Key Technologies for Drilling Design of Deep Well Take-1

The design depth of Well Take-1 is 11100 meters, with a predicted bottom hole temperature of 213 °C and a predicted formation pressure of 133 MPa. The drilling operation encounters exceptionally severe well conditions characterized by ultra deep, ultra-high temperature, ultra-high pressure, and high sulfur content. By conducting geological engineering, integration research, the distribution patterns of fractures in igneous rocks, gypsum salt rocks, and carbonate rocks and the engineering risks they bring were determined. The well positions were optimized to reduce the engineering difficulty while fulfilling geological objectives. Building upon comprehensive research in geological engineering intergration and prediction of five pressure profiles, this study meticulously considered the deep geological and engineering risks, and designed the five-section casing program. The design and verification of ultra-deep well casings were carried out. The tensile strength of the casing and the bearing capacity of the drilling rig were taken into consideration, and the force of wellhead tools on the ultra-long and overweight casing was simulated and calculated to avoid plastic deformation of the casing during the operation. Moreover, the design of the drilling tool assembly fully considered hydraulic parameters and vibration effects. This approach ensured safe drilling practices and facilitated speed enhancements within the the optimal drilling parameter range. On-site implementation progress demonstrates that the key technologies in drilling design for Well Take-1 can solve the drilling technical difficulties and achieve the goal of successful ultra-deep drilling at a depth of 10000meters.