Coiled Tubing Buckling Implication in Drilling and Completing Horizontal Wells

Abstract This paper discusses coiled tubing buckling and load transmission when drilling and completing horizontal wells. Comprehensive analyses and new equations are presented to predict buckling of coiled tubing, "slack-off" weight transmission, actual bit weight or packer load, and maximum horizontal length. Coiled tubing "lockup" and yield due to buckling are also discussed. These equations can also be used for other coiled tubing operations, such as coiled tubing workover, coiled tubing well stimulation, and even for conventional joint-connected drill strings. Calculations based on the equations presented are also compared with the previous literature.