聚乙烯复合带热缠绕弯管防腐层粘接性能评价

Evaluation on adhesion performance of polyethylene composite tape heat wound on anticorrosion coating of bends

针对3PE直管道配套聚乙烯复合带热缠绕弯管防腐层的粘接问题,系统研究了弯管不同位置粘接性能的差异,并分析了测试温度及热水浸泡老化对防腐层粘接性能衰减的影响规律。结果表明,不同区域弯管防腐层的粘接性能存在较大差异。随着测试温度的增加,防腐层与管体的剥离强度逐渐降低,热缠绕复合带的层间剥离强度均略低于胶层对FBE底层的剥离强度。随着在50℃热水中浸泡周期的增加,防腐层与管体的粘接性能呈现了初始阶段(0~60天)平稳但略有波动、后期(60~120天)快速降低的规律。针对聚乙烯复合带热缠绕工艺在搭接过渡区防腐层表面高低起伏、防腐层中间区域气泡夹杂及焊缝区的空鼓问题提出了改进建议,研究结果对管道防腐层安全服役具有参考意义。

For the adhesion of polyethylene composite tape heat wound on the anticorrosion coating of bends for 3PE straight pipe, the difference of adhesion performance in different positions of bends was systematically studied, and the influence laws of test temperature and hot water immersion aging on adhesion performance degradation of the anticorrosion coating were analyzed. The results show that the adhesion performance of bend coating in different areas varies greatly. With the increase of test temperature, the peel strength between the anticorrosion coating and pipe body decreases gradually, and the peel strength between the layers of heat wound composite tape is slightly lower than that of FBE underlying. Besides,with the increasing of immersion period in hot water at 50 ℃, the adhesion performance between the anticorrosion coating and the pipe is stable with slight fluctuations in the initial stage(0-60 d), and then decreases rapidly(60-120 d). Moreover,suggestions were put forward to improve the undulating anticorrosion surface in the lap zone, the air bubbles trapped in the middle of the anticorrosion coating and the hollowing in the weld zone, etc. Generally, the research results are of great reference significance for the safe service of anticorrosion coating of pipelines.