Silicone Wire Wound Heaters

Rugged. Reliable. Accurate. High-strength fiberglass reinforced silicone rubber gives the wire wound heater dimensional stability without sacrificing flexibility. Moisture and chemical resistant, HEATFLEX can be vulcanized to conform to the contours of irregularly shaped parts, equipping our wire wound heating elements with the exceptional ability to fit over your custom component and follow compound curves.

  • High watt densities
  • Excellent repeatability
  • Better choice for high flex applications
  • Flexible heaters adapt to contoured surfaces with ease
  • Freeze protection and condensation prevention
  • Resistant to many chemicals
  • Economically facilitates high resistance applications and heater sizes not lending themselves to the etching process
  • Global agency approvals: UL, CSA, TUV on most configurations.


Built to withstand adverse conditions, Heatron's robust HEATFLEX silicone wire wound heaters offer stronger, more flexible heaters along with fast, inexpensive prototyping. Our designers work with a variety of material combinations specifically chosen based on your resistance density and mechanical requirements.

Engineering services and consultation are available on every custom heating element order. Contact a specialist today for details.


HEATFLEX is one of Heatron's most popular heater designs. The flexible substrate housing and etched or wire-wound heating elements provide maximum flexibility for your design in size, configuration and technical specifications. Suitable for a wide range of industrial and commercial applications.



Custom designed to operate up to 600 volts.
Resistive element functions with AC and DC voltage sources.
Dual voltage versatility - one heater operates on two voltages.


Distributed Wattage can be used to compensate for specific areas of heat loss and create uniform substrate temperature. Operate more efficiently by applying heat where it is needed.
HEATFLEX heaters can be designed with multiple zones, controlled and operated independently. This approach saves time and minimizes design iterations in product development.


HEATFLEX can be supplied with a variety of sensors including thermocouples, thermistors and RTDs.
Our design team can assist you with custom mounting options to achieve optimal results.
Sensors can be mounted over heated and non-heated sections. Most thermocouples, thermistor or RTD sensors can be incorporated into the HEATFLEX assembly process.

Thermostats & Thermal Fuses

Designed to provide maximum efficiency for your application.
Large selection of bimetallic thermostats to perform control and safety functions. 
HEATFLEX heaters provide sensory control, including partial temperature capacity. This serves to limit the temperature of the heating element itself, is a great back-up temperature controller, and it is ideal for freeze prevention and condensation build-up in outdoor electronic enclosures.

  • Thermostats can be mounted to sense the ambient air inside the enclosure.
  • Thermostats can be mounted over a heated or non-heated section.
  • By placing the thermostat over a heated section, the thermostat will limit the temperature of the heating element itself.

Connecting Leads

19-strand silver plated copper conductor is the standard. Also, TFE, Silicone, HPN, SJO, and cordset, just to name some of the options.

Leads can be sleeved in Silicone coated fiberglass, heat shrink or stainless steel overbraid.

Attachment Methods:

Put vulcanized heaters first for superior heat transfer and long term thermal performance.

Attach and detach materials – over and over again. Snaps, Spring Clasps, Hooks, Velcro® – just about any fastener can be incorporated into the design for easy attachment to almost any part configuration.

Thermal Insulation

HEATFLEX heaters can be supplied with a variety of insulation types, typically 1/8” to 1/2” medium density Silicone rubber sponge. Heatron uses low compression set sponge for applications where heat and pressure are present.


DuPont™ Kapton®

Silicone Etch

Silicone Wire
Max Operating Temperature*
    ** 260°C     500°F
        200°C         392°F
         200°C          392°F
Min Operating Temperature
    -60°C     -73°F
    -55°C     -70°F
    -55°C     -70°F
Max Watt Density
      50 W/in2 
      60 W/in2 
      12 W/in2 
Nominal Thickness            
  0.15 mm   0.006”
 0.76 mm   0.030
  1.0 mm   0.040”
Dielectric         Strength
     3000 V/mil         
      400 V/mil           
     400 V/mil           
Max Size                            
560 x 560 mm  22" x 22"
560 x 710 mm  22" x 28
915 x 1775 mm  36" x 70"
Max Resistance
     115 Ω/in2
     115 Ω/in2  
    1000 Ω/in2  

* Higher temperatures available. ** All polyimide construction.


Dimensional Tolerance
Less than 150 mm  
Less than 6”
± 0.8 mm
± 0.03
150 to 300 mm
6” to 12”
± 1.5 mm
± 0.06”
Greater than 300 mm
Greater than 12”
± 3.0 mm
± 0.12”
Resistance Tolerances
+10% | -5%


Medical & Life Sciences

Dialysis, CPAP, DNA Analysis, Blood Diagnostics, Surgical Irrigation, Blood/Fluid Warming, Instrument Warming, MRI Equipment, Temperature Therapy, Sterilization,

Aviation & Transportation

Instrumentation, Personal Comfort Heating in Aviation, Over the Road Truck and Railcar Freeze Protection, Battery and Oil Heating, Auto and Motorcycles


Antennas, Enclosures, Microwave Repeaters, Back-Up Battery Systems

Food Service

Warming Cabinets, Heated Display Shelves, Prep Stations, Fryer Systems, Toasting/Grilling Platters


Chemical Detection, Explosives Detection, Cameras


Fuel Cells, Power Meters, Battery systems, Transmission Switches


Packaging Lines, Electronic Enclosures, Freeze Protection, Motor Heaters, Cold Storage Equipment