Silicone Rubber Heaters

Silicone rubber heaters are flexible and lightweight heaters that Silicone Rubber Heatercan operate up to 450°F. Because of their thin construction, the uniform heating pattern of its heating circuit and the closeness of this circuit to the surface of an application, the heat transfer from a silicone rubber heater is rapid and uniform. Despite being thin and flexible, silicone rubber heaters are rugged and maintain dimensional stability, due to the fiberglass grid that reinforces the silicone sheets that encapsulate the heating elements of these heaters. Silicone rubber heaters are moisture and chemical resistant and can adhere to flat or curved surfaces and can be factory vulcanized to metallic surfaces. These heaters can accommodate holes and cut-outs; they can be built with thermostats, thermocouples, RTDs or thermal fuses. Silicone rubber heaters can have different types of fasteners, and can be bonded to a surface by pressure sensitive adhesive (PSA) or room temperature vulcanizing paste (RTV).

Silicone rubber heaters have two types of heating circuits; the wire-wound style and the etched-foil style. Each style has its unique characteristics and should be selected accordingly. Wire-wound circuits are formed by creating a specific pattern out of resistance wire that is spiraled around a fiberglass core. The etched foil circuit is a flat circuit that is formed by chemically etching a resistive circuit out of nickel alloy resistance foil.

 

INDUSTRIAL APPLICATIONS

  • PHOTO PROCESSING EQUIPMENT

  • FREEZE PROTECTION

  • COMPUTERE EQUIPMENT

  • MEDICAL EQUIPMENT

  • CONDENSATION PREVENTION FOR INSTRUMENTS AND EQUIPMENT

  • CURING OF PLASTIC LAMINATES

  • SEMICONDUCTOR PROCESSING EQUIPMENT

 
 

 

RTV adhesives:

In the field, a strong bonding to application surfaces could be achieved by using room temperature adhesive pastes. Red colored RTV 106 and transparent RTV 116 are the two types of adhesives available. Both these RTV materials are adequate for temperatures up to 450°F.

RTD adhesives for silicone rubber heaters

Pressure sensitive adhesive (PSA):

Silicone rubber heaters could be made with a thin layer of high temperature (300°F) adhesive backing. This adhesive, which can easily bond to practically any surface, is supplied with a protective cover, which can be easily removed before applying the heater to any surface. Temperature and watt density restrictions should be maintained when PSA is used. Please consult factory.

Pressure sensitive adhesive for silicone rubber heaters

Mechanical fasteners:

When a silicone rubber heater is wrapped around an application, the ends of the heater can be fastened by attachments used on fabrics. Eyelets with lacing cords, Velcro hook and loop, metallic fasteners with springs, and independent straps are the most commonly used fasteners.

 

Factory vulcanization:


This is the most efficient method to bond a heater to a surface. Using high temperature and pressure, a silicone rubber heater can be vulcanized to a surface. However, bonding through this method can be carried out only in the factory.

 


Mechanical fasteners for silicone rubber heaters

 

 

Teflon or silicone lead wires

These leads are either sandwiched between the silicone layers or exit on top of the heater. A small patch is placed on the point of exit to provide extra protection. This causes the formation of a slight bump at the point where the wires are attached. To eliminate this problem, the attachment between the internal resistance wire and the lead wire could be made at an external no-heat  tab.

Silicone rubber heater teflon or silicone lead wires

SJO power cables

When silicone rubber heaters are used independently in an industrial application, they can be made with power cables that exit from a silicone transition box attached to the heater. Proper electrical plugs are available with the power cables.

Silicone rubber heater SJO power cables

Thermocouples and thermostats

Silicone rubber heaters can accommodate pre-set or adjustable thermostats, thermal cut-offs, thermal fuses, external “J” type thermocouples and RTDs. Each has a specific temperature range and maximum amperage capability; the factory should be consulted for their availability.

Silicone rubber heater thermostats and thermal fuses

 

 
 
 
 

 

Silicone Rubber Heaters Wire wound circuit Etched foil circuit
Max size 38” x 98” 24” x 30”
Thickness 0.060” 0.030”
Max temp 450°F 450°F
Max voltage 600 VAC 480 VAC
Watt density Up to 10 W/in2 * Up to 30 W/in2 *

*Depending on temperature and application.

Silicone rubber heater detail  Silicone rubber heater detail