The Industry Technology Facilitator (ITF), in collaboration with Maersk Oil, Nexen, Shell, Siccar Point Energy, TechnipFMC and the Oil and Gas Technology Centre (OGTC), is leading a joint industry project (JIP) to investigate an alternative well foundation technology for subsea exploration and production wells.
The initiative, which also includes another unnamed operator, represents the first collaborative project launched between the ITF and OGTC, with the Oil and Gas Authority (OGA) actively participating in an observer capacity and contributing technical support to the project.
The aim of the JIP is to examine the versatility and robustness of Conductor Anchor Node (CAN®) technology as an alternative well foundation for most seabed soils.
Developed by Neodrill, a Norway-based company, the CAN system uses high load carrying capacity suction anchors to secure seafloor mooring points via a large diameter, relatively short cylinder.
Unlike conventional methods, no cement is required therefore negating risk of conductor problems due to cementing failure. The CAN also provides a well foundation to be drilled or jetted through, or with a pre-installed short conductor. It has already been proven in 17 installations to date with 14 runs in Norway and one on the UKCS.
The initial phase of the ‘CAN-based pre-rig well construction’ JIP will examine the results from CAN installations performed so far and will assess its suitability in non-clay seabed soils, such as sand and mixed soils. It will explore the potential to safely drill out a pre-installed shorter conductor (CAN®-ductor) to provide structural support for top-hole well construction.
As a CAN-supported conductor will behave differently to conventional conductors, basic finite element analyses will also be performed to demonstrate its load and bending capacities, as well as fatigue management. This stage of the project is expected to last between six to eight months with further phases and field trials anticipated.
Dr Patrick O’Brien, CEO of ITF said: “Traditional conductors have been used in the offshore industry for more than half a century, with well-known and documented issues around maintaining verticality and providing a solid base to support further well architecture. The aim of the JIP is to explore the effectiveness of CAN technology in different well foundations and increase its capabilities in subsea exploration and production wells.
“This JIP is the latest in several collaborative initiatives facilitated by ITF and the first project to use leveraged funding from the OGTC.”
CAN® capabilities will be field tested as part of Neodrill’s normal operations and installation projects and results fed back to JIP participants. This will include assessing the feasibility of shallow-set CAN-integrated conductors to potentially replace conventional deeper-set unsupported technology.
Future phases of the project will potentially explore the use of CAN technology to unlock small oil pools, to facilitate cheaper single production well construction and for faster and lower cost plugging and abandonment operations.
Jostein Aleksandersen, CEO of NeoDrill, added: “We see this JIP as a milestone in bringing the CAN technology to a wider user group within the UKCS. Building on the knowledge we have obtained from previous runs, we can assess its suitability for other substances including sand. Compared to the conventional conductor, we already know that CAN demonstrates many advantages including the ability to save rigs time and well costs, as a smaller and more cost-efficient vessel is used for CAN/conductor installation ahead of the drilling unit arrival.
“The JIP aims to demonstrate further cost efficiencies as well as robust and versatile solutions for subsea exploration and production wells.”
Read the article online at: https://www.oilfieldtechnology.com/exploration/18122017/well-foundation-technology-under-the-microscope-to-cut-well-costs-improve-safety-and-reduce-environmental-impact/