Petroleum and natural gas industries — Drilling and production equipment — Offshore conductor design, setting depth and installation
This document specifies the requirements and recommendations for the design, setting depth and installation of conductors for the offshore petroleum and natural gas industries. This document specifically addresses:
— design of the conductor, i.e. determination of the diameter, wall thickness, and steel grade;
— determination of the setting depth for three installation methods, namely, driving, drilling and cementing, and jetting;
— requirements for the three installation methods, including applicability, procedures, and documentation and quality control.
This document is applicable to:
— platform conductors: installed through a guide hole in the platform drill floor and then through guides attached to the jacket at intervals through the water column to support the conductor, withstand actions, and prevent excessive displacements;
— jack-up supported conductors: a temporary conductor used only during drilling operations, which is installed by a jack-up drilling rig. In some cases, the conductor is tensioned by tensioners attached to the drilling rig;
— free-standing conductors: a self-supporting conductor in cantilever mode installed in shallow water, typically water depths of about 10 m to 20 m. It provides sole support for the well and sometimes supports a small access deck and boat landing;
— subsea wellhead conductors: a fully submerged conductor extending only a few metres above the sea floor to which a BOP and drilling riser are attached. The drilling riser is connected to a floating drilling rig. The BOP, riser and rig are subject to wave and current actions while the riser can also be subject to VIV.
This document is not applicable to the design of drilling risers.