Nozzle Heaters with Housing

The Freek heat transfer nozzle heating system especially addresses manufacturers and users who operated their hotrunner nozzles with cast-in heaters in the past and would like to stick to their engineering know-how without paying the high price of this former heater design. The standard material of our Freek heat transfer nozzle heater alternative is brass, with or without coating, preferably with a slit. The slit allows the assembly of an external bendable thermocouple and facilitates the disassembly, e.g. in case of a revision and can be coiled over. This is not possible at competitor's nozzle heater solutions. Freek's tight coiling at the heater's ends provides a maximum possible power concentration (patented).

Owing to their small cross-sectional dimensions, MicroCoils are most often connected at both ends and do not permit the addition of a thermocouple. We prefer to use nickel as the sheath material here because it combines the best thermal conduction properties, high corrosion resistance and excellent deformation properties. To ensure that the standard 1000 mm PTFE-insulated connection cable can be positioned at one end, despite the standard two-ended connection of the element, in most cases the MicroCoil is formed into a hairpin shape and wound/laid in a bifilar (parallel) format. Our unformed MicroCoils are also supplied in the hairpin bend shape as standard.

HotCoils have a larger cross-sectional area and are thus capable of greater power than MicroCoils. For this reason they are used in hot runners with adequate space and where high heat densities are required. Owing to the large number of variants and for cost reasons, the sheath material for HotCoils is stainless steel - the standard for the market and thus also for Freek. HotCoils are large enough that thermocouples can be integrated into them. Our standard here is Type J (Fe-CuNi; red/blue), while Types J and K are also available conforming to the IEC and ANSI standards (see colour codes). Since the measurement point of a built-in temperature sensor is situated in the heater and never where the heat is actually required, a HotCoil with a thermocouple makes particular sense where the application allows the use of larger processing (temperature) windows or where the installation location or the design requires protection against overheating.

Characteristics of our HotMicroCoils with reflection tube are easy mounting and variable heat distribution. Because of its direct touch and toleranced fit, the sleeve coil heater allows a very good heat transmission to the nozzle. In all our HotMicroCoil heaters with reflection sleeve the assembly of a thermocouple is possible and recommended for bigger diameters and power.