Electric Heating Ring
An electric heating ring (also known as a heating coil or heating ring) is an annular electric heating element, with electric heating alloy wire as the core heating material, mica soft board or ceramic core as the insulating material, and an outer covering of aluminum or stainless steel plate. It converts electrical energy into heat energy to achieve enveloping heating of cylindrical objects such as barrels, molds, and pipes. It is widely used in plastic molding and industrial heat treatment equipment such as injection molding machines, extruders, film blowing machines, and hot runner systems.
Core Classification and Applicable Scenarios
Type Typical Operating Temperature Core Features Applicable Scenarios Average Lifespan (Continuous Operation)
Stainless Steel Mica Heating Ring 150–500℃ Low cost, light weight, uniform surface heating, but sensitive to moisture and vibration Old equipment renovation, small and medium-tonnage injection molding machines, cost-sensitive occasions 6,000–10,000 hours
Stainless Steel Ceramic Heating Ring 300–700℃ High temperature resistance, corrosion resistance, good insulation, fast heating High-temperature extrusion, PVC/halogen-containing plastic processing, food and pharmaceutical grade equipment 10,000–15,000 hours
Cast Aluminum Heating Ring ≤350℃ Integral die-casting, uniform heat conduction, high mechanical strength, good shock resistance Medium and low temperature injection molding, working conditions requiring rapid heating, multi-zone temperature linkage 8,000–12,000 hours
Cast Copper Heating Ring ≤650℃ Extremely high thermal conductivity, extremely fast heating, power density up to 8W/cm² Precision injection molding, engineering plastic processing, scenarios with strict temperature control requirements More than 10,000 hours
Tubular Electric Heating Ring 100–400℃ Compact structure, low cost, easy replacement Packaging machinery, extrusion sections with less demanding temperature requirements 8,000–12,000 hours
Nano Infrared Heating Ring Up to 1150℃ Radiant heat transfer, energy saving rate 30%-80%,外壳可触摸 Energy-saving renovation, strict temperature control scenarios, continuous high-load working conditions More than 2 times that of ordinary heaters
Electromagnetic Induction Heating Ring — The barrel itself generates heat, thermal efficiency ≥95%, power saving 30%-70% Energy-saving upgrade of old injection molding machines, energy management platform access needs More than 10,000 hours
Core Elements of Selection
1. Temperature Matching (Most Critical)
≤350℃: Cast aluminum/mica ring (first choice for cost-effectiveness)
350℃～500℃: Ceramic ring
500℃～700℃: Cast copper ring or high-temperature ceramic ring
>700℃: Nano infrared ring
It is recommended to reserve a 50℃～100℃ safety margin to avoid long-term extreme operation accelerating aging.
2. Power and Size Matching
Power calculation: Determined according to barrel size, required temperature, and production efficiency. Too low power leads to slow heating and affects production; too high power may cause unstable temperature control or scorched plastic.
Size matching: The inner diameter of the heating ring must closely match the outer diameter of the barrel, with a gap of <0.5mm, and the contact area must reach more than 80%; excessive gap will reduce heat transfer efficiency by more than 30%.
Surface load control: Mica ring 2.5-3W/cm², ceramic ring up to 6.5W/cm², cast aluminum ring up to 3.5W/cm², cast copper ring up to 8W/cm².
3. Material and Medium Adaptation
Ordinary plastics (PE/PP/PS): Mica ring or cast aluminum ring is sufficient
Engineering plastics (PC/PA/POM): Ceramic ring or cast copper ring
Corrosive materials (PVC/halogen-containing): Ceramic ring (strong corrosion resistance)
Precision injection molding/medical consumables: Cast copper ring or cast aluminum ring with integrated thermocouple hole (±1℃ temperature control)
4. Safety and Protection
Insulation resistance: ≥50MΩ (cold state)
Protection level: Conventional IP54, IP54 or above required for humid/dusty workshops
Essential protection: Overheat protection, leakage protection, over-temperature alarm
Explosion-proof certification: Ex d/Ex e certified products must be selected for flammable and explosive environments
Mainstream Manufacturer Resources
Jiangsu (especially the area of Baoying in Yangzhou, Yancheng, and Xinghua in Taizhou) is the core industrial belt for electric heating rings in China, with highly concentrated manufacturers. When purchasing, prioritize local industrial belts, which have significant advantages in after-sales response and logistics costs.
Yangzhou Local Manufacturers
Baoying County Antai Electric Heating Appliance Factory (Baoying County, founded in 2002): An old-brand electric heating appliance factory, mainly producing electric heating rings (plates), cast aluminum heaters, stainless steel heaters, ceramic/quartz heaters, etc. Its "a new type of electric heating plate" obtained a national patent and passed ISO 9001 series certification. Customers cover the pharmaceutical, machinery, packaging, and building materials industries.
Baoying County Huaguang Electric Heating Appliance Co., Ltd.: Mica heating rings withstand voltage 1500V/1min, suitable for high-voltage working conditions, power deviation controlled within ±5%, and a sales network established in East China.
