D&C Tech Digest
BHP Billiton-operated rigs set benchmarks for subsalt, deepwater drilling in Gulf of Mexico
BHP Billiton Petroleum announced that two company-operated drilling vessels have set new benchmarks for subsalt, deepwater drilling in the US Gulf of Mexico. On 17 May 2007, while working on a development well on the Shenzi oil and gas field, the GSF C.R. Luigs achieved a record-low average of 1.52 days/1,000 ft from spud to TD. The well was drilled to a total depth of about 26,900 ft in 33 days while operating in water depths of nearly 4,300 ft on Green Canyon Block 654.
This matches a company record accomplished the prior month on the Neptune development with the GSF Development Driller I, which averaged about 1.5 days/1,000 ft of new hole drilled. The well was drilled in less than 20 days on Atwater Valley Block 617 in water depths of nearly 6,200 ft to a total measured depth of about 17,800 ft.
The C.R. Luigs and DDI are contracted from GlobalSantaFe through 2013 and 2012, respectively.
CNPC: Horizontal well with largest displacement drilled in Quaternary unconsolidated strata
A horizontal well (Tai H5-1) drilled in Quaternary unconsolidated strata with a displacement of 1,277 m was completed in Tuha Oilfield on 11 July 2007, China National Petroleum Corp (CNPC) announced. The Quaternary unconsolidated strata are characterized by loose texture, poor diagenetic property, considerable water-taking, swellability and large debris dispersity. Well Tai H5-1 is in the central sag of New Sanhu depression in east Qaidam Basin, with a true vertical depth of 1,576 m, slant depth of 2,734 m and horizontal interval of 1,000 m. The well was drilled by No. 40667 drilling crew of the No. 2 Drilling Company of Tuha Petroleum Exploration and Development Headquarters.
Five national drilling records in Quaternary unconsolidated strata have been made by the crew, i.e., 1,009 m horizontal interval, 1,277 m horizontal displacement, maximum borehole deviation of 91.7°, 100% gas formation encounter rate and 244.5 mm casing running depth of 1,723 m.
New technologies for offshore, onshore operations
Schlumberger has released three technologies to complement WesternGeco Q-Technology services — the WesternGeco DSC Dynamic Spread Control, the Desert Explorer DX-80 vibroseis unit and the MD Sweep Maximum Displacement. For offshore, DSC Dynamic Spread Control is an automated vessel, source and streamer steering technology. It enables repeatability for 4D time-lapse studies and increase accuracy in Q enabled over/under and rich- and wide azimuth surveys. For onshore, the Desert Explorer DX-80 vibroseis unit generates an 80,000-lb peak hydraulic force with low distortion across a broad bandwidth. The MD Sweep design methodology, also for onshore, enables a vibrator to produce more energetic low frequencies than a traditional sweep design approach.
INTEQ India deploys HydroLift Full Closure System in deepwater well
INTEQ India has successfully deployed the HT60 HydroLift Full Closure System in a deepwater well. It was the single largest coring program utilizing this system to date. The coring team completed 10 consecutive coring runs using 27 m (90 ft) core barrels and Genesis design core heads. A record 258.4 m (847.7 ft) of 5.25-in. diameter unconsolidated core were recovered with 95.67% core recovery and 100% coring efficiency. The ROP using Genesis core heads was 20.10 m/hr (65.9 ft/hr). The coring program was completed on schedule, averaging almost one core run per day. The task was made more challenging with severe rig and weather conditions.
Delmar installs 100th subsea tree with HCLS
Delmar Systems recently completed the 100th subsea tree installation using the patented Heave Compensated Landing System (HCLS). Delmar has incorporated the use of the HCLS since June 2002, when it installed its first subsea tree for Shell’s Na Kika Development in Mississippi Canyon in a water depth of about 6,000 ft. This installation marked the first time a subsea tree was installed using an anchor handling vessel.
