Thermal & Electrical Engineering
Power, voltage, resistance and heated length are matched to the required furnace duty and available power supply.
ELECTRIC HEATING ELEMENTS
Electric Radiant Tube Heater
Custom Electric Radiant Tube Heaters for Industrial Furnaces and Heat-Treatment Equipment
Xiangyuan Machinery manufactures custom electric radiant tube heaters for industrial furnaces, heat-treatment equipment, drying kilns and other thermal-processing systems.
The resistance heating assembly is installed inside a heat-resistant metal radiant tube. Heat is transferred to the outer tube and then radiated into the furnace chamber or toward the workpiece, providing stable indirect electric heating while protecting the internal heating element.
Product Overview
An Electric Radiant Tube Heater is an industrial resistance heating assembly designed for indirect radiant heating inside furnaces and thermal-processing equipment. The internal heating element is supported and electrically insulated inside a heat-resistant metal radiant tube.
During operation, electrical energy is converted into heat by the resistance element. Heat is transferred to the radiant tube surface and then radiated into the furnace chamber or toward the workpiece.
Power, voltage, tube diameter, heated length, flange arrangement and terminal direction can be engineered according to furnace temperature, atmosphere, installation space and process requirements.
Key Features
Each Electric Radiant Tube Heater is selected according to furnace temperature, atmosphere,
required heat duty, power supply, radiant-tube dimensions, mounting and terminal requirements.
Stable Radiant Heating
The long radiant-tube surface provides stable indirect heat transfer into the furnace chamber.
Cr20Ni80 Heating Element
Nickel-chromium resistance material can be used as the heating element for high-temperature furnace service.
Ceramic Insulation Support
Ceramic supports position the internal heating element and electrically isolate it from the outer metal tube.
Heat-Resistant Radiant Tube
Heat-resistant stainless steel tube materials are selected according to furnace temperature and atmosphere.
Custom Power and Voltage
Power, voltage and resistance are engineered according to the required furnace heat duty and available power supply.
Custom Tube Dimensions
Tube diameter, wall thickness, heated length and overall length can be customized according to the furnace layout.
Furnace-Wall Flange Mounting
Flanged mounting supports installation from outside the furnace and simplifies removal for maintenance.
Controlled-Atmosphere Compatibility
Configurations can be evaluated for air, nitrogen and other compatible furnace atmospheres after process review.
Drawing-Based Production
Dimensions, flange, terminal arrangement and electrical data are confirmed from approved project requirements or drawings.
Typical Technical Parameters
The following data are for reference model RT-30-220-S only. Other electrical ratings, dimensions and materials can be engineered according to project requirements.
| Parameter | Reference Specification |
|---|---|
| Reference Model | RT-30-220-S |
| Rated Power | 30 kW (+5% / -10%) |
| Rated Voltage | 220 V AC / single-phase / 50 Hz |
| Connection | Single-phase direct connection |
| Heating Element | Cr20Ni80 |
| Cold Resistance at 20 °C | 1.61 Ω ± 5% |
| Cold Current | 136.4 A |
| Hot Resistance at 750 °C | ≈ 1.77 Ω |
| Hot Current | ≈ 124 A |
| Radiant Tube Surface Temperature | 750 °C continuous; up to 850 °C short-term |
| Maximum Heating-Element Temperature | 1100 °C |
| Radiant Tube Material | 310S (0Cr25Ni20) |
| Radiant Tube Outside Diameter | Φ168 mm |
| Tube Wall Thickness | 8 mm |
| Effective Heated Length | 2200 mm |
| Overall Length | ≈ 2800 mm |
| Cold Insulation Resistance | ≥ 500 MΩ at 500 V DC |
| Hot Insulation Resistance | ≥ 1 MΩ |
| Dielectric Strength | 1500 V AC / 1 min, no breakdown |
| Reference Weight | ≈ 65 kg |
Structure, Materials, Control and Safety
Structure of the Radiant Tube Heater
A typical electric radiant tube heater includes:
- Resistance heating element
- Ceramic insulation supports
- Heat-resistant metal radiant tube
- Mounting flange
- Terminal / connection end
- Protective grounding point
The internal resistance element generates heat and is supported by ceramic insulation. Heat is transferred to the outer radiant tube and then radiated into the furnace chamber or toward the workpiece.
Materials and Customization
Material selection depends on furnace temperature, atmosphere, oxidation conditions and expected service life.
For the RT-30-220-S reference configuration:
– Heating element: Cr20Ni80
– Radiant tube: 310S heat-resistant stainless steel
– Radiant tube outside diameter: Φ168 mm
– Tube wall thickness: 8 mm
Tube diameter, wall thickness, heated length, overall length, flange dimensions, terminal arrangement and electrical rating can be customized after the furnace design and process conditions are confirmed.
