Kapton Flexible Heaters

Flexible heaters are regularly specified because of their light weight, thin profile, low thermal mass and flexibility. The abilities to provide an infinite array of patterns and concentrations of heat are additional characteristics. Complex shapes, contours and three-dimensional patterns are possible. Many mounting methods are available for the application of Flexible Heaters.
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Performance Capabilities

Kapton Heaters are especially thin and light weight, yet resistant to tearing and cuts. Kapton is an organic polymer that has high dielectric capabilities and tensile strength. Temperatures from -328 to 390°F (-200 to 200°C) are possible while providing a high resistance to many solvents, oils, radiation and fungus. Because of very low out-gassing properties, Kapton heaters are suitable for use in high vacuum applications. Standard bonding methods can be applied. Being transparent adds to Kapton’s versatility. Other sheath materials such as Neoprene, Mica and Mylar are available.

Applications

Resistance Element

The resistance element in Flexible Heaters is either wire wound or etched foil.

	Wire Wound Element: A fine gauge resistance wire is spiraled around a fiberglass core. The element is placed in a specifically designed pattern and vulcanized to either a silicone rubber or neoprene substrate. Advantages versus etched foil elements are: Physical strength; flexibility; smaller production quantity; conforms well to small radius bends and larger possible sizes.
	Etched Foil Element: The manufacturing process of etched foil elements is adapted from the production of printed circuit boards. A nickel resistance alloy foil is acid etched to the specific pattern, then vulcanized to the sheath material. Advantages versus wire wound are: Higher watt densities; greater area coverage of element over heater sheath; higher production quantities and complex heat distribution.

Termination

Silicone leads for temperatures to 390°F (200°C) are most often supplied, but many other types are available. The leads are attached to the element within the transition area and covered with a patch of the same material as the sheath.The entire lead transition assembly is then vulcanized to the heater sheath. Leads can be arranged to exit at about any point on the element sheath, corner, or from an external tab. Neoprene, silicone and Teflon leads along with SJ and HPN cord and plug sets can be supplied. Silicone Rubber leads are standard unless otherwise specified. Teflon leads are also available. 14, 16, 20 or 24 gauges are sized by requirement. Maximum lead length is 72″. Available with Patch and Strain Relief Tab. Patch Lead patch can be placed along the heater edge at the following positions: CW – Center of width UW – Upper corner of width LW – Lower corner of width Standard patch dimensions vary by heater size and design.  Strain Relief Tab Standard tab dimensions: 2″ long x 2-1/2″ wide. Can be placed in CW, UW or LW position. Minimum width: 2-1/2″ 2 Conductor SJ type 16/2 Cord with 2-3/4″ Round Termination Cap is often specified. Max temp is 140°F. NEMA1-15P Plug is available for 120 volt items. 3 Conductor SJ type 16/3 Cord with Round Termination Cap is also available. Ring terminal is attached to ground wire. Max temp is 140°F. NEMA1-15P Plug is available for 120 volt items.

Mounting Methods

Pressure Sensitive Adhesive (PSA) is a factory applied material for bonding Flexible Heaters to a flat, smooth surface. A peel-away protective backing allows simple field installation. The maximum element temperature for PSA use is 300°F (150°C) continuous, at no more than 5 watts per square inch. Heaters with PSA should be stored no more than 6 months before installation.Factory Vulcanizing provides excellent heat transfer from the heater element to the customer part. Strong, free of air gaps and with the longest possible heater life are advantages of Factory Vulcanizing. For field applied adhesives, an RTV Room Temperature Vulcanizing Adhesive or Contact Cement are available. Consult Ogden. Also available for Flexible Heaters are several mechanical field mounting devices such as hooks and laces, grommets and laces, spring loaded latches, snaps or velcro.

Thermostats and Sensors

Thermostats are typically integral to the heater, encapsulated in silicone rubber and mounted in a heated area. The position is determined based upon application considerations, prototyping and testing.

Thermostats separate from heater and ambient sensing thermostats in several temperature ranges are also available.

Thermocouples, RTD’s, thermistors and thermal fuses are normally mounted under a silicone rubber cap which is vulcanized to the heater sheath. The position can be anywhere on the heater surface.

All items rated 125V/15A, 250V/10A.
Thermostat can be wired separately when rating is exceeded. Typically, the differential between the on and off position is 30°F.

Tolerance: ± 5°F open ± 8°F closed Specify from the following values: Open Close Open Close 55°F 40°F 160°F 130°F (ambient sensing only) 170°F 140°F 80°F 50°F 180°F 1150°F 100°F 70°F 190°F 160°F 110°F 80°F 200°F 170°F 120°F 90°F 250°F 220°F 130°F 100°F 300°F 270°F 140°F 110°F 392°F 365°F 150°F 120°F (hi-limit only)

Adjustable Thermostat Temperature Range

Specifications

	Wire Wound	Etched Foil
Maxiumum Width	36″ (915mm)	12′ (305mm)
Maximum Length	120″ (3050mm)	30″ (760mm)
Thickness	0.555″ (1.4mm)	0.031″ (.64mm)
Resisitance Tolerance	-5 + 10%	-5 + 10%
Wattage Tolerance	-10 + 5%	-10 +5%
Minimum Ambient Temp.	-80 Deg F (-26C)	-80 Deg F (-62C)
Maximum Operation Temp.	390 Deg F (200C)	390 Deg F (200C)
Maximum Voltage	600V	600V

Thickness of Optional Silicone Sponge Insulation:
1/8″, 1/4″, or 1/2″
Thickness of Optional Foil Backing:
0.005″ (0.13mm).

The area where leads are attached adds additional thickness depending upon gauge wire used and type. Consult Ogden.

Dimension Tolerances:
Less than 6″ (150mm); ±.03″ (± .8mm);
6 – 12″ (150mm – 305mm); ±.06″ (±1.5mm);
12 – 36″ (305mm – 915mm); ±.12″ (±3.5mm);
Over 36″ (915mm); ±1%
12″ leads are standard. Gauge of wire to be determined based on amperage or other considerations.

Composite Bonding Processes and other applications may require special heat pattern or uniformity. Heat Mapping Certification is available as an option. Underwriter’s Laboratory and CSA recognition or listing apply to most configurations.

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