Conveyorized Electric Motor Stator Curing Oven for EV Motor Manufacturing

The process requirement was to cure electric-motor stators within an automated EV-motor manufacturing cell. Each stator weighed approximately 66 lb, and the system had to handle a total batch mass of approximately 4,752 lb. The oven had to function as one element within a robotic load/unload sequence, with all product handling automated rather than manual.

APPLICATION REQUIREMENT

• The equipment had to cure stators used in electric-vehicle motor production as part of an automated
  manufacturing cell.
• The process was designed around automated tray-based handling with robotic load and unload, requiring the oven to function as one integrated module within the broader cell architecture.
• Production rate basis: approximately 111 parts per hour.

ROBOTIC INTERFACE REQUIREMENT

• Repeatable robotic interaction at the load and unload position was a key requirement. Product trays had to present in a precisely known location outside the oven chamber so the robotic system could reliably place and remove parts.
• The conveyor position had to be mechanically repeatable, and the tray-holding arrangement had to center and secure the tray during robotic engagement.
• A pneumatic positioning system was required to push the customer tray into the correct location for robotic pickup and placement, creating a mechanically repeatable handoff point between the oven conveyor and the surrounding automated cell.

PROCESS CONCEPT REQUIREMENT

• The intended process concept was not to raise cold parts from ambient to cure temperature. Parts were expected to enter the oven already preheated, making the oven function as a heated holding and curing chamber within the broader production cell.
• The oven therefore had to maintain process temperature and controlled residence time across all internal stations rather than deliver aggressive heat-up from ambient.

SAFETY / CLASSIFICATION REQUIREMENT

• The oven was required to be designed as an NFPA 86 Class A unit to accommodate the VOC-bearing process conditions associated with the curing material system.
• VOC loading basis: approximately 164 grams per hour.

UTILITY REQUIREMENT

• Required electrical service: 480V / 3PH / 60Hz. Full load amperage: approximately 188 A.
• Required pneumatic supply: 60 PSI minimum.

The thermal process requirements were established from the need to cure electric-vehicle motor stators in a controlled indexed-conveyor holding chamber within an automated manufacturing cell.

TEMPERATURE CAPABILITY

• Operating temperature: 356°F. Maximum operating temperature: 450°F.
• Empty-chamber uniformity: ±15°F setpoint.

PROCESS BASIS

• The thermal process basis is curing and controlled thermal holding of preheated EV motor stators within an automated manufacturing cell.
• Because parts arrived preheated, the oven's thermal role was to maintain parts within the required curing environment across the full residence time rather than drive a cold-part heat-up from ambient.

HEAT INPUT REQUIREMENT

• Heat source: electric resistance heat. Total installed heat: 126 kW across four heater banks.
• Heater bank distribution: Banks 1 and 2 at 27 kW each; Banks 3 and 4 at 36 kW each.

AIRFLOW DELIVERY REQUIREMENTS

• Airflow pattern: vertical bottom-up. Heated air driven upward through the product zone and tray structure.
• Total circulated air volume: approximately 10,241 SCFM.
• Recirculation fan: New York Blower 278 PLR plug fan — 10,250 CFM at 3.5 in. w.c.; 10 HP motor.
• Supply and return concept: pressurized supply plenum with adjustable air ports and matched return plenum system.

EXHAUST / VENTILATION BASIS

• Exhaust fan: PQ1 exhauster — approximately 155 CFM at 1 in. w.c.; 0.75 HP motor. Exhaust opening: 3.5 in. × 7.5 in.
• Oven classification: NFPA 86 Class A. VOC loading basis: approximately 164 grams per hour.

To deliver the process requirements for this EV motor stator curing application, the following equipment concept and architecture was developed.

OVERALL CONCEPT

• One conveyorized indexed electric Class A oven with 13 internal product stations and a 20 in. product index, integrated into an automated EV-motor manufacturing cell with robotic load and unload.
• The design emphasized repeatable motion control, controlled bottom-up airflow, and automation-ready tray positioning rather than manual batch loading.

HEATING ARCHITECTURE

• Heat source: electric resistance heat. Total installed heat: 126 kW across four heater banks (27 kW / 27 kW / 36 kW / 36 kW).
• Heat control: solid-state relay control per bank. Process controller: Watlow F4T. Overtemperature protection: Gefran controller.

AIRFLOW / RECIRCULATION ARCHITECTURE

• Airflow pattern: vertical bottom-up.
• Recirculation fan: New York Blower 278 PLR plug fan — 10,250 CFM at 3.5 in. w.c.; 10 HP motor; Allen-Bradley PowerFlex 525 VFD.
• Exhaust: PQ1 exhauster — approximately 155 CFM at 1 in. w.c.; 0.75 HP motor.

CONVEYOR / HANDLING ARCHITECTURE

• Conveyor type: Conveyor type: double-pitch, oversized-roller, carbon-steel chain with positive-engagement sprockets and automatic pneumatic tensioning. Custom-built roller chain guides.
• Drive: Allen-Bradley VPL motor with Kinetix 5500 servo drive. Conveyor speed during index: 13 ft/min. Total index time: approximately 14.94 seconds. Belt return path inside the heated chamber.
• Load/unload position: 12 o'clock position of the drive sprocket, outside the oven chamber.
• Tray-centering concept: clamps/locking mechanisms with adjustable hard stops and pneumatic positioning for robotic pickup and placement.

SHELL / CONSTRUCTION ARCHITECTURE

• Work chamber dimensions: approximately 142 in. L × 76 in. W × 46 in. H.
• Overall exterior dimensions: (oven body only): approximately 172 in. L × 88 in. W × 78 in. H. Overall system dimensions: approximately 250 in. L × 106 in. W × 110 in. H.
• Main wall construction: 6 in. thick with 6 in. of 6 lb mineral wool. Front wall: 4 in. thick with 4 in. of 6 lb mineral wool.
• Interior: aluminized steel. Exterior: carbon steel, Precision Quincy Blue finish. Approximate shipping weight: 25,000 lb.

DOOR / ACCESS ARCHITECTURE

• Entrance and exit doors: pneumatically actuated vertical guillotine doors.
• Two side access doors on the oven body with Allen-Bradley SensaGuard interlocks.
• Conveyor opening width: 68 in. each end. Conveyor height: 47.5 in. above finished floor.

CONTROLS ARCHITECTURE

• PLC: Allen-Bradley CompactLogix 5069-L330ER. HMI: Allen-Bradley PanelView Plus 7 Standard, 10 in.
• Temperature controller: Watlow F4T. Overtemperature control: Gefran. Fan drives: Allen-Bradley PowerFlex 525 VFDs.
• Conveyor servo drive: Allen-Bradley Kinetix 5500 with VPL motor.
• Controls architecture: remote-mounted NEMA 12 high-voltage and low-voltage control enclosures with separate oven junction box and external network-device mounting panel.
• Safety: Allen-Bradley SensaGuard interlocks on side access doors; exhaust and recirculation airflow switches; ATC purge timer; local E-stop affecting conveyor operation.
• Applicable standards basis: NFPA 79, NFPA 86, UL 508A.