Rotary hearth oven preheats, cures powder coatings

The Grieve Corp. has developed No. 816, a 500-degrees-F, gas-fired, rotary hearth oven, for preheating and curing powder coatings onto electric motor parts. Workspace dimensions are 54 by 54 by 72 in. It features 350,000 BTU/hr. installed in a modulating gas burner, while a 4,200-CFM, 3-HP recirculating blower provides horizontal airflow to the work load.

The rotary hearth oven features an aluminized steel interior and exterior with 4-in. insulated walls. Two 48-in.-dia. hearths, constructed from rolled angles and covered with perforated metal, carry the loads in process. Each hearth is designed to rotate for 15 sec., every time the motor-operated vertical lift door is opened and closed. The hearths are driven by a 1/3-HP motor through a gear reducer with torque-limiting device.