A Fortune 500 company ordered an oven capable of curing a specialized coating while maintaining relative humidity above 40 percent RH.
Lewco Inc. was able to design a custom batch oven that will operate around 135°F (51°C) and sustain temperature uniformity of ±3°F (±1.6°C) in the qualified zone. The oven includes a top-mounted heater box with heat capacity of 380,000 BTU/hr and an 8,000-cfm circulation fan. A variable-speed drive is included on an exhaust fan to facilitate faster cool-down cycles.
Maintaining relative humidity above 40 percent RH at elevated temperatures proved challenging. The amount of moisture air can hold increases as temperature increases. To combat this issue, Lewco’s engineering team utilized a humidification system to inject moisture directly into the oven’s circulated airstream. A custom PLC/PC-based control system was developed to ensure all parameters are monitored and controlled.
The circulation and exhaust fans were upgraded to Air Movement and Control Association (AMCA) “C” spark-resistant construction for safety.