Drilling lags behind other industries in the implementation of automation. One reason for this is the variability of drilling operations and uncertainty in knowing what is being drilled at any given time. A closed-loop system that continually monitors drilling parameters and drilling performance in real time and constantly adjusts weight on bit (WOB) and rotary speed (RPM) maximizes instantaneous rate of penetration (ROP). The system has been tested in more than 15 drilling operations around the world in both advise and control modes. Field tests show an improvement in ROP typically greater than 10% versus nonautomated operations. Maximum benefit is realized when automation is implemented by means of a closed-loop system, whereby the set points for WOB and RPM are directly fed to the controls of the drilling rig. The algorithm, the closed-loop system, and the performance improvement delivered by this system are currently subject to certain operational constraints, but these will be addressed by future enhancements.

Accurate, quick, and reliable event detection is essential to both conventional and automated drilling processes. Methods for real-time detection of events using Bayesian inference have been described previously. These systems were initially designed to provide alarms to rig crews with little or no operator setup or maintenance. These requirements have resulted in certain limitations that restrict their use to relatively simple situations. For example, the drillstring washout detection method was based primarily on the behavior of hydraulic coefficients of a simple hydraulic model computed from standpipe pressure and flow, which meant that it was limited to only scenarios of drilling without a mud motor. New sensors and enhancements to the Bayesian inference techniques significantly improve event detection. Although applicable to a broader set of events, improvements to these detection methods can be explained using the example of a new drillstring washout detection module. The new module combines a method of detection of on-bottom drilling with enhanced signal characterization of standpipe pressure and flow to create an algorithm that can effectively handle drilling with a motor. Another improvement in the washout detection algorithm is the use of MWD turbine RPM when it is available. Unaffected by the differential pressure and depth changes, the turbine RPM data have proven to be more effective in detecting washouts occurring in the drillstring above the MWD tool. Testing both on data from several previously recorded washouts in drillstrings and on real-time data from wells with washout demonstrates the new capability of the algorithm to detect these difficult-to-characterize events while keeping false detections to a minimum.

Starting in 2004, a major service company began investigations into moving tasks normally performed on the rig to an office environment (an operations support center 1 ). These "remote operations" have evolved into a spectrum: from splitting the day and night shifts between the rig and the operations support center to complete remote decision making by the project management team for well construction. Common factors were observed and documented in the process of implementing remote operations. This led to standards and processes to support broader adoption of remote operations when they are operationally warranted. Standards and processes have been developed for change management, communications, IT infrastructure, and other issues. Case studies illustrate the spectrum of remote operations, including work from the North Sea and land operations in North America, Central America, and Russia. Two perspectives on remote operations are given. One is from the point of view of a drilling service company responsible for directional drilling and logging-while-drilling services. The second is from the perspective of a project management team contracted for the entire well construction process. Overview

Minimizing well costs and associated risks requires well construction planning techniques that account for the interdependencies involved in the well design. The inherent difficulty is that most design processes and systems exist as independent tools used for individual tasks by the various disciplines involved in the planning process. In an environment in which increasingly difficult wells of higher value are being drilled with fewer resources, there is now, more than ever, a need for a rapid well-planning, cost- and risk-assessment tool. This paper presents an automated process for integrating the well construction planning workflow and accounting for process interdependencies. The process is based on a prototype drilling simulator developed with a consortium of major oil companies in 1999–2000 that first demonstrated the technical feasibility of such a tool. The highly interactive process is encompassed in a software system thatallows well construction practices to be tightly linked to geological and geomechanical modelsenables asset teams to plan realistic well trajectories by automatically generating cost estimates with a risk assessment, thereby allowing quick screening and economic evaluation of prospectsenables asset teams to quantify the value of additional information by providing insight into the business impact of project uncertaintiesreduces the time required for drilling engineers to assess risks and create probabilistic time and cost estimates faithful to an engineered well designpermits drilling engineers to immediately assess the business impact and associated risks of applying new technologies, new procedures, or different approaches to a well design. Discussion of these points and field examples illustrate the application of the workflow and verify the value, speed, and accuracy of this integrated well planning and decision-support tool. Introduction In 2000 Schlumberger Cambridge Research completed development of a prototype software drilling simulator.1 This prototype, shown in Figs. 1, 2, and 3, was developed as part of an agreement with the MoBPTeCh consortium (a technology consortium of Mobil, BP, Texaco, and Chevron). The aim of the prototype was to offer a "proof of concept" that a simulator could address the needs of difficult well planning issues. The project demonstrated the value and viability of a tool that would provide an integrated and more automated approach to well planning. The prototype simulator was an evolution of a real-time wellbore stability concept, and it was used as a test-bed for the development of ideas that will be embodied commercially within the software system discussed in this paper.