Difference Between Cartridge Heater and Coil Heater

Cartridge and coil heaters are two of the most popular industrial heating systems. This blog explains a comparison of cartridge heaters and coil heaters, taking into account design, application compatibility, maintenance, and cost.  

Cartridge Heater

A cartridge heater is a cylindrical tubular heating device that delivers efficient heating for various materials, machinery, and equipment. This heater is placed into a hole in the item to be heated and provides internal radiant heat. They are utilized in a variety of manufacturing processes to provide accurate, localized heat.

Cartridge heaters are designed for easy installation and provide consistent heat distribution, with watt densities adjusted for different purposes. They are designed with a diameter that is slightly smaller than the intended hole, ensuring a tight and secure fit.

Coil Heater

Coil heaters are an advanced thermal engineering idea also known as high-performance tube heaters or cable heaters. Coil heaters provide a high heating profile and great performance in small spaces, reaching temperatures of up to 750°C. Coil heaters come in a variety of cross sections and sizes, and may be shaped into practically any geometrical design. 

Coil heaters can be tightly coiled to deliver concentrated heat or extended to meet dispersed wattage requirements. Coil heaters can also have an integrated thermocouple for accurate temperature control and rapid response. The thermocouple can be of type ‘J’ or ‘K’ and terminated anywhere inside the coil portion.

Cartridge Heater Vs Coil Heater

Construction

Cartridge heaters are usually small in design, with diameters ranging from 3mm to 25mm and lengths changing according to application needs. They are available in various sheath materials, including stainless steel and Incoloy. 

Coil heaters come in a variety of sizes and designs. They are often made with a stainless steel sheath to withstand high temperatures and resist corrosion.

 Heating Element

Cartridge heaters use a single, straight heating element that passes through the center of the cartridge. The heating element is built of various materials, including nickel-chromium and iron-chromium-aluminum alloys.  

Coil heaters, as the name implies, include a coiled heating element. The coil structure allows for consistent heat distribution across a wider surface area. Similar to cartridge heaters, coil heaters use Nichrome or FeCrAl alloys as heating sources.

Application Use

Cartridge heaters are widely used in several sectors, including plastics, packaging, semiconductors, aerospace, medical equipment, and food processing. Their applications include hot runner systems, mold heating, sealing equipment, and analytical instruments.

Coil heaters are widely used in sectors like plastics, rubber, packaging, and food processing. They are appropriate for applications requiring consistent heating, such as hot stamping, heat sealing, extrusion, and injection molding.

Maintenance

Cartridge heaters have low maintenance needs. A regular check of the heater and its connections, and the removal of any accumulated debris or impurities, is enough. 

Coil heaters require comparable maintenance, such as visual examination and cleaning. However, due to their coiled nature, you need to check for any evidence of coil deformation or corrosion that may impair their function. If a coil heater is broken, it may need to be replaced completely. 

Conclusion

The application determines whether a coil or a cartridge heater is used. Cartridge heaters are ideal for high-temperature applications and targeted heating, whereas coil heaters offer consistent heat dispersion.

Whatever you pick, Patel Heaters and Control can design and build high-quality industrial heaters for your application.