Novel THOR Technology for Orientation of Vertical XT to Completions

On conventional vertical trees (VXTs) with a tubing hanger (TH) in the wellhead (WH), orientation of the VXT to the TH system is a complicated and expensive process. Leveraging patented technology, the tree to hanger orientation ring (THOR) and tooling were implemented to save CAPEX and OPEX while eliminating risks associated with conventional orientation solutions. An open-water tool installs an external alignment feature onto the wellhead, which is oriented with the tubing hanger already installed in the wellhead. The VXT then orients onto the wellhead with the help of this external alignment feature, resulting in correct orientation with the tubing hanger. This paper discusses the novel technology and its successful development and installation for a subsea project, which revolutionizes the VXT portfolio. Rapid development of THOR technology was required along with expedient project execution. Utilizing digital-twin design techniques such as finite element analysis and operator simulations, the operating life of THOR tooling was investigated in parallel with project engineering. The novel nature of the THOR required unconventional testing, which was performed in-house. Project execution plan was implemented for engineering and manufacturing to successfully build the production equipment on schedule. Comprehensive system integration testing was completed upon the first attempt. The system was deployed to staging facilities before being delivered offshore to the customer and installed subsea in stages during April 2020. Involvement of the operators and installation contractors during the development stage made THOR's first deployment attempt a major success with zero recorded nonproductive time, even during COVID-19. THOR technology reduces the number of components as well as the weight and size of the equipment. The novel THOR equipment can be run by a light intervention vessel rather than conventional equipment, which requires mobile offshore drilling units. The time spent to deploy the VXT system is also reduced, minimizing indirect supply-chain and field-service-related carbon emissions. This further enables reduced carbon emissions and overall carbon footprint of the entire project. The field-proven THOR technology is an evolutionary orientation technology that simplifies the installation operations for the vertical tree and tubing hanger. This technology maintains the robust conventional system configuration post installation and hence does not affect reliability of the VXT system.