Heating Element Selection Guide

A cartridge heater is a compact metal rod that slides into a drilled hole in a metal part and heats it from the inside. Nickel-chrome wire is wound on a ceramic core, packed with magnesium oxide and sealed in a stainless sheath. It carries far more power per square centimetre than any other element, which is why moulds, dies and platens use it.

A straight tubular heater is the simplest form of tubular element: one straight rod with no bends and a terminal at each end. It is made for places that already have a straight bore, pipe or channel, where the element can sit in without changing direction.

A formed tubular heater is a tubular element bent into shape after it is made: a U, a ring, a spiral, or whatever the drawing calls for. Bending lets you fit a long heated length into a small space, or match the element to the shape of the part it heats.

A finned tubular heater is a tubular element with thin metal fins wound and welded around the sheath. The fins multiply the surface touching the air by three to five times, so the same wattage transfers at a much lower sheath temperature. It is the standard choice for heating air and ducts.

A screw plug immersion heater is a hairpin element brazed or welded into a threaded plug, so it screws straight into a boss on the side or the top of a tank. It is the simplest sealed way to put heat inside a vessel, and it suits tanks up to a few kilowatts at low and medium pressure.

A flanged immersion heater is a bundle of hairpin elements welded into a flange that bolts onto a matching flange on the vessel. It is how large powers are put into a tank — tens of kilowatts, three phase — and it is the build used where there is pressure, a hot oil circuit, or a boiler.

A water heater element is the screw-in element that heats a storage water heater or a hot water cylinder. It is usually a stainless steel or brass hairpin on a threaded plug, with a pocket down the middle for the thermostat, and it is chosen mainly by how hard the water is.

A samovar heater element is the small stainless element that sits in the water chamber of an electric samovar or a tea urn. It is usually a ring or a hairpin of 1 to 3 kW in a food-grade stainless sheath, and it spends its life in water that is boiled and refilled several times a day.

An oil and chemical immersion heater is built for liquids that punish an element: thermal oil, diesel, mazut, acids, alkalis and plating solutions. It runs at a low watt density so the sheath never gets hot enough to char the oil, and its sheath material is chosen for what the liquid does to metal.

A mica band heater is the thin, fast type of band heater. Flat nickel-chrome ribbon is wound over a mica sheet, covered with more mica and closed inside a stainless steel band about three millimetres thick. It heats an injection barrel quickly and cheaply, and we supply it for working temperatures up to 300 °C.

A ceramic band heater carries its resistance wire threaded through interlocking ceramic bricks, with a ceramic fibre blanket and a stainless frame behind them. We supply it for working temperatures up to 500 °C, it keeps heating even where contact with the barrel is imperfect, and its built-in insulation means less of its heat is lost to the workshop.

A nozzle heater is a small, narrow band heater made for the tip of an injection machine or a hot runner nozzle. It wraps a diameter of only 15 to 60 mm, often carries its own thermocouple, and holds the melt at temperature through the last few centimetres before it enters the mould.

A strip heater is a long, narrow flat element, usually 25 to 60 mm wide, that bolts along a bar, an edge or a plate and heats it in a line. Fitted with fins it becomes an air heater instead, and it is the simplest way to add heat to a surface that has no room for anything thicker.

A plate heater is a wide flat element that heats an area rather than a line. A resistance circuit is spread across a rectangular plate — clamped between metal sheets or cast into aluminium — so the whole face comes up to temperature together. It is used under vessels, moulds, tables and heated surfaces.

A heat press heater is the element built into the platen of a press — a heat transfer press, a laminating press, a hot stamping or a vulcanising machine. Its whole job is an even temperature across the pressing face, because everything the press makes is only as good as the coldest corner of that face.

A silicone rubber heater is a thin sheet, one and a half to three millimetres thick, with an etched foil or wound wire circuit sealed between fibreglass reinforced silicone. It bends around curves, follows an irregular shape, and can be made in almost any outline, up to about 230 °C.

A drum and tank heater is a flexible jacket that straps around the outside of a drum, a barrel or a small tank and warms the contents through the wall. Nothing goes into the liquid, so it suits material that must not be contaminated and vessels that have no opening to fit an element into.

A quartz heater is a coiled resistance wire inside a clear quartz tube. The tube reaches 900 to 1200 °C and radiates medium-wave infrared, which most plastics, coatings and water absorb well. It reaches working output in a second or two and is the general-purpose radiant element for drying and forming.

A halogen heater is a tungsten filament in a halogen-filled quartz lamp, running at up to 2200 °C. It emits short-wave infrared, reaches full output in under a second, and goes cold almost as fast. It is chosen where heat has to be intense, local, and switched on and off with the process.

A ceramic infrared heater is a resistance coil embedded in a glazed ceramic body that radiates long-wave infrared from a face running at 300 to 750 °C. It is slow, steady and robust, and it is the radiant element used where plastic has to be heated evenly without being scorched.

A silicon carbide heater is a ceramic rod that glows in open air at furnace temperatures up to about 1600 °C. It has no sheath and no wire — the rod itself is the resistance. It ages by slowly gaining resistance, so the furnace that runs it needs a transformer with tappings from the start.

A ceramic heater for high temperature work carries its resistance wire inside a ceramic body rather than leaving it bare in the chamber. Wire threaded through ceramic tubes and beads, or set into a fibre module, reaches about 1200 °C while staying protected from the load and from what the furnace gives off.

A furnace heater in its simplest form is an open coil of resistance wire laid in grooves in the lining or hung on ceramic supports inside the chamber. Iron-chrome-aluminium wire reaches about 1400 °C, nickel-chrome about 1200, and the coil is wound and pitched for the furnace it goes into.

A molybdenum heater is a wire, strip or rod element for vacuum and inert-gas furnaces. It reaches about 1700 °C, but only where there is no oxygen — molybdenum burns away in air above roughly 400 °C. It is the element used for sintering, brazing and crystal growing under vacuum.