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Cementing through coiled tubing electric line (CT e-line) is not a common practice; this application is highly recommended in Coiled Tubing Drilling (CTD) applications using the existing CT e-line pipe to achieve a better time performance for sidetracking a well since using the CTD technique is mainly based on economical evaluation. Several considerations need to be taken into account while designing the job and performing the operation. The relatively high density and viscosity fluid can lead to bird nesting the cable due to high friction and excessive slack inside the pipe; it can also affect the integrity of the cable as well as the performance of the bottomhole assembly (BHA). The interface between cement and other fluids pumped through CT e-line pipe can be also affected. A review on a feasibility study of cementing through CT e-line that was performed in 2003 in Alaska highlights all the concerns, challenges, and potential issues that can be encountered during a cementing job through CT e-line, best practices, lessons learned, and way forward to implement this technique. This review is supported by two successful case histories performed in Malaysia CTD campaign applying this technique for different objectives: remedial cementing for casing and tubing sealing in a deviated well and remedial cement plug for window recovery. By implementing cementing through CT e-line, the effective job time was improved by avoiding swapping pipes in an offshore environment where the logistic, safety, and space accommodation is a huge challenge. The use of CTD as an economical sidetracking technology was reinforced by making the CT e-line pipe universally utilized in all the project steps, even for running and setting completion. |
