Advanced Design and Execution Techniques for Delivering High Data Rate MWD Telemetry for Ultradeep Wells

Abstract

Abstract Description. The purpose of this paper is to describe innovativeimprovements to mud pulse telemetry in an ultra deep environment. This alignstelemetry services with the customer need to enhance drilling performancewithout data quality sacrifice through mud pulse technology, providing thecapability of drilling to 15 km and beyond. Application. The MWD pressure pulse signal suffers attenuation anddegradation while traveling uphole. Echoes and reflections, drill pipe IDchanges, pulsation dampener type and mud plastic viscosity, attenuates thepressure signal up 95% as it reaches surface. Planning becomes keystone for thetelemetry system where;–Quantification ofsignal attenuation enables a risk managed planning.–Hardware, improvesMWD Signal detection capabilities.–Software, allowspractical transmission and bandwidth utilization Results. This effort resulted in the development of comprehensivemodels for the telemetry signal; as it evolves with depth and is affected bythe different elements of the drilling system.–Integratingenhancements in software and hardware resulted in doubling of MWD transmissiondata rates.–Application ofcompression schemes increasing up to 7 times effective transmission speeds. Significance of subject matter. Successful drilling of deep wellsrelies heavily on the planning stage, to extract the maximum value from thedrilling investment. The initiatives outlined in this paper expand theoperating envelope of the more applicable telemetry technology, supporting thenew depth limits to be set. The effort of this investigation delivered areliable, high band-width transmission system designed for wells targeting 15kmreach and beyond. Introduction Arctic environments hold a big share of the world oil and gas reserves, locations where drilling performance and cost efficient operations become thekey factor for a successful drilling campaign. Several operators have adoptednew drilling capabilities to achieve production on geographically challengingreservoirs. Proliferation of extreme extended reach drilling wells increasedthe demands of reliable and enhanced mud pulse telemetry systems, aimed tosatisfy the new oilfield milestones.