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  • Analysis of casing while drilling shows faster drilling, higher production rates

    B. Houtchens, J. Foster and R. Tessari

    Applying a risk model to new technology is difficult because there is no experience base for quantifying either the probability of an event occurring or the consequences of the event. This is particularly true when the technology has operational components that go against normal practices such as with Casing While Drilling (CWD). Casing is used as the drillstring to solve problems that one would normally expect to be made worse by drilling with a smaller wellbore clearance, higher annular velocity and little ability to make conditioning trips. To date, Tesco’s CWD system has been used to drill more than 375 onshore and offshore wells, totaling more than 2.5 million ft in a variety of formations with different characteristics. Results of these wells in difficult drilling areas show that CWD is more efficient and encounters less trouble time than conventional drilling, saving operators time and money. The savings can be seen in daily operating costs...

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2013 Fracturing Technology

2013 Fracturing Technology