Since then, the company has also used the HCLS to install and recover various types of production and support equipment, including well jumpers, manifolds, control pods, mooring connectors, wellhead adapters and ROV tooling. “The use of the HCLS minimizes rig critical path installation activities, increase utilization of existing long-term chartered installation vessels, and accelerates development timelines,” said James Soliah, Delmar subsea manager. The effectiveness of this method is derived by reducing the heave motions at the mudline from sea conditions on surface from the installation vessel, according to Delmar.
Transocean drillship sets record for deepest drilling in Nigeria
The Transocean ultra-deepwater drillship Deepwater Pathfinder has set the record for drilling in the deepest water depth in Nigeria at 9,075 ft (2,766 m) on the Opukiri 1X well for Devon. The previous Nigerian water-depth record was 8,826 ft (2,690 m), set last year for Petrobras on its Kiniun 1X well by the Transocean ultra-deepwater drillship Deepwater Discovery.
“Congratulations are certainly in order for achieving the water-depth record in Nigeria,” said Thomas Hinterseer, Gulf of Guinea division manager. He added that the Nigerian record comes on the heels of crews’ excellent work on the BOBO-2 well for Shell Nigeria Production Company (SNEPCO).
On BOBO-2, crews constructed the 8 ½-in. section almost 75% faster than normal, with 2,086 ft drilled in 24 hours. The time savings mainly came from improved back reaming, surveys, flow checks and making connections, explained rig manager Chijioke Akwukwuma. “The connection times on the section were essentially completed in half the average time for the rig,” he noted. “I am very proud of this performance and look forward to applying what we have learned on the BOBO-2 well to other assignments.”
The client also praised the crews’ achievements on the BOBO-2 well. “We achieved a hole which is the best that I have seen since arriving in Nigeria,” said SNEPCO drilling superintendent Mark Ratchinsky in a note of congratulations.
Weatherford takes step forward in well logging
Ten years after the initial development of the Compact well logging system, Weatherford is celebrating a milestone of 250 systems now built. Its 40th Compact Micro Imager (CMI) has eight metal pads that create 176 measurement points, which enable the CMI to produce almost photographic images downhole covering 96% of the wellbore. CMI images allow clients to identify rock strata and producing zones, and see dips and faults in the reservoir. More than 100 wells have been completed using the CMI, with strong results, according to Weatherford. The company has also successfully logged two wells using the CMI with the memory logger and the shuttle system. Use of the shuttle represents a big step forward because it allows for horizontal well operation, a difficult task with traditional imaging tools.
Trial wells successful for Kuwait Oil Company
In the Burgan Field for Kuwait Oil Company, PathFinder Energy Services successfully drilled two trial wells using directional drilling equipment, including Dyna-Drill drilling motors and the PathFinder HDS-1 MWD-Gamma Ray tool. Kicking off the well from vertical at 850 ft, the team built to a 28° inclination at 297° azimuth, then held as planned. They then brought the well to vertical again at a depth of 3,648 ft. The team drilled from 850 ft to 3,648 ft for a total of 2,798 ft in 86.5 hrs on bottom with an average ROP of 32 ft/hr. A 9 5/8-in. F2000MX Dyna-Drill motor and HDS-1 Gamma Ray tool were used.
Saudi Aramco, Schlumberger to develop borehole gravity metering technology
Saudi Aramco and Schlumberger are jointly developing a new borehole gravity metering (BHGM) technology to measure the movement of deep-reservoir fluids at a precision scale never before attained.
“Collaboration with service providers is one of our approaches to develop the next-generation tools that meet our needs. This is another example of this philosophy,” said Amin H. Nasser, VP of petroleum engineering and development at Saudi Aramco.
Schlumberger and Saudi Aramco are jointly developing a new, high-precision, slim-hole BHGM logging tool, with the associated sensors that will acquire gravity density measurements through 4 ½-in. outer-diameter tubing, without having to pull out the tubing strings. The resulting measurements will require inversion software to be developed to help estimate reservoir fluid saturations to make accurate interpretation possible deep into the reservoir.