With critical applications in residential, commercial and industrial processes, heater elements are manufactured from a variety of materials and in many configurations. Heater elements are capable of providing heat from room temperature up to over 1300°F.
Heater elements are widely used, as most appliances that require heat to perform their processes use a heater element of one kind or another. In fact, ovens, clothes dryers, water heaters, electric furnaces and other industrial, commercial and consumer appliances use heater elements extensively.
Industrial processes use heating elements in countless process heating applications in various types of industrial electric heaters. In addition, radiating types of heater elements such as immersion heater elements, quartz heater elements, and infrared heater elements are used to heat liquids or air in industrial ovens, storage tanks, pressure vessels, steam generators, boilers, water treatment facilities, and many other kinds of equipment. Some of the more common types of heater elements include tubular heater elements, ceramic heater elements, and heater coils.
Heater elements within electric heaters are mainly composed of three elements: an insulating core, a heat conductive coil wrapped around the insulation, and an encasing sheath made from stainless steel, aluminum, nickel or iron.
Insulating cores are necessary for most types of electric heaters to retain and absorb electrical energy so that it might be released as heat energy by surrounding coils or materials.
However, coiled wire heater elements, such as those used as household dryer heating elements, have no insulating core but transfer heat directly to the air through blown convection.
In higher heat applications, cores are responsible for converting electrical energy into heat energy and are heating elements’ major component. Heater element cores are generally made from either NiChrome, a high resistance 80% nickel 20% chromium compound, or from a Positive Thermal Coefficient ceramic, which is a highly heat resistant barium titanate/lead titanate composite. Ceramics and NiChrome are by far the most common insulation materials, although various heater elements may use mineral insulation such as magnesium oxide, mica or fiberglass, depending on the heater’s application requirements.