Alaa Ahmed Dashash

Maximizing Coiled Tubing Reach during Logging Extended Horizontal Wells Using E-line Agitator

The implementation of extended reach horizontal wells in Saudi Arabia, in the southern area of the Ghawar field in particular, is being increased for production and cost optimization. Logging these wells is a challenge, as the production profile of a horizontal section cannot be entirely recorded with conventional coiled tubing (CT). This is mainly because of friction forces between the CT and the wellbore, which cause the CT to lockup significantly shallower than the total depth (TD). Even with the availability of a limited technique, such as a metal to metal friction reducer, it was found that the CT reach cannot be maximized effectively. This article will describe successful utilization of an agitator tool with a custom designed e-line bypass that helps the CT maximize the coverage of the horizontal section for logging purposes. The agitator tool was incorporated into the Production Logging Tool (PLT) and bottom-hole assembly (BHA). It was activated by pumping. It caused the CT string to vibrate and subsequently reduce the friction contact between the CT and the wellbore to allow the CT to run beyond the normal lockup depth. The tool was trial tested in an extended reach horizontal well, with a TD of 12,118 ft. The simulator showed a predicted lock at 10,400 ft while a dummy run locked up at 10,800 ft without activating the agitator. The e-line agitator was activated while the well was flowing at a restricted rate, which maximized the reach to the TD and reduced the friction coefficient by around 26%. Different conditions and parameters were applied to understand the best performance of the e-line agitator tool. The implementation of the e-line agitator resulted in extending the reach of the CT by an additional 1,300 ft and reaching TD. This additional reach was significant, as the last part of the horizontal section was contributing water. The production log has been reviewed and shows acceptable measurements. This article will cover the whole cycle of candidate selection, job design, execution, post job evaluation, lessons learned and conclusion.