Abstract
On the Solaris Ultra-High Pressure-High Temperature exploration well drilled in the NCS in 2016, a 15.0 psi rated rig, the Maersk Gallant jack-up (MSC-CJ62-120S design), was adapted to drill a reservoir with a Maximum Expected Wellhead Pressure (MEWHP) in excess of 16,600psi.
The primary goal was to refit the rig to accept and operate in line with applicable PSA requirements, a 20.0 psi rated double BOP ram to be used in conjunction with the rig's 15,000 psi BOP. The scope included the installation of two different MPD annular pressure control systems. The modifications were to be carried out without stopping operations and within budget.
An extensive, collaborative well-planning and equipment preparation process involving the operator (client), drilling contractor and service providers was critical to the success of the overall operation. Within the drilling contractor organization, the rig team, Technical Organization, Asset Team and Operations Drilling Support worked together to ensure all requirements and risk mitigating measures were in place and lessons learned from previous HPHT/MPD operations were incorporated.
Some rig modifications were executed while in operation on another project under contract with another operator. Such jobs were limited to pulling cables and mechanical preparations to expedite hot work required at later stages.
This paper describes the key planning considerations, preparations and creative solutions deployed to deliver a complex project which culminated in successfully drilling the deepest, hottest and highest pressure well in Norwegian history. It will serve as a reference for planning future Ultra HPHT projects. No confidential operational or subsurface data is revealed in this paper.
