Coil Heaters

Coil heaters are made by placing a pair of tiny coils or two lines of straight resistance wire inside a very dense MgO medium. This core is then inserted into a stainless steel shell. These high performance heating cells can acquire temperatures of up to 1500°F.

A coil heater in its unformed straight stage can have a maximum length of 6ft and its cross-section can be square or rectangular. Thermocouple sensors could be installed internally at the tip or the middle of a heater. Power terminals, as well as ground and thermocouple wires are attached to the internal wires inside a transition adapter, which has a larger diameter than the actual heater's cross-sectional diameter.

Although coil heaters are fully annealed and can acquire any shape, they should be formed to a final shape in a single attempt. Forming and bending operations harden the outside stainless shell of a heater, and re-annealing might become necessary if changing the form is required.

The wattage in a coiled heater could be distributed, with higher wattage at the two ends, simply by stretching and distancing apart the middle loops.

Used for:
Hot runner nozzles
Cutting & sealing bars
Medical equipment
Rod, pipe & tube heating
Heat tracing
Semiconductor manufacturing