High-Temperature Gas Class A Truck Oven for Shelf-Loaded Industrial Coating Cure

The project required a high-temperature truck-loaded batch oven for industrial coating operations where coated parts, fixtures, and mixed part geometries must be processed in a controlled thermal environment. The customer’s business involves engineered coating application across a broad range of part sizes and coating types, so the oven had to support flexible loading and repeatable batch processing rather than a single dedicated product geometry.

APPLICATION REQUIREMENT

• The project required a batch oven for high-temperature industrial coating cure processing.
• The oven had to support coated components and fixtures processed in a specialty coating environment handling variable product sizes and batch contents.
• The process required a thermal platform appropriate for solvent-bearing coating systems operating within a documented Class A basis.

WORK CHAMBER / LOADING REQUIREMENT

• Required work chamber: 36 in W × 36 in D × 60 in H.
• The load format had to use a guided shelf truck for batch loading and unloading.
• The truck package had to include three 150 lb shelves with a total truck capacity of 1500 lb.
• The oven had to support repeatable airflow passage around loaded shelves and parts, making product positioning and fixturing discipline important to final processing performance.

OPERATOR / ACCESS REQUIREMENT

• The oven had to allow front loading and unloading through a single swing door.
• The floor system had to include integrated guide tracks to keep the cart aligned during loading and processing.
• The design had to support practical access to the work chamber while maintaining a compact equipment footprint.

QUALITY / PROCESS CONTROL REQUIREMENT

• The customer required repeatable high-temperature thermal processing within the stated work-zone uniformity.
• The process required programmable temperature control for defined heat-up, soak, and cooldown behavior.
• The thermal package had to provide a consistent airflow pattern across the cart-loaded work zone.

SAFETY / ENVIRONMENTAL REQUIREMENT

• The oven had to be configured as a Class A oven.
• The documented maximum volatile load basis was 0.25 gal/batch o-xylene.
• The process required powered exhaust, purge, airflow proving, flame supervision, and burner interlocks appropriate for solvent-bearing industrial coating work.

SITE / UTILITY REQUIREMENT

• Required electrical service: 480V / 3PH / 60Hz.
• Required fuel: natural gas.
• Required gas inlet pressure: 2 PSI.

The project required a controlled high-temperature forced-convection process for thermal curing of coated parts under a Class A operating basis.

TEMPERATURE REQUIREMENT

• Operating temperature basis: 750°F to 800°F.
• Maximum temperature basis: 800°F.
• Required work-zone uniformity: ±10°F.

AIRFLOW / HEAT-TRANSFER REQUIREMENT

• Airflow direction basis: full horizontal airflow.
• The process required forced-convection heat transfer across the cart-loaded work chamber.
• Using the documented recirculation airflow and the chamber cross-sectional area in the airflow direction, the first-pass chamber air velocity is approximately 107 FPM.

HEAT-INPUT REQUIREMENT

• Heat source: natural gas.
• Burner basis: Selas PC0-B.
• Burner heat input basis: 300,000 BTU/hr.
• Gas flow basis: 300 CFH.
• The burner package required controlled heat delivery suitable for sustained high-temperature batch operation.

VENTILATION / SAFETY-PROCESS REQUIREMENT

• The process required Class A exhaust and purge sequencing.
• Powered exhaust basis: 550 CFM at 1 in. W.c.
• Maximum volatile load basis: 0.25 gal/batch o-xylene.
• The operating sequence required exhaust fan start, recirculation fan start, purge, burner light-off, and controlled heat-up.

CONTROL / COOLDOWN REQUIREMENT

• Primary control basis: ramp/soak temperature control.
• The oven required a controlled shutdown profile supporting automatic cooldown and fan shutdown logic.
• The source package states that fans are not to be shut down while oven temperature is above 250°F.

To satisfy those requirements, Precision Quincy configured the project as a high-temperature gas Class A truck oven with guided truck loading, horizontal airflow, and interlocked combustion and control architecture.

OVERALL CONCEPT

• One 73-800 gas Class A truck oven.
• Compact batch configuration built around a truck-loaded work chamber.
• High-temperature thermal package developed for repeatable industrial coating cure processing.

HEATING ARCHITECTURE

• Heat source: natural gas.
• Burner: Selas PC0-B.
• Burner input: 300,000 BTU/hr.
• Gas train arranged for NFPA 86-compliant safety shutoff, pressure supervision, and modulating heat control.
• Combustion package includes double blocking valves with proof of closure, high and low gas pressure switches, and flame safety supervision.

AIRFLOW ARCHITECTURE

• Airflow pattern: full horizontal airflow.
• Recirculation system based on a 13.5 in × 5 in forward-curved fan wheel delivering 1,600 CFM at 2 in. W.c.
• The airflow circuit drives heated air across the truck load from one side of the work zone to the other for controlled cross-chamber convection.

EXHAUST / VENTILATION ARCHITECTURE

• Class A exhaust based on a PQ1 exhauster delivering 550 CFM at 1 in. W.c.
• Fresh-air damper integrated into the oven body.
• Exhaust airflow proving and purge logic are interlocked with burner enable.

CHAMBER / SHELL ARCHITECTURE

• Internal work chamber: 36 in W × 36 in D × 60 in H.
• 6-inch insulated wall construction.
• Standard wall insulation: 6 lb density mineral wool.
• Heat chamber wall construction: 1 in 8 lb Superwool plus 5 in 6 lb mineral wool.
• Interior: unpainted aluminized steel.
• Exterior finish: PQ Blue.
• The oven includes a guided insulated floor track system for truck positioning.

DOOR / LOADING ARCHITECTURE

• Single front swing door.
• One guided shelf truck sized for the work chamber.
• Truck construction includes a mild steel frame with aluminized steel shelves.

CONTROLS ARCHITECTURE

• Watlow F4T ramp/soak controller for primary temperature control.
• Dual Gefran 650L controllers for excess-temperature protection at the combustion chamber and work area.
• NEMA 12 control enclosure with UL508A open industrial control panel basis.
• Separate operator controls for exhaust fan, recirculation fan, and burner enable.
• Panel indication includes purging, burner on, and flame safety fault status.
• The control system includes fan shutdown and burner disable relay logic.

SAFETY ARCHITECTURE

• Applicable standards basis: NFPA 79, NFPA 86, UL508A.
• Safety logic includes:
• Exhaust airflow proving
• Recirculation airflow proving
• Combustion blower airflow proving
• High and low gas pressure supervision
• Purge before burner light-off
• Flame supervision and manual flame-safety reset
• Dual excess-temperature protection