中国塑料 ›› 2021, Vol. 35 ›› Issue (9): 64-68.DOI: 10.19491/j.issn.1001-9278.2021.09.010

• 加工与应用 • 上一篇    下一篇

聚乙烯电熔接头工艺缺陷与力学相关性研究

王志刚(), 杨波(), 李智, 彭国平, 姜再佳, 利观宝   

  1. 广州特种承压设备检测研究院,广州 510663
  • 收稿日期:2021-03-01 出版日期:2021-09-26 发布日期:2021-09-23
  • 作者简介:王志刚(1989—),男,工程师,从事聚乙烯燃气管道检验检测等研究工作,orinwang8851@163.com
  • 基金资助:
    广州市市场监督管理局科技项目(2020kj15);国家市场监督管理总局科技项目(2019MK159)

Study on Correlation Between Process Defect and Mechanical Properties of Polyethylene Pipe Elector⁃fusion Joints

WANG Zhigang(), YANG Bo(), LI Zhi, PENG Guoping, JIANG Zaijia, LI Guanbao   

  1. Guangzhou Special Pressure Equipment Inspection and Research Institute,Guangzhou 510663,China
  • Received:2021-03-01 Online:2021-09-26 Published:2021-09-23
  • Contact: YANG Bo

摘要:

采用超声相控阵检测技术(PA)测量不同焊接时间下聚乙烯管道电熔接头热影响区边缘宽度l,并通过挤压剥离试验、傅里叶变换红外光谱(FTIR)试验和差示扫描量热(DSC)试验分别测试接头熔融区脆性剥离百分比(Cc)、官能团组成和结晶度(Xc),最终建立接头热影响区边缘线宽度l与焊接性能Hc的对应关系,实现电熔接头焊接性能的无损评价。结果表明,随着焊接时间t的增加,接头热影响区边缘呈指数增长趋势沿金属丝向外壁移动,接头焊接性能先逐渐提高后降低。当焊接时间t=50 s时,l=2.21 mm、Xc=53.03 %,此时接头焊接性能Hc达到最大值96.21 %,当t<40 s时,lXc偏低,接头出现冷焊缺陷;相反,当t>70 s时,接头熔融区金属丝出现错位现象,融合面的聚乙烯分子由于高温氧化反应而出现过焊缺陷,两者都会导致接头焊接性能下降。

关键词: 超声相控阵检测技术, 聚乙烯管道, 电熔接头, 工艺缺陷, 焊接性能

Abstract:

An ultrasonic phased array detection technology was proposed to measure the edge width (l) of Heat Affected Zone(HAZ) of polyethylene pipe elector?fusion joints under different welding time (t). The percentage of brittle peel, composition of functional groups and crystallinity (Xc) were measured by extrusion peel, FTIR and DSC, and then the relationship between (l) and welding performance (Hc) was established to realize the non?destructive testing of the elector?fusion joint. The results indicated that the HAZ was moved to the outer wall in an exponential growth trend with an increase in welding time. The welding performance of the joint was improved first and then tended to decrease. When t=50 s, l=2.21 mm, Xc=53.03 %, thewelding performance reached a maximum value of 96.21 %. When t<40 s, l and Xc were slightly lower, and there were cold welding defects on the joint. In contrast, when t>70 s, there were dislocation and fusion on the metal wire in the melting zone of the joint appears. The over?welding defects also took place on the joints due to a high?temperature oxidation reaction. Both of two defects led to a decrease in the joint welding performance.

Key words: ultrasonic phased array detection technology, polyethylene pipe, elector?fusion joint, process defect, welding performance

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