Abstract: A system for cleaning perforations in a well bore where the perforations are located below a packer means on a production tubing. A tool on a string of pipe has packer means for sealing off the cross-section of the production tubing and the pressure in the annulus between the string of pipe and production tubing is reduced. The tool has a bypass passage across the packer means which opens upon the reaching of a predetermined pressure across the packer means and the high volume pressure from the earth formations suddenly flows through the tool and cleaning of the perforations is effected.

Abstract: A formation tester apparatus for use in a well bore for multiple testing of pressures of earth formation fluids and the taking of a fluid sample, including pad and shoe elements selectively operable for sealingly engaging a well bore. Upon sealing engagement of the pad element with the wall of a well bore, a fluid sample is ingested into an expanding chamber while its pressure is sensed. Upon completion of the pressure test, the pad element is retracted from the wall of a well bore, and the expanding chamber contracts to expel the fluid sample. The pressure test may be repeated any number of times. The expanding chamber includes a piston operated with fluid pressure used to actuate the pad element. A choke delays the application of pressure to the piston until after the pad element seals on the wall of the well bore.

Abstract: A system for effecting a fluid tight seal between two surfaces where one of the surfaces has an annular recess for receiving an annular sealing element which typically is an elastomeric sealing element. The sealing element is compressed when disposed between the surfaces to be sealed and a supplemental sealing element is disposed in the groove between the sealing element where the supplemental sealing element is comprised of a semi-fluid bridging material containing particulate matter. The particulate matter is sized so as to be larger than a clearance space between the surfaces thereby providing material to bridge the clearance space and prevent the extrusion of the principal sealing element in the event of high pressure.

Abstract: A tool sized for lowering through a tubing string disposed in a well bore by means of a wire line and activated upon exiting from the tubing string for setting a pack-off means to close off the cross-section of the tubing string. The wire line is releasable from the tool so that fluid can be removed from the tubing bore thereby producing a pressure differential across the tool. A sinker bar from the surface is dropped through the tubing string and, upon contact with the tool, actuates the tool to release the pressure differential so that the formations below the tubing string may suddenly produce fluid and thereby be cleaned. At the time of release of the pressure differential, the pack-off means is released so that the tool can subsequently drop from the end of the tubing leaving the tubing bore unrestricted.

Abstract: A cased borehole has a tubing string run downhole thereof. A packer affixed to the tubing is set with the tubing string terminating in proximity of a hydrocarbon producing formation to be completed. A wireline operated perforating gun is suspended from a mass by means of a lost motion coupling and the mass is suspended from a wireline. The entire apparatus is run downhole and positioned adjacent to the hydrocarbon containing formation. The gun is detonated; whereupon formation fluid enters the casing and tends to thrust the gun uphole respective to the mass and to the wireline. The relative motion between the gun and mass is advantageously used to set a tool hold down apparatus which arrests uphole thrust of the gun. The gun can be subsequently retrieved by lifting the mass with the wireline, thereby releasing the tool hold down apparatus and enabling wireline retrieval of the entire apparatus suspended from the wireline.

Abstract: Method of completing a hydrocarbon containing formation located downhole in a cased borehole by running a jet perforating gun downhole on the end of a tubing string. The tool string includes a vent assembly underlying a packer and located above the gun. The gun includes a special flexible linkage and biasing means which urges the shaped charge chambers of the gun into close proximity of the borehole wall. Pairs of shaped charges are positioned within spaced chambers to intersect one another out in the formation, to thereby enable a cavity to be subsequently formed therebetween. Treatment fluid is pumped into the cavity and used to consolidate the formation. Another form of the invention provides a wireline actuated apparatus wherein pairs of shaped charges are oriented to penetrate the formation and form spaced apart parallel tunnels which subsequently collapse to jointly form an enlarged cavity located back up in the formation.

Abstract: In the representative embodiment of the new and improved formation-testing apparatus disclosed herein, a wall-engaging sealing pad is arranged around the forward end of a normally open tubular probe which is adapted to be placed in communication with an adjacent earth formation and carries an extendible filter probe coaxially supported therein by a tubular valve member. If a formation being tested is relatively incompetent, the filter probe will be advanced into the formation without allowing further erosion of loose formation materials with the valve member acting to block communication through the outer probe. Alternatively, should a formation being tested be relatively competent, the filter probe will remain in its normal retracted position and the valve member will cooperatively block communication through the filter probe and instead provide an unrestricted flow passage through the outer probe to a sample-collecting system on the apparatus.