Abstract:The causes of the over limit deviation between the drilling tool and the center of the rotary table of the drilling tool of an offshore workover rig are analyzed. The data of platform design, construction and operation are collected, and the relevant structural deformation data of the workover rig at different well positions are checked. After strength verification and evaluation, it is confirmed that the bearing capacity of the jacket pile foundation and the strength of the upper block members still meet the requirements. The scheme of overall replacement and releveling of the deformed slide rail is put forward. After testing, it is confirmed that the proposed scheme meets the requirements of workover operation.