Improved Drilling Efficiencies Using Offline Cementing Saves Days on Welland Reduces Costs

摘要

Drilling in the Appalachian basin in Pennsylvania has evolved since its inception.Operators have shiftedtheir focus from mere wellbore delivery to delivering wells in the shortest amount of time to reduce risksand costs,as well as drive efficiency.This paper presents a case study in which offline cementing helpedimprove operation efficiency by reducing drilling times and provided significant cost savings.Offline cementing is not a new concept.In Q4 2015,an operator drilling in the Eagle Ford shale beganthe movement of their program toward offline cementing of both the surface and production casings.The operator determined that reducing flat time was crucial to create a cost savings(Hsieh 2018).Whenanother operator began their 2018 drilling program in northeastern Pennsylvania,improving efficiencies wasdiscussed with the service company.After quantifying the experience obtained during a previous project,the service company proposed offline cementing because of the economic benefits it could provide.The service company was able to cement both the surface and intermediate casing strings offline whilethe operator skidded to the next well to begin rigging up.All surface casings were drilled and cementedoffline and the rig skidded back to drill for the intermediate casings,which were also cemented offline.Approximately 15 hours was saved by skidding between surface strings,and another 16 hours was savedbetween intermediate casings.This paper discusses the successful use of offline cementing during drilling operations in northeasternPennsylvania.The flat time reduction achieved during this drilling program can be quantified into a costsavings of approximately USD 80,000 per well.