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Intelligent drill string components capable of transmitting data at rates up to 2-megabits per second have been developed and successfully tested in commercial drilling applications. This paper details the lessons learned during intelligent drill string field trials, with focus on the overall network performance during drilling operations, physical handling ease and integration of existing down-hole measurement tools into the network. This is the first publication of information from such field trials, and the first discussion of down-hole tool data transmission through the intelligent drill string network. The paper includes discussion regarding the potential impact of intelligent drill string technology on the drilling and completion process. This new technology can improve well productivity, reduce drilling time/costs and enhance well control safety. The paper addresses these issues and provides a forward-looking view regarding large-scale introduction of the system and the anticipated time-line for commercial availability. The intelligent drill string system incorporates a high-speed data cable protected in a high-pressure conduit that runs the length of each joint. The cable terminates at inductive coils that are installed in grooves machined in the secondary torque shoulders of double-shoulder connections at each end of the joints. The system's design supports high-speed, high-volume, bi-directional data transmission to and from hundreds of discrete measurement nodes. As a result the system offers an opportunity to capture critical data along the full length of a drill string, not just at the bit, in addition to supporting the use of high-resolution LWD tools and providing instantaneous control of down-hole mechanical devices. The system offers robust, reliable operation and is virtually transparent to standard rig procedures. Introduction Mud pulse telemetry is the current industry standard for transmission of data from MWD and LWD tools to surface and typically functions at 3 to 6 bits/sec, rising to 12 bits/sec under ideal conditions. These relatively low data rates force multiple sensors to compete for bandwidth, limiting data density and demanding complex downhole processing systems in order to achieve modest real-time measurement resolution. Mud pulse telemetry presents several other significant barriers to data flow during the drilling process:A limited capability to receive commands from surface often results in significant non-productive time when changes in down-hole tool functionality are required.The requirement that all sensors be in close proximity to the mud pulse tool prevents distributed measurements along the drill string.The inability to transmit data when circulation stops can leave the driller blind during well-control situations. Seven years of engineering and development, funded in part by the U.S. Department of Energy, has produced an intelligent drill string network capable of transmitting data at rates up to 2 Megabits/sec. This system makes it possible to obtain large volumes of data from existing MWD/LWD tools instantaneously - greatly expanding the quantity and quality of information available in ‘real-time’. In addition, the system design means data can be transmitted both upwards and downwards, from hundreds of distributed measurement devices, regardless of circulation conditions. Each device can be defined as a node with a unique address and can gather or simply relay data from a previous node onto the next. Network protocol software and hardware control the flow of information between devices. Since every node is uniquely identifiable, the location where events occur along the length of the well can be determined. The system's bi-directional communication architecture means not only is high-speed transmission of downhole data to the surface possible, but also commands from the surface to devices downhole or even between downhole devices can be sent, received and acted on.

Maersk Olie og Gas AS as operator for the Danish Underground Consortium (DUC) has successfully planned and delivered an Observation and Monitoring well in the Halfdan field located in the southern part of the Danish North. Although not entirely unique to the industry (for further examples see Richardson, 1977 1 ; Widmyer, 1987 2 ;Wannell & Ezekwe, 1992 3 ) this will be the first well of its kind for Maersk Oil and the DUC placed in a chalk reservoir. This paper describes the planning and execution phases of the monitoring and observation well legs, summarizing the formation evaluation results primarily related to remaining oil saturations. The data derived from the evaluation program enables an evaluation of the success of the novel wells pattern design in the Halfdan field, enabling optimization of the reservoir recovery, in addition to confirming the vertical extent of the hydrocarbon column.As oil and gas fields mature, the monitoring of production-induced changes becomes crucial to sustain, optimize, and improve production levels. Enhanced recovery techniques are applied to extend the field life, as a result reservoir behavior, including vertical and lateral sweep, becomes more complex and challenging to model. Water injection is a common practice used to maintain the reservoir pressure and enhance oil sweep; yet sweep efficiency is not always equal, with water tending to move heterogeneously through the reservoir seeking higher permeability pathways and leaving trapped/un-swept oil behind. The fluid movement and distribution within the reservoir characterises the efficiency of the production system. Such inherently complex and capital intensive nature of understanding and optimising the recovery mechanism behoves the developer to acquire information to evaluate and enhance the recovery mechanism targeting maximising returns.Monitoring and Observation wells allow the detection of in-situ fluids, enabling modification and enhancement of the dynamic modelling, assist with evaluation of the applied IOR technique, and lay the foundation for potential future EOR opportunities. The two-pronged well provides an early indication of the recovery mechanism success in terms of sweep efficiency, and is a guide to further performance optimisation; additionally it is an opportunity to identify and develop any un-swept volume.The Halfdan field is situated in the Danish North Sea Central Graben approximately 250 kilometers off the West coast of Denmark, and is located between the Dan and Skjold fields. The Halfdan reservoir is Maastrichtian and Danian aged chalk characterised with relatively high porosity (25-35%) and low permeability (0.5-2 mD). Halfdan was discovered in 1998 with a 30,000 ft long horizontal well drilled from the Dan field. The first vertical well was completed in 1999. First production from Halfdan was obtained in late 1999.A slant observation and monitoring well on the Halfdan field was drilled between neighbouring injector and producer horizontal wells respectively, the first such well in the Danish Nor...

Objectives/Scope Drilling operations rely on the collaboration of many participants, and the efficiency of this collaboration depends on timely exchange of information. The complexity and variability of this information make it difficult to achieve interoperability between the involved systems. Recent industry efforts aim at facilitating the many aspects of interoperability. A central element is semantic interoperability: the ability to correctly interpret the real-time signals available on the rig. This contribution presents an implementation of semantic interoperability using OPC UA technology. It translates the principles developed through joint industry efforts into actual drilling operations. Methods, Procedures, Process The process used the steps of characterizing the drilling real-time data with semantic graphs, and then developing methods to transfer this characterization to an operational real-time environment. A semantic interoperability API (application programming interface) uses the semantic modelling capabilities of OPC UA. Its objectives are to facilitate the acquisition and identification of real-time signals (for data consumers) and their precise description (by data providers). The different components of the API reflect the diversity of scenarios one can expect to encounter on a rig: from WITS-like data streams with minimal semantics to fully characterized signals. The high-level interface makes use of semantical techniques, such as reasoning, to enable advanced features like validation or graph queries. Results, Observations, Conclusions The implementation phase resulted in a series of open-source solutions that cover all the stages of semantic interoperability. The server part integrates real-time sources and exposes their semantics. Data providers can use dedicated applications to accurately describe their own data, while data consumers have access to both predefined mechanisms and to more advanced programming interfaces to identify and interpret the available signals. To facilitate the adoption of this technology, test applications are available that allow interested users to experiment and validate their own interfaces against realistic drilling data. Finally, demonstrations involving several participants took place. The paper discusses both the testing procedures, the results and insights gained. Novel/Additive Information The solutions described in this contribution build on newly developed interoperability strategies: they make on-going industry efforts available to the community via modern technologies, such as OPC UA, semantic modelling, or reasoning. Our hope is that the adoption of the developed technology should greatly facilitate the deployment of next generation drilling automation systems.