针对南海某气田铺管船正常铺设钢悬链线立管(Steel Catenary Riser,SCR)的作业,基于OrcaFlex数值模拟对立管进行总体动态分析,确定立管可安全作业的阈值环境条件.研究波浪方向、海流速度、立管外径、壁厚等对立管正常铺设作业窗口的影响,进一步分析不同外径、壁厚立管在不同水深下的适用性,确定立管极限安装水深.研究表明,立管作业窗口对浪向较敏感,在随浪条件下进行铺管作业更安全.随着立管外径、壁厚、表面流速增大,波高-周期作业窗口减小,极限铺设水深减小.
The normal laying of Steel Catenary Riser(SCR)with a pipe-laying vessel in a gas field of the South China Sea is simulated with OrcaFlex so that the threshold environmental conditions for the safe operation of the riser are determined.The influence of wave direction,surface velocity,outer diameter and wall thickness of the riser on the operation window is investigated.Further,the applicability of the riser with different outer diameters and wall thicknesses under different water depths is analyzed to determine the limit laying water depth of the riser with S-lay.The results show that the installation window of the riser is sensitive to the wave direction,and it is safer to lay pipe under the following wave condition.With the increase of the surface velocity and the outer diameter and wall thickness of the riser,the height-period operation window decreases and the limit laying water depth decreases.