Trykk-aktivert drivverktøy

A running tool is disclosed to deliver tools downhole, preferably supported on a wireline. The running tool will not release the downhole tool before the desired depth is reached, even if an obstruction is encountered. The tool has the ability to release upon application of pressure in the wellbore. The tool features a floating piston with a pre-charged chamber on one side. Hydrostatic pressure acts on the opposite side of the floating piston as the running tool descends. When the downhole tool reaches its desired depth and becomes supported, slacking on the wireline traps the hydrostatic on one side of the floating piston. Applied wellbore pressure, acting on a release piston exposed to the trapped hydrostatic on its opposite side, shifts the release piston and releases the running tool from the downhole tool. On the way uphole, the trapped hydrostatic pressure is released.