(44) The MI nozzle heater from Watlow® is a high-performance heater. Its performance and name are derived from Watlow’s exclusive mineral insulation - a material with a much higher thermal conductivity than mica and hard ceramic insulators used in conventional heaters.
A thin layer of the "high" thermal conductive MI material is used to electrically insulate the element wire from the inside diameter of the heater sheath. A thicker, "low" thermal conductivity layer backs up the element wire, directing the heat inward toward the heated part. The result is more efficient heat transfer - a performance solution lowering element wire temperatures and increasing heater life.
(12) The Watlow pre-coiled, cable nozzle heater has been formed into a compact, tightly wound coil to supply 360 degrees of heat. This heater features a 5 in. (127 mm) long, no-heat tail section, which eliminates failures in the adapter area due to overheating.
This cable nozzle heater is manufactured with Watlow’s swaged compaction process. This process provides a greater compaction of the MgO insulation than the competitor’s rolling process. Compacting MgO insulation into a solid mass results in excellent heat conductivity and high dielectric strength.