In the heating process of plastic machinery such as injection molding machines and extruders, the JB/T 4088 standard requires the insulation resistance of electric heating rings to be no less than 1 MΩ, with a cold-state withstand voltage of 1500 V. Purchasing personnel need to focus on the actual working conditions' protection requirements and temperature control accuracy, rather than merely comparing unit prices. The DJR-660 ceramic electric heating ring is suitable for AC 220 V or 380 V power supply. The power density is customized according to the size of the heated body and the heating time, and the maximum allowable working temperature can reach 450°C (depending on specific specifications).
Cast aluminum electric heating rings conduct heat evenly but are relatively heavy, while mica electric heating rings have lower cost but limited temperature resistance. Ceramic electric heating rings use ceramic strips wound with resistance wire, with an outer shell of stainless steel or galvanized sheet, offering a higher temperature resistance grade and thermal shock resistance. In scenarios requiring frequent disassembly or heating of material cylinders with high surface temperatures, the ceramic structure can reduce deformation caused by thermal expansion. For occasions with flammable and explosive gases, products with the corresponding explosion-proof rating should be selected, and it should be confirmed that the upper limit of working temperature does not exceed environmental requirements.
It is recommended to confirm the following parameters simultaneously during procurement: rated voltage and power, maximum allowable working temperature, insulation resistance, lead length and outlet method, inner diameter tolerance, and clamp form. The inner diameter tolerance of ceramic electric heating rings is usually controlled within ±0.5 mm. Clamp forms include spring clamps, bolt fastening, etc., and must match the size of the equipment's material cylinder. The lead length can be customized according to the installation position, and the outlet method can be radial or axial.
The DJR-660 ceramic electric heating ring is commonly used in plastic processing equipment such as injection molding machine material cylinders, extruder barrels, and blown film machine heating sections. It is also applied in heating parts of chemical fiber, rubber, and packaging machinery. For long material cylinders requiring zone temperature control, multiple units can be used in series or parallel, combined with temperature control instruments to achieve segmented heating.
