Real-Time Drilling-Process Optimization

Abstract

This article, written by Assistant Technology Editor Karen Bybee, contains highlights of paper SPE 119650, "Real-Time Optimization of the Drilling Process - Challenges in Industrialization," by E. Cayeux, SPE, E.W. Dvergsnes, SPE, and F. Iversen, SPE, International Research Institute of Stavanger, originally prepared for the 2009 SPE/IADC Drilling Conference and Exhibition, Amsterdam, 17-19 March. The paper has not been peer reviewed. A new drilling-control system for real-time optimization and automation has been developed in an ongoing research project, which now will enter an industrialization phase. The system, which is based on application of advanced real-time process models for calculation of both hydraulic and mechanical forces, requires an extensive set of input data. Results from the calculation modules are applied directly in the drilling-control system, affecting parameters such as pipe acceleration, velocity and deceleration, and the pump-startup profile. Introduction During the last decade, computer-controlled machinery have made it possible to control the drawworks, the topdrive, mud pumps, and the iron roughneck or pipe-handling equipment from a drilling workstation by use of joysticks and keypads. Recent developments enable control of the machinery within safe-guard boundaries through application of model simulations, accounting for the effects of fluid and pipe movements in the wellbore. These new extended systems have the potential to reduce the risk of damaging the well and the downhole equipment and, subsequently, to reduce nonproductive time. For such extended systems to function properly, a more precise description of the drillstring components is required to calculate pressure losses, mechanical loads, and heat transfer. Furthermore, complete descriptions of the wellbore architecture, formation prognosis, trajectory, and drilling-fluid properties are needed for configuration of the applied models. Most of this information is not available in standard rig systems, and no standard work process has been established to make this information available before actual operations. For such systems to achieve their full potential, the necessary information must be quality controlled and made available at the right time, because an error in this information could lead to potentially serious incidents. In January 2008, a field test of a new system for automated control of the drilling process was performed on the Statfjord C platform in the North Sea. Because the system was developed through a research project, the focus up to now has been on robustness. The system now is entering the industrialization phase, with a stronger focus on system application, including the following.Sensor quality and reliability.Availability of wellbore description including information exchange between different systems.Work processes for updating well bore description and quality control of data.User friendliness.Personnel training.