Innovative Drilling Systems for Kick-off, Curve Building and Landing a Lateral without Requiring Cement Plug

Abstract

AbstractHistorically, the predominant sidetracking methodology for kick-off and subsequent curve building operation required setting a cement plug followed by using a directional BHA to drill deviated hole once the cement hardens. The success of the cement plug depends upon formation compressive strength, downhole temperature and pressure, wellbore deviation, cement plug depth, quality of cement and the plug cure time. The consequences of cement plug failure are extra trip time, a new cement plug, loss of drilling days and reconfiguration of drilling trajectory.Recent R&D efforts have identified new methods and associated tools that can be effectively utilized to increase operational reliability in kicking off, subsequent curve building and landing a lateral without the cement plug in varieties of formations. This paper presents innovative drilling systems that can be deployed, azimuthally oriented, hydraulically set and configured to initiate drilling, all in the same trip downhole without the need for a cement plug.The system includes:A directional BHA which may include a rotary steerable system, a positive displacement motor or a turbo-drill A roller cone or a PDC or an impregnated drill bit selected for the formation with appropriate attachment mechanism A built-in deflector ramp for attachment with the drill bit and for maximum support and guidance to the directional drilling BHA A formation specific, expandable and hydraulically set anchor below the built-in deflector for three point firm grip with the hole wall to counteract rotational tendencies.The increased reliability of the system comes from complete elimination of the cement plug and the ability to select appropriate drill bits and directional BHA for efficient kick-off and drilling a lateral. Additional benefit includes substantial cost savings in terms of reducing trip time and minimizing plugging materials.The authors will describe the system's major components and the running procedure for different drilling situations. The authors will also discuss several field runs, involving various drilling conditions and utilizing different drilling systems. The field performance along with qualifying full scale laboratory tests demonstrates the system's viability and potential for operational reliability and cost savings.