Real-Time Depth Measurement with Coiled Tubing Results in Successful Well Recompletion

Abstract

In an environment of high drilling activity and a limited amount of rigs, available alternative completion methods using Wireline or coiled tubing enables a more efficient drilling and completion process. For a successful completion, depth control is critical for the placement of perforating guns and completion hardware. Common practice is to perform the perforating using Wireline, which becomes challenging with wellbore angles over 60 deg. The use of coiled tubing enables the completion of highly deviated or horizontal wellbores, but depth critical operations performed using coiled tubing historically have presented industry challenges. Using the innovative real time depth measurement (RTDM) tool overcomes the limitations of other down hole depth-correlation methods. This paper describes the design, planning and execution of a completion in a horizontal well using coiled tubing and a RTDM tool. Introduction With high demands on the utilization of work over rigs to increase the available production levels; the improved use of resources and cost saving available by using coiled tubing to enable the execution of a sand control completion in a deviated well bore in the Gulf Coast of Mexico has lead some clients to optimize their operations with this technology. Completion Design There are a number of sand screen completions available on the market today from several service providers that can be run on coiled tubing in both mono-bore, or in through tubing1 applications. It is not within the scope of this paper to discuss the individual completion types, but more to cover the similar job design and execution principles that are required in all cases to achieve a successful operation. These principles are explored throughout this paper via a summary of a case history, however to list some main points, the following needs need to be considered as a minimum:–Rig Site Access–Available deck space and loading (crane limitations)–Personnel and equipment logistics–Simultaneous operations–Utilities and amenities–Well Bore Access and Preparation–Tubing Forces–Deployment/Well Control–Well geometry and construction–Well path–Reservoir and Completion–Production characteristics•Pressure•Volumes - solids, liquids and gases–Depth correlation–Ease of running and setting The completion design used, in the case discussed in this paper was specifically chosen for allowing the rig operation to be completed in the quickest possible time, leaving a secure well bore that could then be worked on with intervention technology to finalize the completion at the operators discretion. This allowed the required reservoir which was located in a small window of hydrocarbon bearing rock to be specifically located and produced, with the effect of any potential reservoir damage caused by the drilling process also being minimized or bypassed.