水封隧道内油气管道补口材料的应用效果

Application Effect of Joint Coating for Oil and Gas Pipeline in Water-Sealed Tunnel

通过6条水封隧道内油气管道补口的检测数据,总结了热熔胶型热收缩带补口、液体环氧补口、黏弹体胶带+聚合物外护带补口的应用效果,分析了水封隧道内不同补口材料的失效原因。结果表明:热收缩带补口大面积整体失粘导致密封失效,主要原因是施工质量控制不严;液体环氧补口在水封隧道内应用效果偏差,主要原因是水渗透进入涂层与基体界面处,造成液体环氧涂层鼓泡和附着力严重下降;黏弹体胶带在不同水封隧道内的应用效果差异较大,个别隧道内黏弹体胶带出现搭接、压接不实导致补口密封失效。

Based on the inspection datas of oil and gas pipeline joint coatings in 6 water-sealed tunnels, the application conditions of hot-melt adhesive heat shrinkable tape joint coating, liquid epoxy joint coating, viscoelastic tape + polymer outer protective tape joint coating were summarized. The reasons for the failure of different joint coating materials in water-sealed tunnel were analyzed. The results showed that a large area of the overall loss of adhesion of heat shrinkable tape joint coating caused sealing failure, the main reason was that the construction quality control was not strict. The application effect of liquid epoxy patch in water-sealed tunnel was relatively poor, the main reason was that water penetrated into the interface between coating and substrate, causing bubbling and severe decrease of adhesion of liquid epoxy coating. The application effect of viscoelastic tape in different water-sealed tunnels was quite different. In some tunnels, the viscoelastic tape had overlapped and improper crimping, resulting in the sealing failure of joint coating.