Drilling the structurally complex overthrusted fault blocksassociated with the Andes foothills of Colombia has alwayspresented a number of distinctive challenges. Boreholeinstability, hard and abrasive formations, undesirable holedeviation associated with multiple fault planes and steeplydipping formations, low progress rates and frequent drill stringfailures are the most common problems encountered whiledrilling wells in the area.In order to efficiently drill a deep exploration well inColombia, the operator elected to implement its internalBeyond the Best (BtB) initiative to increase the chances ofachieving or exceeding performance goals. A strategy wasdeveloped to anticipate challenges and address criticalelements of the detailed design, the identification of theoptimum well trajectory to manage subsurface hazards as wellas continuous updates of the subsurface model while drilling.As a part of the Front End Loading requirements of the BtBinitiative, the operator elected to engage a drillingoptimization service to conduct a detailed analysis of theoverburden including a critical review of drilling performance,mud logging and wireline data from reference wells. Thisdetailed and in-depth analysis helped identify potentialproblems that led the operator to set optimization objectivesfor the upper hole sections of achieving the highest penetrationrate possible while maintaining a near-vertical wellbore. Anaction plan with recommended solutions to overcomeanticipated problems was developed and specific fit-forpurposetechnologies were identified as appropriate solutions.To introduce and build support for this new drillingphilosophy and tool implementation, the operatorimplemented the Technical Limits Process that challengedoperator and service company personnel to work as anintegrated team to achieve best-in-class drilling performanceusing the appropriate technology. The process alsoencourages trust and camaraderie between team members andchallenges them to feel personally responsible for deliveringsignificant performance improvement. The authors willdiscuss how proper planning and understanding key issues thatpreviously restricted drilling performance led to theidentification of improved drilling practices and theapplication of the proper technology that resulted inbreakthrough drilling performance including new worldrecords for impregnated and PDC bits.To measure the effectiveness of the initiatives, the authors willdocument savings relative to offset wells. The typical welldrilled in the Colombian foothills averages 188 days per10,000 feet to complete. However, by applying applicationspecific technology the team has cut the average time requiredto drill this well to 140 days per 10,000 feet with the resultantsavings in time and money to the company.
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