The voltage range of each country is different (100V-440V), the power range of the electric heating tube is different (100W-5000W), the use environment is different, the diameter of the electric heating tube is different, etc., which requires the design requirements and manufacturing process of the resistance wire of the product to be higher and higher. In China, although the electric heating tube has been produced for 20 years, but the electric heating tube manufacturing technology is still very backward, many products with small rated voltage but large rated power due to the limitation of the production process, so that the diameter of the single resistance wire is large so that the strength of the resistance wire is too high, resulting in the wire winding machine can not be wound, the welding place of the resistance wire ring and the lead rod during the powder loading process and shrinking process is easy to pull off, resulting in the problem that the length of the electric heating tube tube is more than 1500mm can not be manufactured; For the pipe selected for household electric heating tube (C>6. 2mm、6. 5mm、8. 0 mm、8. 5mm)、定格電圧が小さく、定格電力が大きい製品の場合、抵抗要件を満たすために、単一の抵抗線構造が使用される場合、直径抵抗線の曲げ強度を大きくする必要があり、抵抗線の曲げ強度が過剰になり、抵抗線リングの外径と電熱管の内壁との間の巻き取り距離が短すぎて、電気的性能に深刻な影響を与えます。電気加熱管の。
