Abstract: The present invention relates to a hammer device, preferably a down-the-hole hammer, including a drill bit (11) and a piston (10) reciprocating therebehind to periodically strike the drill bit. The drill bit (11) includes front (11a) and rear (11b) portions of different impedance, and the piston (10) includes front (10b) and rear (10a) portions of different impedance. In the drill bit, the front portion (11a) has a larger impedance than the rear portion (11b). In the piston, the rear portion (10a) has a larger impedance than the front portion (10b). The length of the drill bit front portion (11a) is about twice the length of the drill bit rear portion (11b). The length of the piston rear portion (10a) is about twice the length of the piston front portion (11b). The invention further relates to a drill bit (11) and a piston (10), per se.

Abstract: A dual acting hydraulic jarring enhancer which is particularly well suited for coiled tubing application. A common annular chamber is formed between reciprocating cylindrical assemblies, and a piston is positioned within the annular chamber. The inner cylindrical assembly has a member to contact the piston and move it relative to the outer cylindrical assembly in one direction while the outer cylindrical assembly has a member to prohibit longitudinal movement of the piston relative to the inner cylindrical assembly in a second direction. In this manner, the present invention provides a tool with overall minimal length by using a singular annular chamber capable of being divided into two other chambers and providing an accelerating effect to a hammer/anvil of an associated jarring tool in either an upjarring or downjarring mode.

Abstract: An apparatus for securing a soil testing device and other attachments necessary for soil testing near the bottom of a borehole uses a pair of clamps with gripping teeth that interlock with similar gripping teeth in the internal wall of the auger. The lateral movements of the clamps toward the auger are controlled so that the soil testing device is maintained in a proper orientation with respect to the soil sample and to avoid uncontrolled engagements of the clamps with the auger.

Abstract: A rolling cutter drill bit comprises a main body and three depending legs, each leg having a cantilevered bearing spindle on which a rolling cutter is rotatably mounted. Bearings located between the cutter and spindle include a radial bearing, and a thrust bearing configured to carry onward thrust loads from the cutter onto the spindle. A bearing seal defines an enclosed region between the cutter and the spindle in which the bearings are located, and a pressure balanced lubricant delivery system within the spindle delivers lubricant to the bearings. The lubricant delivery system includes a non-return valve to allow lubricant to flow into the area of the enclosed region containing the thrust bearing and the area is bounded by a tortuous flow path which allows a more restricted flow of lubricant out of the thrust bearing area and into another area of the enclosed region, without pressurizing the bearing seal.

Abstract: An apparatus for joining one pipe section that contains a pressurized fluid, such as a pipe section formed from a non-metallic material in the sensing section of a drill string, to another pipe section so as to minimize the pressure gradient acting across the joint. An inner sleeve is installed within the pipe section so as to extend across the joint, thereby forming an annular chamber between the inner sleeve and the joint. Seals at the ends of the inner sleeve prevent the fluid flowing within the pipe section from flowing into the annular chamber. A vent hole allows fluid flowing outside the pipe section to enter the annular chamber and pressurize it to the same pressure as the fluid, thereby equalizing the pressure across the joint. Alternatively, the annular chamber can be filled with an incompressible fluid and a pressure balancing piston used to equalize the internal and external pressures acting on the joint.

Abstract: A casing annulus remediation system for overcoming problems associated with lowering a flexible hose into an annulus between strings of casing in a petroleum well by pressurizing the hose so that the hose is rigid and may be forced down the annulus. It is necessary to insert the hose through an outlet into the annulus region for brine displacement when pressure builds up in the annulus between casing strings due to leaks in the casing. Pressure build-up in the annulus is reduced by pumping a heavy liquid through the hose into the annular space experiencing the pressure build-up. A nozzle is affixed to the lower end of the hose. The hose may be inserted several hundred feet into the well. Therefore, the hose is pressurized to maintain rigidity to keep the hose from winding about the well during deployment. To keep the hose rigid, internal pressure is maintained in the hose. The nozzle is provided with a burst disk that holds the pressure.

