Silicone Rubber Construction

Silicone Rubber Construction

Element Types | Lead Locations | Lead End Termination | Lead Exit Location


Flexible Heater Element Types

Wire-Wound Element Construction...................................................................................................................................
Fullchance Silicone Rubber heaters with wire-wound elements provide excellent physical strength capable of withstanding repeated flexing without compromising the life and performance of the heater. They are also very effective for manufacturing geometrically challenged shapes, including three dimensional ones.

The wire-wound element process consists of resistance wire wound on a fiberglass cord for added support and flexibility. The wire-wound element is laid out in a special designed pattern to ensure uniform heat profile and to conform to the size and shape of the silicone rubber heater, avoiding holes and cutouts, or to concentrate the heat profile in a specific section(s) of the heater as the application dictates.

Power lead wires or cord sets are attached to the heater windings with solder and firmly secured in place through a vulcanizing process, ensuring that the assembly becomes homogenous.

The wire-wound process is recommended and preferred for small to medium size quantities or to produce prototypes to prove out the design parameters prior to entering into large volume production runs, when the etched foil element designed will be more cost effective to produce.
Etched Foil Element Construction.....................................................................................................................................
  Etched Foil Silicone Rubber or Kapton® flexible heaters are made with a thin metal foil (.001"), usually a nickel base alloy, as the resistance element. The resistance pattern to be etched is designed in CAD and transferred to the foil, which is laminated to the insulating substrate. The element/substrate is then processed through an acid spray to produce the desired resistance pattern.

The top layer is then added and vulcanized for silicone rubber or laminated for Kapton® heaters. For silicone rubber heaters, lead wires are then attached to the heater and insulated with additional silicone rubber to complete the heater. For Kapton® heaters, lead wires are attached to the heater and insulated with epoxy cement to complete the heater.

The etched foil heater has exceptional heat transfer compared to wire wound elements, due to its large flat surface area. It can deliver more uniform heat profiles with higher watt densities, providing longer operating heater life. It can also be zoned with distributed wattage or separate heating circuits to compensate for load variations.

Flexible Heater Lead Location Options

Standard Leads — Teflon®
Fullchance’s standard leads are 10" long, Teflon® insulated, UL 1180, type EE, flexible, stranded, plated copper wire rated for 392°F (200°C) and 300 volts. Stripped: 1/4"
On silicone rubber heaters, the lead connections are insulated with vulcanized silicone rubber, which also acts as a strain relief.
For Kapton® insulated heaters, high temperature epoxy is used to insulate and reinforce the lead connection.

Cordset Options
HPN Cord and Plug Set
For portable heaters, a neoprene cordset can be vulcanized to the heater. The cord is 18 ga./2-wire (similar to lamp cord). Standard Length: 6 ft. (1.83 M), or custom length as specified. Can be supplied with or without a standard straight blade plug, 120Vac only.

SJO Power Cord
For industrial applications, SJO heavy duty power cords can be attached to the heaters in any desired length. Can be supplied with or without a standard straight blade plug, 120 or 240 Vac.
Optional Leads — Silicone Rubber
Ensures a moisture seal on the heater. Due to the similarity in material, the heater will fuse to the leads during the vulcanization process. Silicone rubber leads are not as abrasion resistant as Teflon® leads are.

Abrasion Protection Options
Various materials can be put over Teflon® or Silicone Rubber leads to provide mechanical or abrasion protection. The leads exit the heater as a single unit.
 
 
  • Silicone Rubber/Fiberglass Sleeving (356°F/180°C)
  • Stainless Steel Overbraid
  • Heatshrink

Special Leads Options

Special lead types and lengths in many configurations can be done by the expert designers and experienced manufacturers at Fullchance.
 

Flexible Heater Lead End Termination Options

Fullchance’s standard lead termination is stripped leads — 1/4" (6.3mm). Any type of connector can be attached to the leads to complete the assembly and make wiring into applications quick and easy.
From simple ring crimp connectors to complex male or female crimp pins and housings such as Molex® components, Fullchance does it all!
Fullchance’s expert designers and assemblers can also provide complete wire harnesses if required. Consult Fullchance with your requirements.
Crimp Connectors: insulated or non-insulated
 
 
  • Ring Terminal
  • Spade Terminal
  • 1/4" Female Straight Disconnect
  • 1/4" Female Right-Angle Disconnect
Miniature Connectors: example – Molex®
Plugs:
  • Standard 120 or 240 Vac – straight blade
  • Twist locking plugs, 120 to 480 Vac
  • Specify NEMA or manufacturer’s part number
Special Connectors and Plugs:
  • Consult Fullchance with your requirements.
 

Flexible Heater Lead Exit Location Options


A

B

C

D

E

F

G

H

J

K

L

M
  Note:
1. Oriented so X is always greater than Y;
2. Shows lead location by identification letters, A through M
3. Power leads or cord sets exiting location for shapes other than those
shown above, provide sample and/or drawing indicating location.