Yancheng Industrial Belt
Jiangsu Tongya Electric Heating Technology Co., Ltd.: 40 years of experience in electric heating R&D and production, 8 invention patents, 47 utility model patents, EU CE certification, high-tech enterprise recognition. It has long-term supporting cooperation with Yonggao Pipe, Haier, Bayer, BASF, Sinopec, Mitsubishi, etc. Its mica heating rings have good insulation, high temperature resistance, and high thermal efficiency.
Yancheng Hengneng Electric Heating Machinery Co., Ltd. (Yifeng Town, 18 years of experience): Cast aluminum heaters use a special alloy formula, with a service life of 5-8 years; mica heating rings use German imported mica sheets and Japanese resistance wire, with a lifespan of more than 50,000 hours and a failure rate of less than 0.5%.
Yancheng Shengman Electric Heating Machinery Co., Ltd.: Specializes in manufacturing air-cooled cast aluminum heaters, cast copper heaters, and far-infrared heaters, and can design and manufacture special specifications according to customer needs.
Jiangsu Tuomao Machinery Co., Ltd.: Stainless steel mica heating rings use multi-layer mica sheet insulation, and cast copper heating rings improve thermal conductivity by more than 20%, supporting non-standard customization.
Yancheng Taiya Electric Heating Appliance Co., Ltd. / Jiangsu Hongguang Electric Heating Appliance Co., Ltd.: Integrating research and development, production and manufacturing, online sales, and market sales, focusing on quality, integrity, and one-stop service.
Taizhou Xinghua Industrial Belt
Xinghua Weipeng Electric Heating Appliance Factory (Zhangguo Town): Mainly produces mica heating rings, single-head/double-head electric heating tubes, etc. Materials cover 304/316L stainless steel and titanium alloy, insulation resistance ≥100MΩ, temperature resistance from -20℃ to 800℃, and regular products shipped in 3 days.
Feiyue Electric Heating Appliance (Taizhou Feiyue) (Zhangguo Town, 25 years of experience): Deeply engaged in the industry for 25 years, with annual production capacity of more than 5 million pieces, ISO9001 certification, using laser welding and integrated corrugated forming processes, temperature resistance over 800℃, and lifespan over 10,000 hours.
Yilingba Electric Heater (Taizhou Yilingba) (Dainan Town): Mainly produces 304/316/310S stainless steel electric heating tubes and explosion-proof heating tubes. Finned electric heating tubes expand the heat dissipation area by 2-3 times, supporting customization of voltage 12-440V and power 50W-20KW.
Other Manufacturers in Jiangsu
Dongtai Rexin Electric Heating Appliance Co., Ltd. (Dongtai Shiyan Town): Serves more than a thousand customers, prices 15%-25% lower than traders, supports minimum order of 50 pieces, delivers small batch orders in 24-48 hours, and provides one-stop supply of "electric heating elements + temperature control instruments + installation accessories".
Jiangsu Fengcheng Electric Heating Appliance Co., Ltd.: Focuses on lightweight design of heating ring structures, reducing weight by about 22% at the same power. The standard series supports IP54 protection level, suitable for cost reduction and efficiency improvement needs in production line automation upgrades.
Wuxi Keruite Electric Heating Technology Co., Ltd.: Independently developed PID temperature control system, temperature fluctuation controlled within ±0.5℃, using halogen-free mica sheets and environmentally friendly insulation materials, and passed RoHS and REACH certification.
National Famous Brands
Nengzhiyuan Energy Saving Technology Co., Ltd.: Pioneer of nano infrared electric heating rings, energy saving rate 30%-80%, investment payback period 6-9 months, and promises to bear all renovation costs if the energy saving rate is less than 30%.
Guangzhou Zhenglong Industrial Co., Ltd.: Specializes in producing industrial electric heating components, products covering electroplating, chemical, plastic, machinery, electronics (PCB) and other industries, providing special products such as Teflon heaters and titanium heaters.
Executive Standards
JB/T 2379-2016: Metal tubular electric heating elements (core standard)
GB 3836 series: Electrical equipment for explosive atmospheres (basis for explosion-proof certification)
IEC 60335-2-12:2024: Safety requirements for electric heating plates/rings (new version released by the International Electrotechnical Commission in August 2024)
ISO 9001: Quality management system certification (standard for mainstream manufacturers)
Installation and Usage Precautions
No dry burning: It is forbidden to turn on the heating ring for a long time without plastic raw material to prevent internal overheating and burnout.
Installation specifications: Before installation, remove old material, oil stains, and rust from the contact surface between the barrel and the heating ring; tighten the fixing screws evenly diagonally to ensure full contact; the gap should be <0.5mm.
Insulation matching: It is recommended to install an external insulation cover (insulation cotton thickness ≥15mm) to reduce heat loss, which can lower the ambient temperature by 3℃-8℃.
Voltage matching: 220V or 380V is commonly used in China, and some imported equipment uses 110V. The equipment nameplate must be confirmed.
Regular inspection: Use a multimeter to measure cold resistance (P=U²/R). If the resistance changes by more than ±15%, it needs to be replaced; if the insulation resistance is lower than 50MΩ, it needs to be replaced.
Shutdown cooling: After shutdown, maintain a cooling delay of >5 minutes to prevent thermal stress from causing ceramic insulators to crack.
