Coiled tubing (CT) operations using fishing services require careful design and execution because of the many variables that must be considered. Nevertheless, cost efficiency has made CT a viable option for many fishing operations compared to traditional workover options.
An intervention using a 7/32-in. logging cable was run in hole (RIH). When pulling out of hole (POOH), the wires of the cable ruptured near the logging unit blowout preventers (BOPs), leaving the entire length of the logging cable and bottomhole assembly (BHA) in the hole (17,454-ft cable and 21.3-ft BHA). Subsequently, a slickline intervention with 0.108-in. wire was performed. The tool was RIH down to 8,268 ft. During POOH, an overpull in the slickline occurred, causing a rupture and leaving wire and the BHA in the hole (2,600-ft wire and 16.8-ft BHA).
A fishing operation with 1 3/4-in.-outer diameter (OD) CT was proposed using an internal fishing spear. The well was controlled with 16.24 lbm/gal (33% solids) inverse emulsion drilling mud. A fluid change was performed to renew the heavy mud in the well to help prevent excessive drag from possible deposited solids. Subsequently, over the course of two days, a total of seven operations using internal fishing spears (two and three legged) were performed without success, retrieving only of a small portion of cable and wire. This paper describes the evolving process during this case history and the implementation of strategies, techniques, economics, and tools, which resulted in the successful fishing of the logging cable, slickline wire, and the BHA.
Solutions presented in this paper resulted in successful well intervention using fishing techniques to retrieve the lost logging cable, slickline, and BHA, enabling the operating company to continue programmed activities.