The oven walls, ceiling and roof are made of 20 gauge or thicker steel that has been aluminized or G90 galvanized. The oven utilizes a double panel design. The interior walls and roof are formed into 6” panels to receive factory-supplied insulation. Mineral wool insulation of at least 6# density is inserted between these inner panels and the external skins during installation. The main oven enclosure components are bolted together, typically on 6” centers. Threaded inserts in key parts help simplify assembly. When using roof mounted heat units or double load-in frontals, the ovens are equipped with support beams to increase rigidity. No welding is required.
Door thickness is included in the overall dimensions cited for the oven cabin. The oven doors are a composite design made of 11, 16, 18, and 20 gauge components that house mineral wool insulation of not less than 6# density. The doors feature support casters and adjustable hinge assemblies. To assure proper explosion relief and allow for emergency egress, the doors include a positive latching device that secures one door to the frontal header and floor, and allows the second door to latch to it using friction latches. Friction latches, often known as “panic latches” or “slam latches” enable the doors to be opened from the inside and also serve to safely vent excessive positive pressure from the oven enclosure. Doors feature fiberglass or siliconized rubber gasket material to minimize heat loss.
The heat unit and exhaust are controlled via a remote control panel in a NEMA enclosure. The control panel allows the operator to see a digital display of the heat unit’s output air temperature and adjust the unit accordingly. The control panel includes a variety of safety devices, including audible and visual alarms. The control system uses a variable frequency device (VFD) to adjust the atmosphere inside the oven by fine-tuning the performance of the exhaust fan.
The oven is equipped with a range of redundant safety devices:
- High and low pressure gas safety valves
- Manual gas shut-off
- Ignition sensor with auto shut-down
- Combustion safeguard
- Flame safety switch
- Powered air circulation fan
- Powered air exhaust fan
- Intake air proving switch
- Exhaust air proving switch
- High temperature safety switch
- Oven temperature sensor
- Purge timer for combustion
- Purge timer for oven operation
- Motor overload protection
- Fan/belt/motor guards
- Explosion relief design
A high-performance ventilation fan assembly is mounted on-site to the shop floor using antivibration bushings. The assembly uses a backwards-inclined fan mated to a motor drive via a belt system. The fan intake extends through a special wall skin and special wall panel. The exhaust drive components are housed in a ventilated steel enclosure. This system requires the use of 8” I.D. Double-wall (Type B) exhaust ducting with a high-flow exhaust cap that prevents the intrusion of water.
Exhaust duct, duct mounting adapters, combustion supply fan intake duct, gas piping to the gas train, gas valve ventilation piping, parts for electrical service connection to the control panel, and field wiring components are provided by other companies and are not considered part of the deliverable.