Patent ID: 8365826
Filing Date: 2013-02-05
Classification: E21B

Abstract:
1. A hydraulically powered fishing tool for retrieving another tool or tubular stuck in a well, comprising: a tool housing supported in a well by a work string and enclosing a plurality of axially stacked pistons generating a cumulative axial force, the tool housing including an outer sleeve, each of the plurality of pistons spaced radially between an inner tool mandrel and the outer sleeve, the outer sleeve interconnected with the work string, and each of the plurality of pistons axially movable in response to pressurized fluid transmitted downhole to the tool on the work string, the plurality of axially stacked pistons including a plurality of inner pistons each secured to the mandrel and a plurality of outer pistons each secured to the tool housing; an anchor for axially fixing the position of the tool housing in a well, the anchor movable from a run-in position to a set position; an anchor support for limiting downward movement of the anchor when the anchor is set, the anchor being releasable from the set position in response to axially upward movement of the work string; a tool mandrel axially movable upward relative to the tool housing when the anchor is set; and a fishing device on a lower end of the tool mandrel for engaging the another tool or tubular, such that axial movement of the tool mandrel in response to axial movement of the plurality of pistons dislodges the stuck another tool or tubular.