Plate heaters - Import export

Square cartridge heaters are used where much power has to be installed near the surface of a tool, e.g. in cutting knives, sealing stations or hot plates. With a soft, malleable condition in stainless steel or nickel sheath square cartridge heaters can easily be pressed into common milled rectangular grooves. Apart from the advantageous heat transfer over ¾ of the sheath, it is not necessary to cement or cast in the heater which is imperative for round cartridge heaters. Unlike tubular heaters which are also available in square sections (see chapter Flexible Heating Pipes), the square cartridge heaters have the termination on one side and can be loaded with 16W/cm² (2.5W/in²) due to their special inside construction.

Polyester heaters also referred to as Polyester film heaters or Polyester foil heaters consist of an electrically conductive ink between two insulating respectively carrier layers of polyester. With a maximum size of 600 x 1000 mm, their average height is only 0.2 mm. As the picture examples show, practically any shape and type of cut-out is possible. Polyester foil heaters are resistant to permanent temperatures of up to 90°C (max. 100°C for short periods). It is generally not possible to predict which temperature a Polyester heating element will reach in the application, as there are extremely many influencing factors. These include not only the power, but also the mass and type of goods to be heated, the ambient temperature, air currents, the type of mounting and, of course, the control technology. Typical applications for Polyester heaters are e.g. cup warmers in coffee machines, mirror heaters, plate heat exchangers, flat applications with a target temperature below 90°C.

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.

CSN® copper and nickel are temperatureresistant connecting cables for internal wiring of electric household appliances such as hotplates, glass ceramic plates, grill appliances or storage heaters. In industrial applications CSN® Cables are preferably used for the wiring of heating elements, heating cartridges, tubular heaters, panel heaters, and quartz radiators. We manufacture these singlecore cables in cross sections up to 6 mm². Owing to their high temperature resistance up to 250 °C in the case of glass silk insulation and 600 °C in the case of mineral fibre insulation, these connecting cables meet the most demanding requirements.

Advantages of Heating Plates with Square Cartridge Heaters: -> Simple plate manufacture due to rectangular groove geometry, no deep-hole boring -> Simple heater installation by bending and pressing along the plate surface -> Complex plate geometries with bores and openings -> Optimal heat transfer due to 75% surface contact -> No casting with heat conductive compound -> Uniform temperature profiles due to thermally optimized groove layouts/power distribution and utilization of insulation plates -> high process temperatures (up to 450°C in aluminium, up to 700°C in stainless steel) Example "Heated Stamp": D=100 mm out of tempered tool steel up to max. 700°C continuous temperature. Fitted with 2 Square Cartridge Heaters 1500 W/ 230 V, 4,5 x 4,5 mm x 600 mm, with 50 mm unheated at the termination end. Annealed and formable with a nickel sheath, resistant up to 850°C surface temperature. Connection by fibreglass insulated pure nickel high-temperature leads (max. 500°C)

Micanite is a kind of insulation paper which is impregnated with a heat resistant binder and afterwards pressed in several shifts under heat and high pressure to plates. This material is heat resistant up to 350 °C, as special construction (Phlogopit) up to 450 °C, and is used for the wire wound formers as well as for the encapsulating cover plates of mica surface heaters. Because of the typical "sandwich"-construction of Micanite Flat Heating Elements and their high watt density it is necessary to use a platen to press the mica heater onto the surface to be heated. Established on the market for round Flat Heating Elements are some standard dimensions (Ø 58 / Ø 65 / Ø 80 / Ø 100 / Ø 160 / Ø 260 mm). But normally Micanite Surface Heating Elements are constructed on customer's request. Mica heaters can be metal sheathed for higher mechanical stability. This makes the heater flexible, so that it is also possible to build a band heater.