柔性立管环空测试技术在国内的首次应用

First Application of the Flexible Riser Annulus Test in China

目的:柔性立管是海洋油气的生命线,开展其环空测试可以为评估其状态和疲劳寿命提供基础,为确保其整体安全和完整提供保障。方法:联合具有柔性立管检测经验的挪威Kongsberg公司,对南海某浮式生产储油卸油装置(FPSO)的3根柔性立管进行环空测试。结果:3根柔性立管的保压压力(单位为大气压)分别为3.01、2.93、2.94,环空压力分别为1.25、2.86、2.95,3根柔性立管环空测试最终得到了稳定的压力;3根柔性立管的环空体积理论值(单位为升)均为1545,本次测量值分别为38、1589、417;2根柔性立管的环空排气系统流量(单位为升每小时)均大于1500。结论:本研究是柔性立管环空测试技术在国内的首次应用,本次测试的3根柔性立管的外包覆层都是完整的;3根柔性立管环空层剩余体积各不相同;3根柔性立管接头上的排气孔和整个环空排气系统应该都是通畅的;柔性立管的状态和疲劳寿命评估等将在后续论文中探讨。

Objective： Flexible risers are the lifeline of offshore oil and gas, and conducting their annulus tests can provide a basis for assessing their state and fatigue life, and provide guarantees to ensure their overall safety and integrity. Methods： 3 flexible risers of a floating production, storage, and offloading unit（FPSO） in the South China Sea were performed annulus tests by cooperating with the Norwegian Kongsberg company, which has experience in the detection of flexible risers. Results： The pressure holding pressures of the 3 flexible risers were 3.01 barg, 2.93 barg, and 2.94 barg, respectively. The annulus pressures were 1.25 barg, 2.86 barg, and 2.95 barg, respectively. And 3 flexible riser annulus tests eventually yielded stable pressure. The theoretical volume of the annular volume of 3 flexible risers were all 1545 ltrs, the current measured values of them were 38 ltrs, 1589 ltrs, and 417 ltrs, respectively. And the flow rate of the annular exhaust system of 2 flexible risers were all greater than 1500 ltrs per hour. Conclusion： The study is the first application of the flexible riser annulus test in China. The outer claddings of 3 flexible risers tested in this study were all intact. The remaining volumes of 3 flexible risers annulus layers were not the same. The vents on the flexible riser joint and the entire annulus exhaust system should be unobstructed. While the state of the flexible riser and the fatigue life assessment will be discussed in other papers.