Improving Drilling Performance Through Systematic Analysis of Historical Data: Case Study of a Canadian Field

Abstract

Drilling operations daily generate large amounts of data but surprisingly, a significant proportion of these data are not utilized in a manner that shortens the learning curve and promotes drilling efficiency. The authors, through this paper, demonstrate how drilling analysis methodology helped identify performance gaps in a West Central Canadian field. The above is captured under the much espoused philosophy characterized by the questions:Where are we now?What is possible?How do we get there? By applying this tool, significant cost savings to the tune of CAD$7.3 mln have been achieved as at the time of preparing this paper. Introduction There have been various approaches developed over the years to optimize the well construction process but only a few of these have addressed the subject of improving drilling performance through a systematic analysis of historical data. The drilling analysis concepts described in a companion paper1 were applied to an already optimized field and additional cost savings of 15% were realized as at the time of preparing this document. The driver to the adoption of drilling analysis as a core requirement was prompted by the requirement to reduce drilling cost as a way of improving project economics in the matured sedimentary basins of Western Canada. At the commencement of drilling analysis in the Wild River Field, a total of 41 gas wells have been drilled by Anadarko and its predecessors since the first well was spudded in 1999. Thirteen of these wells were drilled to between 5 and 20 degrees deviation while the rest were drilled as vertical wells with maximum allowable deviation of 2 degrees. Hole sizes and casing schemes were largely similar (Fig 1). The surface holes were drilled with 311 mm bits to about 430 m while the production holes were drilled through the reservoir (Cadomin) to TD in the Fernie formation at 3050 m. The wells, from spud to rig release, were initially drilled between 56 and 70 days at the onset of field development, but with more wells drilled, drilling operations time improved and flattened at between 22 and 38 days, averaging 29 days for well depths of approximately 3050 m (Fig 2). The well cost associated with the drilling of these wells also improved from CAD$2.50 - CAD$3.75 mln (in money of the day terms) at the beginning of field development to an average of CAD$1.76 mln (or $570/m) before performing drilling analysis. The public domain data from 40 other wells drilled by 4 other operators in the Wild River field were also studied and the drilling time results showed similar performance level as Anadarko's (i.e spud to rig release time of 30 days, Fig A-1).

Drilling Performance: Efficient Integration of the Entire Drilling System

“…Most importantly, knowledge of where the connections or touch points exist between the different domains is essential so that the implications of a change to the system can be rapidly assessed by the entire engineering team and service providers to help ensure the overall goals are met. The approach is novel within the industry because of the scope of the workflow, which encompasses all engineering relationships while drilling the well; whereas previous work tended to focus more on optimizing real-time behavior to respond to conditions encountered, using reservoir simulators to plan developments, or has been limited to collaboration between only two or three disciplines (Brett et al 1986;Adeleye et al 2004). …”

Estudo da influência da taxa de penetração de broca de perfuração nos custos da construção de poços de petróleo

“…6 Devido à importância dessa área, tal assunto pode ser visualizado em diversos trabalhos como, Adeleye et al (2004), Nakagawa et al (2005) e Iyoho et al (2005).…”

“…De acordo com Adeleye et al (2004) há uma subutilização de metodologias para análise de dados quando se trata de promover a eficiência das operações. Os autores acreditam que apesar de existirem muitos trabalhos desenvolvidos que apresentam métodos para otimizar o processo de construção de um poço, poucos deles tratam desta melhoria através de uma análise minuciosa dos dados de perfuração.…”

“…Figura 2.1. Diagrama relacionando os tempos de duração para perfuração de um poço (Adeleye et al, 2004).…”

“…Através dessa análise, Adeleye et al (2004) mostrou ser possível se ter uma idéia do desempenho das atividades executadas, identificando quais podem ser melhoradas (ou seja, ter seu tempo de duração reduzido), e estabelecer, assim, um objetivo comum de desempenho para as próximas operações. Tal análise consiste, basicamente, do levantamento dos tempos de operação como perfuração (tempo de broca no fundo), manobra e manuseio de ferramentas, operações de BOP e cabeça de poço, assentamento de revestimento e cimentação, perfilagem de avaliação e testemunhagem.…”