Drill string telemetry technology allowing reliable data transmission at speeds up to 57,600 bits per second has recently been utilized on two separate offshore locations in the Norwegian North Sea. The results from these deployments prove that a reliable technology exists for high-bandwidth, bi-directional communication between the downhole sensors and surface. This technology overcomes the existing industry challenge related to low bandwidth and time lag associated with mud pulse telemetry. The drilling industry is facing substantial challenges as the remaining petroleum reserves are found in more and more complex environments. Slow overall drilling progress and considerable time and costs related to unproductive time are often seen in the challenging wells needed to tap these reserves. The traditional way of controlling the drilling process seems to have reached its limits. The high-speed telemetry drill pipe technology gives access to large amounts of high-resolution data in real-time. The data can be divided into two main groups drilling process data and formation evaluation data. This paper will primarily focus on the drilling process data and how downhole data can be used in real-time to improve the drilling process. Further, the paper will discuss several drilling operations which can be significantly improved by using high-resolution data in real-time. Short- and medium-term potential benefits will be considered. Required further development of the technology will be discussed together with its practical applications. The paper will also focus on how drill string telemetry technology will be a key enabler for future coupling between downhole sensors and surface control systems. This will open up for more automation of the different drilling processes and a real step change in drilling process control. Introduction The need for major improvements in the drilling industry is urgent. The worlds need for energy is increasing while the remaining oil and gas reserves are more and more challenging to exploit, both from a technical and economical point of view. to mention a few. Major oil provinces in the Middle East, North Sea and North America have been producing for many decades. Large reserves still remain in the ground, but it will require a lot of new wells to fully exploit these remaining reserves. IOR reserve is a commonly used term. The industry is facing a challenge in providing sufficient drilling capacity to exploit these reserves. In most cases, there will be a direct function between the production rate and the drilling capacity on a field. The same will be the case for the ultimate recovery on a field. Low ability to drill new drain holes in the reservoir will leave reserves in the ground that could have been exploited with increased drilling efficiency.

The demand for increased oil and gas recovery requires the drilling of complex extended reach wells with optimized reservoir exposure for production and minimized overall production costs. In order to achieve these objectives, the use of high-end drilling and logging technology to optimize well placement is of the essence. However, the optimal utilization of this technology is often limited by the real-time transmission bandwidth of essential data from and to the downhole tools. The introduction of wired drillpipe technology has facilitated a step change in two-way data communication resulting in a high-speed data transmission giving much greater volume, resolution and quality of formation evaluation data and drilling dynamics data. Furthermore, the direct control of rotary steerable tools has now been enhanced to allow instantaneous programming changes and better utilization of dynamics data to enhance the decision making process required to address drilling dysfunction challenges, hole quality, gross ROP and BHA reliability. The high bandwidth technology was used while drilling two laterals on the Troll field's reservoir in the Norwegian North Sea in 2007. The memory quality data was transferred through wired drillpipe to the surface while geosteering through relatively unconsolidated sandstones with localized zones of hard calcite cementation. The bottom hole assembly employed, comprised multiple formation evaluation and dynamics sensors to fully understand the downhole drilling conditions. The data was transferred to the expert advisory centre onshore for advanced processing and interpretation to enable the critical decision making process. The adoption of a Total Systems Approach to select the ideal combination of application-specific drill bit, drilling system, and appropriate procedures and practices was presented and described by Stavland, et al (2006). Realizing the full benefit of the approach has been hampered by bandwidth restriction and time lag associated with conventional mud pulse telemetry. This paper will discuss how wired drillpipe technology has been utilized to enhance the Total System Approach concept during the first tests and how it will affect operations going forward. Introduction Telemetry Drill String Technology Overview First used in 2003 and commercially launched in 2006, the broadband network used in this application offers an ultra high-speed alternative to current mud pulse and electro-magnetic telemetry methods. The network utilizes individually modified drilling tubulars to provide bi-directional, real-time, drill string telemetry at speeds upwards of 57,000 bits per second. This greatly enhanced band-width in comparison to existing technology makes it possible to obtain large volumes of data from downhole tools (and other measurement nodes along the drill string) instantaneously, greatly expanding the quantity and quality of information available while drilling. The network utilizes a high-strength coaxial cable and low-loss inductive coils embedded within double-shouldered connections in each tubular joint to convey information. Currently available telemetry tubulars include various sizes of range 2 and range 3 drillpipe, heavy-weight drillpipe, drill collars, and a wide array of bottom hole assembly components (API Spec. 5D).

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TX 75083-3836, U.S.A., fax 1.972.952.9435. AbstractEconomical demands within the oil and gas industry are the driving force to exact significant advances in Drilling and Formation Evaluation Technology. This has been exemplified by the application of new technology to address the complex challenges of the Troll Field Reservoir in the Norwegian North Sea.Exploiting the Troll reservoir requires horizontal geosteering through relatively unconsolidated sandstones with localized zones of hard calcite-cementation. Optimum well placement is of the utmost importance and demands reduced tolerance for any inaccuracy within the thin oil reservoir column throughout the progressively increasing drained hole section. Consequent to the advancement in drilling technology, the horizontal reach has been extended from some 500 meters to more than 5000 meters in a single reservoir section including horizontal turns of up to 360°.In 2001 an innovative service was introduced to the Troll field, being founded on a new multi-sensor data acquisition and processing Measurement-While-Drilling (MWD) tool. The downhole tool contains various dynamics and mechanical sensors, and a high-speed data processing system to continuously provide an accurate picture of the downhole conditions and the energy transfer train. The service was deployed to optimize the mechanical efficiency of the drilling process by facilitating the immediate response to differing situations encountered while drilling complex heterogeneous formations. This real-time service, but also the intrinsic detailed studies on BHA and bit design with ensuing in-depth knowledge capture have lead to a comprehensive understanding of the Troll drilling challenges and thereby facilitated the design and utilization of application specific bottom hole assemblies with associated relevant drilling procedures and practices. This paper will discuss how this technology is used and how this total drilling system deployment concept has been applied to successfully surmount the specific challenges of the Troll Field.

fax 01-972-952-9435. AbstractDrill string telemetry network technology allowing reliable data transmission at speeds up to 57,600 bits per second has been utilized in many land based drilling applications.The drill string telemetry network incorporates a highstrength data cable that runs the length of each tubular joint. The cable terminates at inductive coils that are installed in the secondary torque shoulder of each connection. As the drill string is assembled, the inductive coils in adjoining tubulars are brought close together allowing data to flow across the connection. The network signal is boosted occasionally by repeater subs, which also provide locations for along-string temperature measurements. The technology offers robust, reliable operation and is virtually transparent to standard rig procedures.In 2007, the Troll field in Norway saw the first commercial deployment of this technology into a complex offshore multilateral drilling project.This paper details the lessons learned and value derived from the use of an ultra-high speed drill string telemetry network and compatible rotary steering, drilling dynamics and advanced formation evaluation measurement tools while drilling multiple laterals of an extended reach horizontal well from a semi-submersible drilling rig.Of particular focus will be discussion of the specific value gained from: real-time analysis of high resolution dynamics and inclination measurements to instantly manage the drilling transition between relatively unconsolidated sands with imbedded hard calcite-cemented stringers; instantaneous network-enabled surface control of rotary steerable tools to eliminate non-productive time and improve directional control; real-time transmission and interpretation of highvolume, memory quality formation evaluation measurements to improve geological well placement; and non-productive time elimination resulting from the availability of full telemetry redundancy.The paper includes comment and perspective from the Troll field operator regarding the immediate value and likely future utilization of telemetry drill string technology.