Air & cartridge heaters

Air heaters are a mechanism used to heat air and these heaters are for various types such as space heaters, radiant heaters and forced air products. Forced air products are used to control air temperature by the air circulation using a blower or fan past a heat source. The heater absorbs thermal energy as air current flows through it and then goes out of heater at an increased temperature. Radiant heaters work by the radiation of heat from a point source and heating of objects near the point source. A convection cycle (free flowing) is formed by the temperature differential which heats the surrounding air. Space heaters can work either as forced air products or as radiant heaters.

Air heaters are widely used in commercial, residential and industrial sectors such as

·        Room/space heating and HVAC systems in commercial/residential sectors

·        Melting, calcining, pre-heating, drying etc in industrial sectors

·        Air heaters are used in various applications such as plastics, textile, packaging, electronics, automotive, rubber etc.

·        Air heaters are used to dry ink, de-flash molded parts, cure adhesives and weld vinyl fabrics / plastic.

·        Air heaters are used in heat shrinking wire insulation, pre-heating processed gases, PC board / wafer drying and soldering lead frames in semiconductor industries.

There are different types of air heaters such as heat torches, radiators, room heaters, duct heaters, enclosure heaters, tubular heaters, flame heaters, forced air heaters, space heaters.

Enclosure heaters- These heaters work within enclosures and are used to control humidity and prevent freezing.

Heat torches and flame heaters- These machines work by the emission of concentrated stream or flame of unusually hot gas or air.

Tubular heaters- Tubular heating elements are bent into custom or standard shapes and these heaters are used for applications that require customization for heating.

Duct heaters- These heaters heat the air moving in the heater as these are installed in the middle of a moving gas/air.

Room heaters and space heaters- These heaters are portable and are used in confined areas as they don’t emit harmful fumes or risky pollutants.

Forced air heaters- These heaters work by the forced convection which enables movement of air past a heat source using a blower/fan.           

Radiators- These heaters consist of coils with circulated/heated media such as steam, hot water or oil.

Air heaters are powered by various energy sources such as thermal fluids, combustible solids, electricity, solar energy, combustible fluids.

Combustible fluids- These fluids are made of complex or simple hydrocarbons which can be classified into two subgroups on the basis of physical state at standard pressure and temperature such as gaseous and liquid state. At standard pressure and temperature, combustible fluids existing in gaseous state are propane and natural gas and combustible fluids existing in liquid state are gasoline, diesel, kerosene and fuel oil.

Electrically powered- These heaters use either three-phase or single-phase power and use alternating current in place of direct current. These heaters vary on the basis of watt density which is used to measure the quickness with which heat can be transferred by the industrial heater.

Cartridge heaters

These heaters are undersized for ease of installation as they heat metal parts using insertion into drilled holes. These heaters are industrial heating elements having an outer metal enclosure known as sheath and sheath is separated from resistive wiring using electrical insulation. These heaters are usually straight cylindrical tubes having diameters which enable them to pass smoothly into drilled holes with metric drill or common English sizes but heaters with high watt density require reaming holes after drilling.

There are various types of cartridge heaters such as

·        Immersion cartridge heaters

·        Insertion cartridge heaters

·        High temperature cartridge heaters

·        Split sheath cartridge heaters

Cartridge heaters find their applications in:

·        Highly corrosive applications with titanium as a sheath material

·        General applications with incoloy as a sheath material

·        Medical equipment and food service, de-ionized water with stainless steel as a sheath material

·        Patens, fluid heating, molds, semiconductor industry, metal dies, aerospace, sealing tools, hot plates with incoloy and stainless steel as a sheath material.

Here are some important features of cartridge heaters:

·        Stainless steel tubing

·        Threaded leads with silicon-impregnated mica glass insulation

·        MgO core

·        Can be customized to meet specifications

·        Superior quality nickel-chromium resistance wire

·        Special wattages, sizes and materials available upon request

Cartridge heaters have some benefits such as

·        Uniform temperatures

·        Easy and economic installation

·        Easy maintenance

·        Designed with high-grade materials

·        Corrosion and oxidation resistant

·        Maximized heat transfer