Effect of Downhole Vibration on Coiled Tubing Reach in Horizontal Intervention

Abstract

Technological advances enabled horizontal drilling to expose deeper and longer horizontal lateral sections, thereby maximizing producing zones in reservoirs. The use of Coiled Tubing (CT) to perform different types of well intervention operations is limited by the maximum depth in the horizontal section. One of the most effective remedies is the application of downhole vibration. This thesis proposes a method to describe the effect of vibrations to improve load transfer for a CT with a straight, a sinusoidally buckled and a helically buckled configuration. In order to capture the effect of vibration on the reduction of friction, the concept of apparent friction factor is introduced for all three types of section. The proposed approach is validated against published experimental data, for both the non-vibrating and the vibrating cases. Full wellbore axial force transfer and slack-off weight models are developed to simulate the effect of downhole vibration to enhance CT reach.