Continuous development of drilling technology has enabled the oil and gas industry to drill deeper and more complex well paths. Drilling dynamics measurements have been the dominant contributor to rate of penetration maximization, overall drilling optimization and downhole assembly reliability assurance for more than three decades.
A consequence of today's complex downhole assemblies and well paths are higher downhole forces and vibrations. These conditions require more quality drilling dynamics information than before for safe and efficient drilling. Driven by this demand, new developments in downhole and surface equipment have made available larger amounts of drilling dynamics data with higher sample rates. In parallel, development of reliable high-speed telemetry allows the high-resolution drilling dynamics data to be utilized on surface to deliver answers while drilling. These developments were made possible due to the recent advent of high-performance downhole-capable electronic technologies, as well as the availability of increased computation power for signal processing at the rig site.
This paper describes improvements in the drilling dynamics measurement systems to overcome the challenges imposed by deeper and more complex wells. Gathering, processing and transmitting drilling dynamics data at high rates introduces challenges due to tighter downhole sensor requirements, the required digital signal processing power, amount of available memory, electronics temperature tolerances and telemetry requirements. Optimized hardware design, signal processing and enhanced telemetry sequences and methods are answers to these challenges, to ensure the adequate performance of drilling dynamics measurement systems. These improvements allow a fast response to new drilling conditions, the adjustment of drilling parameters to changes in formation, and a rapid evaluation of drilling performance. This enables field personnel to make decisions focused on drilling optimization, and these case histories are added to advance drilling optimization best practices.
The drilling dynamics measurement system described in this paper has been successfully run in challenging fields in the North Sea and Middle East. Compared with offset runs, the system has significantly increased data quality and sample rate and provided, in addition to industry-standard-measurements, unique measurements for the identification and mitigation of high-frequency torsional oscillations. Examples of the improved capability and operational performance are provided.
This paper also highlights changes necessary to further improve drilling dynamics measurement systems for evolving real-time drilling optimization needs.