Design and Execution of Deepwater Jetting Operations – A Correlative Design Approach

Abstract Conductor jetting operations in deep water are vital in offshore drilling to securely install conductors and prevent subsidence. This paper details the meticulous procedures employed to ensure the successful jetting of conductors to the seabed for a deep water well in the offshore region of the Niger Delta in West Africa. With meticulous planning, considering factors such as seabed composition, water depth, and conductor specifications. There were no advanced simulation tools to aid in predicting the ideal jetting parameters, thus the methodology employed in this study relies on non-site-specific data, calibrated through information/data obtained from the Gulf of Mexico. During the operation, precise control and monitoring of jetting parameters are pivotal. Continuous monitoring of penetration depth, fluid pressure, and soil response facilitates real-time adjustments to optimize the jetting process. The application of appropriate back pressure assists in creating the requisite skin of friction, ensuring secure placement of the conductor. Post-installation assessments, which include the confirmation of conductor alignment and embedment, are conducted to verify the integrity of the installed conductor. Additionally, long-term monitoring systems are often implemented to track subsidence and ensure the stability of the conductor installation over time. This paper details the comprehensive procedures and stringent protocols integral to conductor jetting operations in deep water. The meticulous planning, precise execution, and post-installation assessments collectively contribute to ensuring the successful installation of conductors while mitigating the risks of subsidence, in challenging deep-water environments. It also confirms that with the use of the right data set and correlation, it is possible to produce an efficient design.