Introduction
The offshore drilling industry is constantly pushing the boundaries of what’s possible, and the COSL Pioneer semi-submersible rig exemplifies this spirit of innovation. Built in 2012 by CIMC Yantai shipyard, this 6th generation rig was designed to tackle the most challenging drilling operations in both harsh and benign offshore environments.
Robust Design for Any Environment
With a length of 104.5 meters, width of 65 meters, and a operating draft of 17.75 meters, the COSL Pioneer cuts an imposing figure. Its displacement is a massive 36,400 metric tons when drilling. The rig’s design adheres to the stringent DNV 1A1 class notation, enabling it to operate in the harshest conditions. It is certified for drilling operations (Drill N), dynamic positioning (Dynpos-Autro), moored operations (Posmoor-ATA), heavy cranes, and helicopterdecks among other demanding activities.
Powerful Station Keeping
Station keeping is critical for any offshore rig, and the COSL Pioneer does not disappoint. It features an advanced Kongsberg Maritime DP3 dynamic positioning system with SDP-22 and SDP-12 backup. The rig is fitted with six potent 5,110 kW Wartsila azimuth thrusters providing a total 30,660 kW of thrust.
For moored operations, the COSL Pioneer has an equally robust system with eight 600m x 90mm wire mooring lines deployed by four double Rolls Royce winches. This redundancy ensures the rig maintains position even in the toughest conditions.
Mighty Drilling Capabilities
At the heart of the COSL Pioneer is its powerful drilling package tailored for deep and ultra-deepwater operations. The rig sports a massive NOV HPS 650 top drive with 590 metric ton hook load capacity. Coupled with the 4,600 HP NOV active heave compensating drawworks, it can drill to a maximum depth of 7,500 meters.
The pioneer has three NOV HEX 7,500 psi mud pumps that can pump up to 4,000 liters per minute. This high capacity system integrates 5 NOV VSM 300 shale shakers and ample storage for drilling fluids and dry bulk.
The COSL Pioneer can deploy large subsea BOP and riser stacks through its two moonpools. It has dual NOV Shaffer 18-3/4″ 15,000 psi BOPs each equipped with shear ram, annular preventers, and diverter systems. These are complemented by 50ft x 21″ Shaffer FT-E risers rated for high pressure and high temperature wells.
Superior Handling Capabilities
Efficient pipe, riser and BOP handling is key for high uptime offshore. The COSL Pioneer has an array of cranes and handling systems:
- Two 80 metric ton NOV pedestal cranes
- 20″ knuckle boom pipe handling crane with 24 mt capacity
- Two 60 mt overhead BOP cranes for each moonpool
- 300 mt BOP elevator and skidding systems
- 100 mt Xmas tree cantilever system
With these systems, the rig can smoothly run parallel drilling spreads.
Conclusion
Whether operating in the North Sea, Gulf of Mexico, offshore Brazil or anywhere else, the COSL Pioneer has the muscle, station keeping prowess and well control capabilities for the most challenging ultra-deepwater drilling programs. Its robust design is primed to operate for decades enabling ongoing resource exploration.
This powerful 6th generation rig represents the cutting edge of offshore drilling technology. As energy companies push into increasingly harsh and remote offshore frontiers, rigs like the COSL Pioneer will be indispensable assets.