焊接参数和环境温度对聚乙烯(PE)燃气管电熔焊温度场的影响  

Influence of Welding Parameters and Environment Temperature on the Thermal Field of Electric Fusion Welding for PE Pipes

作　　者：刘剑 郑建豹 张海 张文洲 易际研 缪海波 蔡智会 LIU Jian;ZHENG Jianbao;ZHANG Hai;ZHANG Wenzhou;YI Jiyan;MIAO Haibo;CAI Zhihui(Wenzhou Special Equipment Inspection&Science Research Institute,Wenzhou 325800,China)

机构地区：[1]温州市特种设备检测科学研究院,浙江温州325800

出　　处：《电焊机》2025年第1期87-94,共8页Electric Welding Machine

基　　金：浙江省市场监督管理局科技计划(ZC2021B066)。

摘　　要：电熔焊是连接聚乙烯(PE)燃气管的常用方法。采用SYSWELD软件建立PE100圆管电熔焊的1/4轴对称有限元模型,考虑了电热丝产生的电阻热作为体积热源,并通过空气对流和散热面散热的方式模拟焊接过程中的热交换。通过DSC+TG联用测试PE100材料的熔化温度和分解温度,获得特征温度数据。试验测得PE100材料的熔化起始温度和峰值温度分别为118℃和138℃,分解起始温度为272℃,5%质量损失标定的分解温度为350℃。熔化区宽度的预测值与测量值吻合较好,误差在5%以内,验证了所采用的计算方法的有效性和准确性。模拟结果表明,焊接电压对熔化区宽度有显著影响,较大的焊接电压产生足够的热输入,进而扩大了熔化区宽度。但过高的热输入会导致塑料的过热分解,形成孔洞,降低有效连接面积,可能会影响到接头的力学性能。环境温度通过改变焊接结构的初始温度和对流散热强度,显著影响熔化区的形成过程和最终宽度。实际生产时,有必要依据具体的环境因素对电熔套筒的预设参数进行优化和调整,以保证电熔焊的质量。Electrofusion welding is a common method for connecting polyethylene(PE)gas pipes.Using SYSWELD software,a 1/4 axisymmetric finite element model of PE100 circular pipe electrofusion welding was established,considering the resistive heat generated by the heating wire as a volumetric heat source and simulating the heat exchange during the welding process through air convection and cooling surface dissipation.The melting temperature and decomposition temperature of PE100 material were obtained through DSC+TG combined test to obtain characteristic temperature data.The experimentally measured melting onset and peak temperatures of PE100 material were 118℃ and 138℃,respectively,while the decomposition onset temperature was 272℃,and the decomposition temperature calibrated at 5% mass loss was 350℃.The predicted value of the melting zone width was in good agreement with the measured value,with an error of less than 5%,verifying the effectiveness and accuracy of the adopted calculation method.The simulation results show that the welding voltage has a significant effect on the width of the melting zone,and a larger welding voltage generates sufficient heat input,thus expanding the width of the melting zone.However,excessive heat input will lead to overheating and decomposition of the plastic,forming pores,reducing the effective connection area,and may affect the mechanical properties of the joint.The ambient temperature significantly affects the formation process and final width of the melting zone by changing the initial temperature and convection heat dissipation intensity of the welding structure.In actual production,it is necessary to optimize and adjust the preset parameters of the electrofusion sleeve according to specific environmental factors to ensure the quality of electrofusion welding.

关 键 词：PE100 电熔焊 数值仿真 温度场 焊接参数 

分 类 号：TG457.6[金属学及工艺—焊接]