Mica band heaters utilize different types of top grade mica. The thickness of each mica layer is carefully selected to balance between the insulating characteristics of Mica and the ease of heat transfer from the resistance ribbon to the machine barrel.
The resistance ribbon used in a Mica band heater is not restricted to the capabilities of Nichrome wire. Different alloys are considered for different applications. The internal winding is carefully designed to ensure uniform heat distribution throughout the heater.
To maximize the surface-to-surface contact, Mica band heaters are carefully rounded and formed to optimize the grip on a machine barrel. The external metallic protective sheath of a Mica band heater is made of a special alloy, which expands less than the barrel when heated. This difference in thermal expansion makes the heater grip the barrel firmly once it is energized, and this improves heat transfer. Poor heat transfer acts like a throttle and makes the resistance element inside the heater function at elevated temperatures, which eventually leads to the premature failure of the heater.
Mica band heaters are made in different construction styles, clamping mechanisms, and terminal types. Holes, cutouts, slots, thermocouple or mounting brackets can be accommodated in the design.