海底管道可双向通球水下三通的设计与安装

Design and installation of underwater tee joint of bi-directional pig for submarine pipelines

水下三通在海底管道分布密集的区域具有广阔的应用前景。在绥中36-1油田一期调整开发工程中,首次在国内应用了可双向通球水下三通。与普通Y形三通和可转向Y形三通相比,可双向通球水下三通使主、支管道均可实现双向通球,因此其清管操作不会受到油气输送方向的限制,使海底管道的总体布置更加灵活。针对水下三通传统安装方法存在的缺陷,提出了等长管段预安装水下三通法,用铺管船预先铺设等长直管段,再由等长水下三通段进行替换,该方法提高了管道施工效率,降低了安装难度和风险,节省了工程投资,对海洋石油工程具有借鉴意义。

Experts expect that underwater tee joint has an wide application perspective in the areas where submarine pipelines are laid intensively. It is the fi rst time in China that the underwater tee joint of bi-directional pig is applied in the fi rst phase of the exploitation project of Suizhong 36-1 Offshore Oilf ield. Compared with the general Y-shaped joint and turnable Y-shaped joint, the bi-directional pigging for main pipe and branch pipe can both be realized by using the underwater tee joint,the cleaning operation will not be restricted along the direction of oil and gas transmission,and this can make the general layout of submarine pipelines greater flexibility. The pre-installation method of underwater tee joint using equal-length pipe is presented to offset the existed defects in ordinary installation methods of underwater tee joint. The equal-length straight pipes are laid in advance with pipe-laying vessel to replace them with equal-length underwater tee joints. This method can improve the eff iciency of pipeline construction,reduce the installation difficulty and risk,and save engineering investment,which can be used for reference in offshore petroleum projects.