Energy-saving improvements in heating coils

With China's economic reforms, traditional industrial products are undergoing various improvements. Heating coils are gradually shifting from high-energy consumption to energy-saving options, which will align with international trends.

Heating coils, as auxiliary heating devices for injection molding machines, typically account for over 20% of the machine's total energy consumption. Since 2013, numerous technology companies have invested heavily in R&D to improve energy efficiency, resulting in the development of two broad categories of energy-saving heating coils: infrared and electromagnetic.

The following is a brief introduction to these two technologies:

Electromagnetic heating coils: Electromagnetic heating coils utilize components of an electronic circuit board to generate an alternating magnetic field. When an iron container is placed on top of the magnetic field, the container's surface cuts through the alternating magnetic field, generating alternating currents (eddy currents) in the metal at the bottom of the container. These eddy currents cause the iron atoms at the bottom of the container to move at high speeds and irregularly. The collision and friction between the atoms generate heat, which in turn heats the product. Because the heat is generated by the iron container itself, the heat conversion rate is exceptionally high, reaching up to 95%. The advanced technology ensures the energy-saving benefits of electromagnetic heating. Currently, energy-saving electromagnetic heating coil modifications are widely used in plastic injection molding machines, extruders, film blowing machines, wire drawing machines, plastic film, pipes, wire, and other machinery, as well as in food processing, textiles, printing and dyeing, metallurgy, light industry, machinery, surface heat treatment and welding, boilers, and water boilers, replacing traditional energy sources.

Infrared energy-saving heating coils utilize a new infrared heating element with an electrical-to-heat conversion efficiency exceeding 99.8%. The unidirectional infrared radiation conduction method significantly improves the heat transfer efficiency between the heating element and the barrel. The use of aerospace-grade aerosol felt adhesive offers a thermal conductivity as low as 0.013 W/m.K, ensuring the surface temperature of the heating coil does not exceed 70°C. The third-generation anti-radiation surface coating reduces the surface temperature to 50°C. This overcomes the critical drawbacks of traditional heating coils: low electrical-to-heat conversion efficiency, low thermal efficiency, and high surface temperature. This not only achieves energy savings of over 30%, but also improves the workshop working environment.