This reference is for an abstract only. A full paper was not submitted for this conference.
At the conceptual stage of planning an extended reach well, some of the most crucial aspects include effective hole cleaning/cuttings transport, torque and drag, hydraulics and flow rates. With this in mind, one of the most important considerations is the rig itself. In an ideal world, the rig would be designed and equipped for extended reach drilling (ERD) operations, with the appropriate mud pumps, top drive, power and circulating systems at the top of the wishlist.
In the real world however, modestly powered and equipped rigs are being contracted to drill increasingly complex and demanding wells. Only through innovation and careful planning can these deep, extended reach targets be met. Key elements in ERD planning include:
Drilling fluid design
Up-front hydraulics modelling
Drill string and BHA design
Rig power distribution
Clear methodology for drilling and tripping practices
Good teamwork across the rig and onshore teams
During the execution of the drilling process, close monitoring of specific areas can provide a good indication of potential problems. The most critical parameters are:
Hole condition monitoring
Equivalent circulating density (ECD) interpretation
Hole cleaning and hole cleaning evaluation software
Torque and drag trends
This study discusses what action can reasonably be taken to push the capability of a given rig beyond what would normally be expected from it. The discussion is based upon an ERD well drilled offshore Brunei from a jack-up rig to a total depth of 6,642m (2,800m TVD) in 8' hole, with 9 5/8" casing set at4,951m (2,800m TVD), both of which, although modest in global terms, were records for Brunei.