Disassembly, Re-Engineering, Mobilization and Re-Assembly Journey of the First Lift Boat from Gulf of Mexico to the Caspian Sea

Abstract

The Cheleken field offshore Turkmenistan is going through brown field development and challenges with retaining and enhancing production increase every day. Well Interventions are deemed to be a daily necessity to maintain production. Coiled Tubing, Wireline and other rigless interventions have been used directly on platforms resulting in occupying critical spaces, logistic and marine congestion (one Coiled Tubing Move comprises of over twenty lifts), structure integrity limitations, crane and lifting limitation, and a lot more. The need for a self-elevating platform arose and operator search for a proper one within the Caspian Sea ended with disappointments. This paper details the innovative and out of the box solution that was put in place to mobilize the first Lift Boat to the Caspian Sea. A lift boat was identified in the USA in the Gulf of Mexico which was underutilized after the pandemic and oil recession. The Class 230 specifications met the end user's requirements but the challenge was how to mobilize it to the Caspian. In addition, there were a handful of modifications that were requested for the Caspian operation that were not necessarily required in the Gulf. Mobilization of the lift boat must be carried out through the Volga-Don canal locking system which has a width of 57 feet 9 inch (maximum allowable beam for vessels is 56 feet 5 inches). The beam of the lift boat was 78 feet which is too wide to fit through the Volga-Don shipping canal. Hence, it was necessary to disassemble and transport the lift boat in sections. This paper describes the following: Disassembly requirements necessary to prepare the lift boat for mobilization The mobilization of the lift boat The reassembly requirements once the lift boat reached the shipyard at Caspian Sea Installation of well service and intervention equipment Technology and methodology adopted The Lift boat was disassembled into three major sections for transportation: a) the center hull module b) the port wing module, and c) the starboard wing module. The wing modules, miscellaneous equipment and containers were loaded onto a barge and sea-fastened for transportation. The center hull module was wet towed to the shipyard located in the Caspian where the lift boat was reassembled, and the well service equipment was installed. The mobilization and assembly happened during the Covid-19 era, and the vessel was hit by Hurricane Ida which impacted the disassembly schedule. Challenges on mobilizing the personnel, equipment, machinery, port clearance, etc. were all extremely tough due to Covid-19. The paper will also cover technical implications on conducting this task by complying with the classification and flag state requirements as per Turkmenistan authority. The main lesson of the paper is the identification of gaps on mobilization and how the improved techniques can be utilized for executing the task on a fast-track manner.