数字射线在燃气聚乙烯管道电熔接头泄漏分析中的应用
Application of Digital Ray in Leakage Analysis of Gas Polyethylene Pipeline Electric Fusion Joints
赵番1
作者信息
- 1. 上海市特种设备监督检验技术研究院 上海压力管道智能检测工程技术研究中心
- 折叠
摘要
埋地聚乙烯管道电熔焊接采用电阻丝加热,使电熔管件与2 根管道融合成为一个整体.早期的电熔焊接以半自动焊机为主,需要焊工根据经验手动设定焊接时间、焊接电压和冷却时间等参数,易设置不当且缺乏有效的无损检测手段,焊接质量难以保证.针对聚乙烯管道电熔接头泄漏事故,从电熔接头部位宏观检验角度出发进行分析后可知,管道加工时端面垂直度不够,管件与管道承插时同轴度不足,导致熔合区失效.通过数字射线检测可知,管件过焊使得电阻丝发生错位,聚乙烯材料黏结力不足,导致电阻丝区失效.借助于轴向切割试验和拉伸剥离试验,进一步明确了缺陷类型与电熔接头强度性能的关系.最后对管道现场施工和检验给出了建议.
Abstract
The electric fusion welding of buried polyethylene pipelines used resistance wire heating to fuse the electric fusion fittings with two pipelines into a whole.Early electric fusion welding mainly relied on semi-automatic welding machines,which required welders to manually set parameters such as welding time,welding voltage,and cooling time based on experience.Improper settings were prone to occur,and due to the lack of effective non-destructive testing methods,welding quality was difficult to guarantee.After analyzing the leakage accident of polyethylene pipeline electric fusion joint from the perspective of macroscopic inspection of the electric fusion joint,it was found that the verticality of the end face during pipeline processing was insufficient,and the coaxiality between the pipe fittings and the pipeline socket was insufficient,resulting in the failure of the fusion zone.Through digital radiographic testing,it was known that excessive welding of the pipe fittings caused misalignment of the resistance wire,resulting in insufficient bonding strength of the polyethylene material and failure of the resistance wire area.By means of axial cutting tests and tensile peeling tests,the relationship between defect types and the strength performance of electric fusion joints was further clarified.Finally,suggestions were provided for on-site construction and inspection of pipelines.
关键词
泄漏/宏观检验/数字射线/错位Key words
Leakage/Macroscopic inspection/Digital radiography/Misalignment引用本文复制引用
基金项目
上海市市场监督管理局科研项目(2023MK032)
出版年
2024
NETL
NSTL
万方数据