Square Cartridge Heating Element

The cartridge heater has an insulated resistive heating element encapsulated in a metal sheath. Insulation helps to maximize the heat transfer rate and insulates the heating element from the conductive sheath. Cylindrical heaters are the most common, but the cross section of the heater can also be square, rectangular, or other custom shapes.

Superbheater manufactures low, medium, and high wattage drum heaters in standard sizes and custom shapes ranging in diameter from 0.125 to 2.375 inches. The box heaters are available in either a standard heating coil inserted into a ceramic tube or a die forged box heater with a high power density. Although they look the same, their internal structures are quite different.

Standard cartridge heaters: Standard cartridge heaters have a nickel-chrome heating coil inserted into a preformed hole in a ceramic tube. Pure magnesium oxide (MgO) fillings are added to surround and support the heating elements in the holes and aid in heat transfer. These heaters also feature helically welded end covers and insulated conductors.

Cartridge heaters provide localized heat to restricted working areas that require strict thermal control. Usually, heaters are installed in molds, presses, or other machined parts that transfer heat. In other applications, the heater is immersed directly into the fluid medium. When used as an immersion heater, the heater jacket must be compatible with the fluid medium in contact with it. It is recommended to seal the end of the heater.