Instrumented High-Force Wireline Fishing Tool

Abstract

This paper outlines the capabilities and advantages of a 3 1/8-in. instrumented wireline tool designed for fishing or shifting in casedhole wells with up to 90,000 lbf with high precision and minimized tubular deformation. Some fishing necks have ratings higher than maximum capacity for linear actuators of similar size. To maximize the pull force applied to the fish, it was necessary to intervene with a linear actuator with a capacity at least as high as the fishing neck, but without increasing diameter to the point that it did not fit in the tubing or through restrictions above the fish. It is additionally necessary to accomplish this high pull without damage to the tubular where the linear actuator reacts the force applied to the fish. This imposes a requirement on the anchor module to avoid applying excessive radial forces to the inside of the tubular. A linear actuator was designed that has proven a pull capacity of up to 90,000 lbf to fish stuck tools without exceeding a 3 1/8-in. tool diameter. This module can achieve this feat with precision measurements on the force applied to the fish, the displacement of the fish relative to the tubular, the radial force applied to the tubular by the anchors, and the exact opening position of the anchors. It also carries onboard temperature and pressure measurements to detect changes in wellbore parameters when used for exercising stuck ball valves or sliding sleeves. Extensive simulations have been completed to aid in operational planning and ensure anchor pads do not damage the wall of the tubulars. Multiple anchor modules can be run in series to further distribute radial and axial loads if needed for thin-walled tubing. The use of high-precision instrumentation and high-strength mechanical design enabled a linear actuator to accurately pull twice as much as similar linear actuators with the same physical dimensions. This allows wireline to complete fishing operations in casedhole wells that were previously inaccessible either because of force requirements or diameter constraints, surpassing coiled tubing capacity.