Electric Heated Cabinet Ovens for Aerospace Component Testing

The equipment was developed for an aerospace application requiring a group of matching cabinet ovens for repeatable elevated-temperature batch testing. The summary below focuses on the delivered equipment architecture and performance basis.

APPLICATION REQUIREMENT

• The equipment was used for testing aerospace components in a controlled elevated-temperature batch environment.
• A repeatable batch-process platform was required rather than a one-off laboratory fixture.
• Five identical ovens were required to support a multi-unit processing environment with consistent test conditions across all units.

WORK CHAMBER / LOAD REQUIREMENT

• Required work chamber: 48 in W × 30 in D × 48 in H.
• Shelving required across the order, including 250 lb and 100 lb 316 stainless-steel shelves.
• Maximum shelved capacity per oven: 750 lb. Shelf spacing adjustable at 3 in increments.

PROCESS REQUIREMENT

• The system had to support controlled elevated-temperature testing with repeatable airflow and temperature conditions across all five identical units.

SAFETY REQUIREMENT

• The ovens were configured as NFPA 86 Class A units. Maximum VOC load basis: 0.17 gal/batch.
• The process required powered exhaust, purge sequencing, and airflow proving as part of the safe operating sequence.

UTILITY / SITE REQUIREMENT

• Required electrical service: 480V / 3PH / 60Hz. Full load amperage: approximately 45.7–46.6 A per oven.

MATERIAL / CONSTRUCTION REQUIREMENT

• Interior walls and recirculation airstream components were required to be 316 stainless steel with seam-welded interior wall construction.
• Floor: 3/16 in 316 stainless-steel plate. Exhauster: 304 stainless steel.

These thermal process requirements were established from the need for controlled thermal testing of aerospace components in a compact cabinet batch oven platform.

TEMPERATURE CAPABILITY

• Operating temperature: 350°F.
• Maximum temperature: 550°F.
• Required work-area uniformity: ±10°F.

PROCESS BASIS

• The thermal process basis is batch testing of aerospace components at controlled elevated temperature.
• The process required repeatable temperature exposure in matching ovens across the five-unit order, with consistent conditions at each unit.

HEAT INPUT REQUIREMENT

• Heat source: electric resistance heat.
• Heater bank: 21 elements × 1,500 W. Total installed heat: 31.5 kW.
• Heat control basis: solid-state relay control.

AIRFLOW DELIVERY REQUIREMENTS

• Airflow style: full horizontal airflow.
• Recirculation airflow basis: 1,500 CFM at 2 in. w.c. Recirculation fan motor: 1.5 HP.

EXHAUST / VENTILATION BASIS

• Exhaust fan: PQ1 exhauster. Exhaust airflow: 225 CFM at 1 in. w.c. Exhaust fan motor: 0.75 HP.
• Airflow switches used on both exhaust and recirculation fans as part of the safe operating sequence.
• Oven classification basis: NFPA 86 Class A. Purge timer basis: 3 minutes minimum.

THERMAL INSTRUMENTATION / CONTROL BASIS

• Primary controller: WATLOW F4T ramp/soak temperature controller with data acquisition.
• Work-area thermocouple type: Type J.
• Work-area excess-temperature protection: Gefran 650L high-limit arrangement.

To deliver the customer and thermal process requirements for this aerospace testing application, the following equipment concept and architecture was developed.

OVERALL CONCEPT

• Five identical electric-heated 40B-550 cabinet ovens configured for aerospace component testing.
• Designed as Class A full-horizontal-airflow ovens in a standardized cabinet platform suited for multi-unit deployment with consistent performance across all units.

HEATING ARCHITECTURE

• Heat source: electric resistance. Total heat: 31.5 kW from 21 × 1,500 W elements.
• Heat control basis: solid-state relay control.

AIRFLOW / RECIRCULATION ARCHITECTURE

• Airflow pattern: full horizontal airflow.
• Recirculation fan: 1,500 CFM at 2 in. w.c.; 1.5 HP motor.
• Exhaust fan: PQ1 exhauster — 225 CFM at 1 in. w.c.; 0.75 HP motor.

CHAMBER / CONSTRUCTION ARCHITECTURE

• Internal work chamber: 48 in W × 30 in D × 48 in H.
• Wall thickness: 4 in. Insulation: 4 in of 6 lb mineral wool.
• Interior material: 316 stainless steel with seam-welded interior walls.
• Floor: 3/16 in 316 stainless-steel plate. Recirculation airstream components: 316 stainless steel. Exhauster: 304 stainless steel.
• Door style: two swing doors. Shelf spacing: 3 in adjustable increments. Maximum shelved capacity: 750 lb per oven.

CONTROLS ARCHITECTURE

• Oven-mounted NEMA 1 control enclosure, 42 in × 30 in × 12 in, listed to UL 508A Open Industrial Control Panel.
• WATLOW F4T ramp/soak controller with data acquisition. USB access port on enclosure face.
• Gefran 650L work-area excess-temperature controller. Type J thermocouples.
• Applicable standards basis: NFPA 79, NFPA 86, UL 508A.

SAFETY / COMPLIANCE ARCHITECTURE

• NFPA 86 Class A architecture including purge timer (3-minute minimum), airflow switches on exhaust and recirculation fans, excess-temperature protection, and powered Class A exhaust.

SHIPPING / INSTALLATION ARCHITECTURE

• Built as a standardized cabinet platform for multi-unit order fulfillment.
• First unit lead time was shorter than the remaining units within the five-oven batch.