Research and Application of Key Technologies in Deep Water Developing Drilling in LS 17-2 Gas Field

LS 17-2 gas field group is the first self-developed deep-water high production gas field in the western South China Sea, with an average water depth of 1500 m. Deep-water oil and gas development not only needs to overcome harsh offshore environmental conditions, but also faces many challenges such as poor diagenesis of shallow stratum, complicated mechanical behaviors of riser and drill string, high well control requirements. So elaborate drilling technical measures have been taken including drilling rig capability evaluation, high precision underwater position system, safe avoidance distance design and directional well trajectory design, etc. Meanwhile, methods such as stability analysis of riser and subsea wellhead, checking the depth of the surface conductor into the mud, conductor installation through jetting drilling are being used as key technologies in order to complete the drilling operation safely and effciently. The successful development of LS 17-2 project further solidifies the safe and efficient operation mode of offshore deep-water drilling, and provides reference for the subsequent exploration and development of deep-water oil and gas fields.