Rotary Hearth Ovens
Rotary Hearth Ovens
Rotary Heath Ovens are designed to allow loading and unloading of a single part at the same location. They are ideal for heating smaller parts at a work station where a heated part is required repetitively. As an operator removes a hot part, a cold part is loaded for heating. Our extensive experience working closely with our customers ensures we can design a rotary hearth oven for your process.
Standard Features for Rotary Hearth Ovens
- UL Listed Control Panel
- Meets the Requirements of the Following Standards:
- NFPA 86 (Standard for Ovens and Furnaces)
- NFPA 70 (National Electric Code)
- FM (Factory Mutual)
- Ovens processing combustible materials are required to have a fire suppression system per NFPA 86
- If flammable solvents or vapors are present in an oven, OSHA requires conformance with NFPA 86 Class A Oven requirements. A powered forced exhauster and other non-standard safety equipment must be added. See Class A Equipment for Solvent Processing resource page for more information.
- Adjustable manual reset excess temperature interlock to turn off heat on malfunction of main temperature controller
- Recirculating blower air flow safety switch to turn off heat on loss of recirculated air flow
- Electrical interlock shuts off heat if power to recirculating blower is interrupted
- Electric Heat Includes
- Separate heating element control contactors to turn off heat on malfunction of main control contactors
- Gas heat includes:
- Modulating burner for 1000 BTU per cubic foot natural gas at 6” water column pressure – propane available.
- Automatic pre-ignition purge period to clear accumulated gas or fumes
- Push button electric ignition
- Microprocessor based electronic flame safeguard protection to continuously monitor flame and close gas valves if flame is not present
- Powered forced exhauster to provide combustion venting
- Exhauster air flow safety switch to close gas valves on loss of venting
- Two pilot valves to guarantee gas flow to pilot can be stopped
- High and Low gas pressure switches to confirm safe operating pressure range
- Two main burner safety shut off valves with valve seat position indicator to assure gas flow to main burner can be stopped
- Proof of closure switch on one main valve to prevent igniting pilot unless main valve is closed
- Leak test station at each pilot and main burner valve to allow testing for leakage through valve
- Digital temperature controller
- Motor control push buttons and on-off heat switch
- LED pilot lights
- 5 kA short circuit current rating (SCCR)
Available construction features:
Oven design can include:
- loading platforms outside oven
- storage area for parts to be heated
- vertical or horizontal recirculated air flow
- unheated vestibules to reduce heat loss from loading opening
- continuous or indexing drive
- index triggered by other machinery
- vertical lift doors tied to indexing
- light curtains for operator safety
Hearth design can include:
- solid or perforated surface
- reinforced for heavy loads
- fixtures on hearth to position parts
- dividers on hearth to isolate individual parts
- multi-level hearth
- Operating temperatures to 800°F
- Solid or perforated hearth
- Aluminized steel or stainless steel interior
- Recirculating air flow patterns – Vertical or Horizontal air flow
- Single or multiple levels
- Indexing or continuous operation
- Electric or Gas heat
- 208 volt, 230 volt or 460 volt, 3-phase, 60 HZ – other input power available
- All welded construction
- Heavy duty, welded structural steel hearth frame welded to vertical central shaft supported by high temperature thrust bearing at bottom and expansion bearing external to oven at the top
- Heavy duty reducer, torque limiting device and variable frequency conveyor drive
- Durable, electrically isolated, Incoloy tubular heating elements
- Heat source located in heat chamber to prevent radiant heating
- High pressure recirculating blower
- Full coverage supply and return duct work with adjustable opposed louvers
- Adjustable fresh air intake and exhaust outlet damper
- Insulated with 10 lbs per cubic foot density rockwool insulation
- Aluminized steel exterior with Trilite Green enamel finish
- Brushed stainless steel control panel face
- Heavy duty access doors with explosion venting latches
- Adjustable dampers at load/unload opening positioned near load to reduce heat loss
- Slip flashing at doorways allow inner oven to expand without affecting door sealing
- Fiberglass door gasket with stainless steel spring insert
- Fully assembled and factory tested for temperature uniformity
- 1 year limited warranty
Modifications & Accessories for Rotary Hearth Ovens
Oven modification adding a programmable Temperature Controller. Microprocessor based, digital indicating, thermocouple actuated, in lieu of standard controller.
-Program Parameters: 40 profiles of up to 50 steps each, a real-time clock with battery backup to allow starting profile at any time of day
-Digital Display, 4.3” color touch screen
-Accuracy, ±0.1% of span plus 1 degree display error
-Connectivity, Relay output for alarm or other notification, two (2) USB ports, Ethernet compatible
-Up to four (4) control channels of temperature, relative humidity or vacuum
-Monitor up to16 sensors
-Math and logic functions
-Digital inputs and outputs
Modification adding a Digital Timing Temperature Controller. Microprocessor based, incorporates 99 hour 59 minute timer, starts timing temperature reaches set point and shuts down oven at end of set time.
- Digital Display, two LED, alphanumeric, 4 digit displays; 0.875″ high for temperature display and 0.500″ high for set point display
- Accuracy, ±0.1% of span plus 1 degree display error
Accessory adding a Recording Thermometer. Thermocouple actuated.
- Record: 10″ diameter circular chart 24 hour chart rotation
- Digital Display: 0.56″ high, LED, alphanumeric, 4 digit display; LED status display
- Accuracy: ±0.25%of span plus 1 degree display error
Electrical modification adding an SCR Power Controller. Features:
•Silicon controlled rectifier power controllers are completely solid state industrial controllers that ensure precise proportioning of electric power to the heating elements.
•Oven temperature is maintained smoothly and evenly over the entire temperature range of the unit.
•SCR power controllers minimize maintenance, as there are no moving parts or electrical contacts to wear out.
•Heating element fatigue is reduced since the elements do not cool between releases of electric power.
•Zero voltage firing, including the first one half cycle of voltage, minimizes radio frequency and electromagnetic interference.
•Transient voltage suppressor networks are included, and the units are provided with protective fusing.