Silicone rubber heaters are versatile heating products used across many industrial applications. They can be made in almost any shape, with cutouts, holes and zones to match complex surfaces. That flexibility is their strength, but it also means that specifying them requires more detail than ordering a standard cylindrical cartridge heater. This guide covers what information your supplier needs to produce or source the right silicone rubber heater for your application.
What Silicone Rubber Heaters Do
A silicone rubber heater is a thin, flexible heating element sandwiched between layers of silicone rubber. The result is a heater that conforms to flat or curved surfaces and can be designed with zoned heat distribution to suit the application. Because the heater is thin and pliable, it can fit surfaces where rigid heaters cannot.
Common applications include heating drums and containers, warming composite tooling, maintaining temperature on pipes and vessels, defrosting, warming battery packs and electronics enclosures, and providing surface heat to irregularly shaped equipment.
Dimensions and Shape
The first thing your supplier needs is the shape and size of the heater. Unlike standard heaters that come in fixed diameters and lengths, silicone rubber heaters are made to fit a specific surface. Provide:
- Overall dimensions: length and width for rectangular heaters, or diameter for circular heaters
- Shape: rectangular, circular, or custom (provide a drawing for non-standard shapes)
- Cutouts and holes: if the heater needs to clear bolts, sensors, fittings or other features on the surface, mark their positions and sizes on a drawing
- Thickness: if space is constrained, specify the maximum allowable thickness.
For custom shapes, a scale drawing or a template traced from the actual surface is the most reliable way to communicate the requirement.
Watt Density and Power
Watt density for silicone rubber heaters is expressed in watts per square centimetre of heater area. The right watt density depends on the thermal mass of the object being heated, the target temperature, the heat-up time and the insulation.
Total power determines the heat input, while watt density describes how that power is distributed over the active area. These must be assessed separately. A larger active area can deliver the same total power at lower surface loading. Provide the required heat-up duty, contact surface, insulation and temperature limits so the supplier can assess both values for the complete assembly.
Specify the total wattage required along with the heater area, or state your target temperature and heat-up time so the supplier can recommend an appropriate watt density.
Voltage
State the required heater voltage and whether the supply is AC or DC. For a replacement, provide the nameplate and equipment documentation. For a new assembly, have the equipment designer confirm the circuit requirements. A voltage value does not establish phase, protection requirements or product availability.
Mounting Method
How the heater attaches to the surface affects both performance and installation. Common options:
- Pressure-sensitive adhesive (PSA): a factory-applied self-adhesive backing. Surface preparation, application procedure and temperature limits should follow the manufacturer’s instructions.
- Mechanical fastening: straps, clamps or other fixtures. Used when the heater may need to be removed for service, or on surfaces where adhesive is not practical. Fastening method and placement should be confirmed by the manufacturer.
- Vulcanised bond: the heater is bonded directly to a metal surface during manufacture. Provides excellent thermal contact. Used in OEM applications.
- Hook-and-loop (Velcro) straps: common for drum heaters and cylindrical applications where the heater wraps around the surface.
Specify your preferred mounting method, or describe the surface and installation requirements. The manufacturer can recommend the attachment approach, including any cutout design or placement requirements.
Temperature Control
Silicone rubber heaters can be supplied with or without integrated temperature control. Options include:
- No control: the heater runs at full power when energised. External control is provided by the user.
- Adjustable thermostat: a mechanical thermostat with a temperature knob, bonded to the heater surface.
- Thermocouple or RTD pocket: a sensor pocket built into the heater for connection to an external controller.
- Thermal fuse or high-limit cutout: a safety device that disconnects the heater if it exceeds a set temperature.
Specify your control requirements based on how critical the temperature accuracy is for your application.
Lead and Connector
Specify the lead exit position (which edge or corner of the heater), the required lead insulation and environmental rating, the lead length, and the connector type if a plug connection is needed rather than bare wire ends.
What to Include in Your RFQ
- Dimensions and shape (drawing preferred)
- Wattage and voltage
- Mounting method
- Maximum operating temperature
- Temperature control requirements
- Lead position, length and connector type
- Application description
- Quantity
- Any environmental requirements (outdoor use, chemical exposure, food contact)
The more detail you provide upfront, the fewer rounds of clarification are needed and the faster you receive an accurate quotation.
Related Reading
- Silicone Rubber Heaters: view product details and request a quotation
- Heaters for Aviation: composite tooling and ground support applications
- Drum Heating and Material Handling: flexible heaters for drums
- Surface and Radiant Heating: capability overview