Thermcraft Inc. received an order for a pair of box-type chamber furnaces from a manufacturer of power-generation turbines. With a maximum temperature of 1400°F (760°C), the furnaces will be used to process turbine parts. Chamber dimensions measure 64 inches high x 84 inches wide x 60 inches deep. Each furnace is equipped with multiple heavy-duty cast plate heaters with heavy-gauge wire wound elements totaling 130 kW of power. The vertical-lift doors are opened and closed using dual synchronized pneumatic cylinders.
Temperature controls include a single-zone controller with integrated digital chart recorder/data acquisition and an independent over-temperature controller, both reading Type K thermocouples. Power is controlled by zero-cross SCR power controllers in a three-phase configuration and monitored by one ammeter per phase.