The Caspian Sea region, which includes Russia, Azerbaijan, Kazakhstan, Turkmenistan, Uzbekistan, and Iran, is one of the oldest oil-producing areas in the world and is an increasingly important source of global energy production. The area has significant oil and natural gas reserves from both offshore deposits in the Caspian Sea itself and onshore fields in the region.

Korchagin oilfield is located in the northern part of the Caspian Sea. Drilled wells are mega-reach (MD/TVD ratio greater than 3.0), with measured depths (MD) up to 23,622 ft and vertical depths of only 5,118 ft. This presents a great challenge for any well interventions, even for Coiled Tubing (CT) equipped with state-of-the-art hydraulic tractors. Limited working area, weight restrictions, challenging well geometry, completion features and lack of experience in offshore CT operations in the North Caspian Sea, required complex pre-job activities to optimize job design, select proper downhole tools and prepare a robust layout plan. This paper illustrates North Caspian project preparation challenges, on-the-job troubleshooting and workflow, supported by the well case studies and results from the first CT operation in North Caspian Offshore. Lessons learnt from the project, where all defined objectives were achieved with zero HSE (health, safety and environment) incidents, were also captured to assist in future campaigns with similar operational environment.

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