Control System
Electric radiant tube heaters are resistance heating devices and should be operated through a properly rated electrical control circuit. Temperature control and power switching are configured according to the furnace system and project requirements.
Control options can include:
– Thermostat or temperature controller
– PID temperature control
– SCR / thyristor power regulation
– Contactor or staged switching
– Current monitoring
– Independent over-temperature cutoff
– PLC or furnace control cabinet integration
Safety Protection
The radiant tube metal housing must be reliably connected to protective earth. Electrical work should be carried out only after the upstream power supply has been isolated and verified de-energized.
Recommended protection can include:
– Over-current protection
– Short-circuit protection
– Independent over-temperature cutoff
– Current monitoring
– Protective grounding
– High-temperature terminal protection
– Individual branch protection for multiple heaters
– Adequate terminal-area cooling and maintenance clearance
Typical Applications
Electric Radiant Tube Heater products are used for indirect radiant heating in industrial furnaces
and thermal-processing equipment after furnace temperature, atmosphere, heat load and installation conditions are confirmed.
Heat-Treatment Furnaces
Radiant heating for annealing, tempering, aging and other controlled heat-treatment processes.
Annealing Furnaces
Providing stable radiant heat for metal annealing processes requiring controlled furnace temperature.
Tempering Furnaces
Electric radiant heating for controlled reheating and tempering of metal components.
Drying Kilns and Ovens
Radiant heating for industrial drying, curing and thermal-conditioning processes.
Controlled-Atmosphere Furnaces
Configurations can be evaluated for air, nitrogen and other compatible controlled furnace atmospheres.
Continuous Furnaces
Radiant heating for continuous production lines where stable thermal input is required along the furnace section.
Batch Furnaces
Electric radiant heating for batch-operated furnaces with cyclic heating and cooling requirements.
Industrial Ovens
Indirect electric heating for industrial ovens used in production, drying or thermal treatment.
Metal Processing Equipment
Radiant heating for metal-processing equipment requiring controlled non-contact thermal input.
Furnace Retrofit Projects
Replacement or customized radiant tube heaters for existing furnace upgrades and heating-system retrofits.
OEM Furnace Equipment
Custom radiant tube heaters for furnace manufacturers and industrial heating-equipment builders.
Special Thermal-Processing Equipment
Customized radiant heating for other compatible high-temperature industrial equipment after process review.
How to Select the Right Electric Radiant Tube Heater
Please provide the following furnace, thermal, electrical and installation data so that power,
radiant-tube material, dimensions, resistance design and protection requirements can be selected correctly.
1. Furnace Type
Provide the furnace type and main heating process.
2. Furnace Temperature
State the normal operating temperature and maximum furnace temperature.
3. Required Heating Power
Provide the required heater power or calculated furnace heat load.
4. Furnace Atmosphere
Confirm whether the furnace operates in air, nitrogen or another controlled atmosphere, and identify corrosive or combustible components where applicable.
5. Power Supply
Provide voltage, phase and frequency.
6. Radiant Tube Diameter
Provide the required outside diameter or available furnace-wall opening.
7. Effective Heated Length
State the required heated length inside the furnace.
8. Overall Length
Confirm the required overall length and available external installation space.
9. Mounting Flange
Provide flange diameter, bolt-hole arrangement and furnace-wall mounting requirements.
10. Insertion Depth
Confirm the insertion depth and position of the heated section inside the furnace.
11. Terminal Orientation
State the required terminal direction and available maintenance clearance outside the furnace.
12. Temperature Control
Confirm the temperature sensor type, control point and required temperature-control method.
13. Power Control Method
Confirm contactor switching, staged control, SCR/thyristor regulation or other project-specific requirements.
14. Safety Requirements
Confirm over-temperature protection, current monitoring, grounding and other required electrical protection.
15. Drawing, Quantity and Testing
Supply the drawing, tolerances, quantity, inspection and testing requirements.
Why Choose Xiangyuan Machinery
Xiangyuan Machinery designs and manufactures industrial electric heaters, heating elements and control systems for customized process conditions. Each Electric Radiant Tube Heater is engineered around furnace temperature, atmosphere, thermal duty, installation dimensions and electrical requirements.
Heat-Resistant Material Selection
Radiant-tube and heating-element materials are selected according to furnace temperature, atmosphere and expected operating conditions.
Flexible Mechanical Arrangement
Tube diameter, flange, insertion depth, terminal orientation and maintenance access can be customized according to the furnace layout.
Testing & Technical Support
Electrical resistance, insulation performance, dimensions and connection requirements can be checked according to the confirmed product specification before shipment.
Need a custom electric radiant tube heater?
Send us your furnace temperature, atmosphere, required power, voltage, radiant-tube dimensions, heated length, flange arrangement and installation requirements. Xiangyuan Machinery can prepare a technical proposal and quotation according to the confirmed operating conditions.