Back to results
US 4,790,384 AGranted
Hydraulic well penetration apparatus and method
AssigneePenetrators, Inc.
InventorsHerman J. Schellstede, Robert W. McQueen, Alan D. Peters
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneePenetrators, Inc.
InventorsHerman J. Schellstede, Robert W. McQueen, Alan D. Peters
Estimating the term…
A well casing penetrator includes an elongated housing enclosing an outwardly movable hydraulic cylinder driven punch for cutting an opening in a casing. A high pressure liquid jet nozzle is mounted on the end of a hose which moves outwardly through an axial bore in the punch when extended through the casing to cut a radially extending opening in the surrounding earth. The punch includes arcuately curved longitudinal slots along opposite sides which cause tabs to be bent back along opposite sides of the opening cut in the casing to prevent dislodging of any portion of the casing from the casing as a consequence of the operation of the punch. A spool piston is connected to a single accumulator that is pressurized to urge the spool piston toward a first position in which work fluid controlled by the spool piston retracts the hydraulic punch cylinder and a hose drive cylinder for moving the hose in the punch. When the pressure is increased the accumulator is overcome and the punch cylinder and the hose drive cylinder are activated along with apparatus supplying work fluid to the hose to initiate a penetration operation. The parts return to their original retracted position upon lowering of the work pressure.
In a well penetrator of the type including a housing means, a working fluid input means in said housing means, an outwardly movable punch member having an inner end and an outer end, said outer end including casing cutting means for cutting an opening in a casing when moved forcefully against such casing, means supporting said punch member for movement relative to said housing means between a retracted position in which said outer end of said punch member is positioned substantially within the confines of said housing means and an extended position in which said outer end of said punch member is positioned outwardly of said housing means, power actuated punch drive means mounted in said housing means for moving said punch member between its retracted and extended positions, high pressure lance means having nozzle means mounted on one end for movement in said punch member between a retracted position in which said nozzle means is positioned internally of said punch member and an extended position in which said nozzle means is positioned externally of said punch member for discharging a high pressure jet outwardly beyond the outer end of said punch member for cutting and removing the surrounding earth formation, nozzle positioning drive means mounted in said housing means for moving said nozzle toward its extended position and for retracting said nozzle toward its retracted position, the improvement comprising control means mounted in said housing means responsive to the input of working fluid at a pressure above a predetermined pressure for substantially simultaneously actuating said punch drive means and said nozzle positioning drive means to effect substantially simultaneously the initiation of movement of said punch means and said nozzle means from their retracted positions toward their extended positions.
A method of penetrating a well casing and surrounding earth strata comprising the steps of:
A well penetrator of the type including a housing means, a source of pressurized working fluid provided in said housing means, selectively operable control means connected to said source of pressurized working fluid, an outwardly movable punch member having an inner end and an outer end and being mounted for axial movement between a retracted position in which said punch member is fully enclosed within said housing means and an extended position in which the outer end of said punch member extends outwardly of said housing means a sufficient distance to cut through a well casing in which the housing means is positioned, wedge cam means mounted in said housing means for reciprocation, camming surface means on said wedge cam means, cam follower means engaging said camming surface means and connected to said punch member so that axial movement of said wedge cam means extends or retracts said punch member relative to said housing means, hydraulic cylinder means, a piston and rod assembly mounted for movement in said hydraulic cylinder means, means connecting said piston and rod assembly to said wedge cam means and wherein said wedge cam means is mounted between said hydraulic cylinder and said source of pressurized working fluid and further including conduit means fixedly connected on an upper end to said control means and having a lower fixedly positioned conduit portion extending axially through said wedge cam means so that said wedge cam means is moveable relative to said lower fixedly positioned conduit portion which is connected in communication with said hydraulic cylinder means and wherein said control means includes means for connecting said source of pressurized working fluid to said conduit means or for alternatively connecting said conduit means to exhaust for effecting movement of said piston and rod assembly and said wedge cam means.
In a well penetrator for penetrating the casing of a well of the type including a housing means, high pressure lance means having an inner end and an outer end and nozzle means on said outer end, said lance means being mounted for movement outwardly of the housing means through the casing of a well for penetrating the surrounding formation by the ejection of a high pressure jet from nozzle means on the outer end of the lance means, the improvement comprising power means mounted in said housing means for extending the lance means from the casing and retracting the lance means into the casing, said power means comprising first and second cylinder means mounted in the housing means, first and second piston means respectively mounted for reciprocation in said first and second cylinder means, rod means connecting said first and second piston means to each other and to the inner end of said lance means, sealing means engaging said rod means for hydraulically isolating said first and second cylinder means, selectively operable power fluid supply means in said housing means for selectively simultaneously supplying pressurized fluid to said first and second cylinder means at locations between said first and second piston means on opposite sides of said sealing means for selectively extending and retracting said lance means while simultaneously maintaining tension in said rod means.
Dependencies are inferred from the claim text.