorized swing-gate conveyor.