Treatment practice of sloughing and sticking in offshore deep wells with complex trajectories

A majority of adjustment wells drilled in eastern parts of South China Sea are characterized by big depth and complex borehole trajectory. In case of sticking incidents, forces for stuck releasing may not be transferred effectively, consequently, stuck releasing operations in these wells may involve huge difficulties. By analyzing root causes of sticking incidents in Well A in the offshore Lufeng 13-1 Oilfield in the paleogene enping formation, techniques such as stuck releasing through circulation and gradual lifting with minor discharging volumes have been developed to release stuck drilling tools effectively. These newly developed technologies may serve as fast and highly effective ways to remove problems related to sloughing and sticking in the area. In addition, these techniques may provide necessary guidance for dealing with sloughing and sticking problems in wells with similar conditions.