Resolving Unprecedented Jack-Up Rig Leg Extraction Failures: A Case Study of Jetting System Inefficacy in Mahakam Field

Abtract The COVID-19 pandemic has significantly impacted the development of the oil and gas industry in the coming years. This global crisis has disrupted the stability of the oil and gas sector. This is increasing the demand for jack-up rigs in worldwide. However, this rising demand comes with elevated operational risks. Jack-up rigs, known as temporary offshore installations designed to operate at a single location for limited durations before relocation. Common challenges in Jack-up rig operations is difficult leg extraction prior to moving. While these issues are typically resolved using hull adjustment and jetting systems, the incident involving the Dynamo rig in the Mahakam Field proved exceptional. Despite employing a jetting system with a flow rate of 7,400 liters per minute, an adjustment hull with a total pulling load of 11,250 metric tons, and additional jetting lines around the spudcan - along with various other innovative approaches - the primary issue comes from a parted jetting line. This failure prevented proper distribution of the jetting system and severely complicated the leg extraction process. This paper documents the leg extraction process, innovative efforts undertaken to resolve this unprecedented challenge, marking a breakthrough experience never before encountered in the jack-up rig industry and world-first in offshore operations.