Two safety valve depth records
Subsea completion tree systems at a water depth of 7,200 ft set a world record. Another record was set for safety valve installation at 9,828 ft. The records were set on the first well of the six-well Canyon Express development project in the Gulf of Mexico. The new SenTREE 7 record extends the previous Schlumberger world water-depth record of 6,400 ft set in January 2000 in the western part of the Gulf of Mexico. The previous safety valve record was an installation at 8,934 ft.
The modular design system is used in conjunction with horizontal tree systems and allows live wells to be controlled under a variety of well conditions and operational circumstances using real-time data. For this Gulf of Mexico well, the service was performed from a dynamically-positioned vessel.
The new 3- to 7 3/8-in. subsea completion is pressure rated to 15,000 psi, temperature rated to 350°F and is capable of operating in water depths to 10,000 ft. Using advanced control system technology, the system can operate from either anchored or dynamically positioned vessels.
A TRC-DH tubing retrievable safety valve, due to its numerous material and design options for precise matching of operating parameters to actual well conditions, has become a standard component in most deepwater and ultradeep wells. The valve is found in 75% of all wells in 1,000 ft or more water depth.
Flow-activated circulating tool
One of Europe's leading independent oil service companies, the UWG Group, has introduced its flow-activated circulating tool, designed to improve the cost-effectiveness of offshore wellbore clean-up operations. The tool, which has been subjected to extensive function testing and field trials, relies on a simple pump open/pump close mechanism and was developed in response to concerns regarding the operability and performance of existing "drop ball" and "weight set" tooling options.
The pump open/pump close mechanism ensures there is no limit to the number of cycles the tool can perform and, critically, provides a way of confirming the tool's position. Following data gathered during field trials and previous operations, a number of improvements have been incorporated into the tool configuration, resulting in a piece of technologically advanced equipment that can deliver consistently reliable results across a wide range of applications.
The tool is run in the bottom-hole assembly at a predetermined distance above the drill bit to provide the option of diverting circulation away from the bit and through a communication port to the drilling annulus.
Also, it can be used during both drilling (open hole) and circulation (cased hole) operations to provide increased circulation and flushing rates to remove cuttings prone to settling in large hole diameters.
A comprehensive engineering support incorporating a predictive analysis software package for optimum tool placement in the string and mud rheology comparisons is available.
The tool is used in conjunction with already existing tools offering an alternative and cost-effective source of service provision for wellbore clean-up operations.
Compact well shuttle
A new deployment system for safe, fast deployment of open-hole logging tools into high angle/horizontal wells and wells with bad hole conditions has been developed. Reeves Oilfield Services recently introduced this system, called the Compact Well Shuttle.
This is a hybrid deployment system for compact, open-hole logging tools. The tools are contained at surface inside drill pipe where they are fully protected while running into the well. They are released into open hole only when the system nears bottom, after which they remain anchored to the pipe and acquire data on the way out.
The system does not use a wireline, so it runs-in at tripping speed. Pipe can be rotated and reciprocated to assist in reaching bottomhole, and circulation can be maintained to help clean the hole and control the well. Logging can be integrated with a wiper trip to further reduce rig time.
The system claims to replace wireline pipe-conveyed logging (PCL) in high-angle wells and provides an efficient alternative to logging while drilling in wells that can be drilled without real-time formation evaluation. It is also an intervention technique delivering formation evaluation data when other logging solutions have failed.
In 2001, this system successfully completed a nine-month program of trials in the 1.4-km large flow loop facility at the research labs in East Leake, UK, and in the horizontal test well at the downhole technology center in Aberdeen, UK.
Following delivery of the system in late December 2001, it was deployed in Western Canada where it has successfully completed its first month of commercial operations, demonstrating substantial savings in rig time.
The first two operations - for Husky Energy and Anadarko Canada Corporation - were in high-angle wells. In the first well, the shuttle was deployed to 10,200 ft, and 1,864 ft of triple-combo data was recorded covering a horizontal interval from total depth (TD) to casing shoe. TD bit size was 6.25 in.
The second well was drilled to 90° deviation at 4,019 ft. The system was deployed close to TD from where data was recorded across the build section back to casing shoe at 607 ft using a quad-combo measurement stack (gamma, photo-density, neutron, array induction, sonic). On this occasion, the TD bit size was 7.875 in.
The conventional logging solution in these wells is wireline PCL. However, this system saved 13 hours of rig time for the first well and 16 hours for the second well, representing reductions of 43% and 67% respectively. Multiple wet-connects were avoided in the second well by using the new technology.
The system allowed both operators to meet their formation evaluation objectives safely and reliably and at a substantially lower total cost relative to PCL. The efficiency of this logging operation was easily measurable in terms of rig time savings. The simplicity of the operation was quite evident with the elimination of the wet connect.
This system has now been deployed for other Canadian operators, including ExxonMobil Canada, and is due to begin operations in the US, Europe, and Asia Pacific.
Solid expandable technology
Enventure Global Technology, the creator of solid expandable technology (SET), continues to set new standards in well construction to increase production rates and reduce costs on each well. To date, 53 expandable systems have been installed onshore and offshore, domestically and internationally, for major oil companies and large independents, including Shell, ExxonMobil, BP, and Anadarko. Additionally, a total of 43,837 ft of tubulars and 1,148 proprietary connections have been expanded.
A recent milestone includes the first installation of the SlimWell, or "nested," System in the Chesapeake Wellman 3-H well in South Texas in June and July 2001. An expandable 5 1/2 in. to 7 5/8 in. openhole liner (OHL) was installed inside a 6 in. to 7 5/8 in. previously expanded OHL System, minimizing the reduction of hole size at TD. The ability to successfully nest expandable systems means deepwater wells can now be downsized as can the size of the drilling vessels required to drill wells in water depths exceeding 5,000 ft.
In October 2001, ExxonMobil successfully expanded 2,060 ft of 6 in. to 7 5/8 in. OHL in a well in deepwater Gulf of Mexico at a depth over 22,000 ft. This resulted in the deepest SET installation.
The highest-angle SET installation occurred in October 2001 in a horizontal sidetrack for Shell Production and Development Co. of Nigeria. A 1,659 ft, 5 1/2 in. OHL System was expanded into 7 in. casing in an interval spanning angles from near vertical to a horizontal landing point. This OHL system is expected to increase production of this well over 30% compared to conventional practice.