Abstract: Steel bit bodies are manufactured with polystyrene patterns in a lost foam casting process. The patterns are machined in complex shapes that cannot be extracted from reusable, two-piece pattern molds. The patterns are machined in a basic, programmed, five-axis machining process to form multiple copies of a complex pattern body. The process is modified to produce multiple copies of a modified design. Multiple bit patterns of variable forms are produced without an intermediate, reusable pattern mold that requires multiple mold pieces, thus eliminating the time and expense in variation of the bit design. The pattern is machined in a single chucking operation in a machine tool adapted for machining plastics in a three-dimensional global process. The plastic composition and density permit it to be machined into a pattern having relatively small, unsupported structural projections and smooth surface features.

Abstract: A method of severing a downhole pipe for forming a region in the well borehole devoid of downhole pipe for enhancing the performance of a perforating gun comprising the steps of: severing, at an angle, by a first cutting tool the downhole pipe to form an upper downhole pipe portion and a lower downhole pipe portion to form a sloped cut line; releasing potential energy stored in the upper downhole pipe portion and the lower downhole pipe portion; inserting a plug to seal an up-hole portion of the upper downhole pipe portion; cutting the up-hole portion via a second cutting tool above the plug into an upper piece and a lower piece; and, jettisoning the lower piece downwardly wherein as the lower piece jettisons downwardly the region in the well borehole devoid of downhole pipe is formed. Such method eliminates the need for: removing a well head; a crane or rig for raising a cut up-hole pipe; and, a pump for controlling the pressure of the well.

Abstract: An apparatus for obtaining subterranean soil samples includes an elongated housing having a passageway extending longitudinally therethrough, a tip assembly movable through the passageway, and a locking device for releasably preventing the tip assembly from moving from a first portion of the passageway to a second portion of the passageway. The sampling method includes the steps of inserting the sampling apparatus into the ground, unlocking the tip assembly, pulling the tip assembly through the passageway and retaining the tip assembly in the second portion of the passageway. A device is provided for creating a vacuum pressure above the sample material as the tip assembly is retracted and for retaining the sample material in a sample chamber.

Abstract: A well testing system is described which comprises a ball valve (10) having a plurality of fluid lines coupled thereto (20a, 20b, 20 c). The ball valve (10) is located between a process fluid flow line (16) and a vent line (18) with each fluid line (20a, 20b, 20c) being coupled to a respective piece of well-test equipment rated at a certain pressure value. Pressure relief means (22a, 22b, 22c) are located in each fluid line (20a, 20b, 22c) between the piece of equipment and said valve (10) and each pressure relief means (22a, 22b, 22c) is operable when the in-line fluid pressure exceeds a predetermined value to pass said fluid to said ball valve(10).

Abstract: An accelerator having a tubular housing and a tubular mandrel substantially coaxial arranged for telescoping longitudinal movement within the tubular housing, the accelerator also including: a first piston positioned radially between the tubular housing and mandrel, the first piston being adapted for movement with the mandrel in response to movement of the mandrel in a first longitudinal direction relative to the housing and adapted to resist longitudinal movement in response to movement of the mandrel in a second longitudinal direction relative to the housing; and a second piston positioned radially between the tubular housing and mandrel, the first and second pistons forming a substantially sealed gas chamber therebetween, the second piston being adapted for movement with the mandrel in the second longitudinal direction relative to the housing and adapted to resist longitudinal movement in response to movement of the mandrel in the first longitudinal direction relative to the housing, and whereby the chambe

Abstract: An auger bit for boring ski post holes having an elongated shank with a drill head fixed at a first end of the shank. The preferred drill head has diametrically opposed first and second open chip mouths, each defined by an advancing face and a trailing face of the drill head. The advancing face of the drill head may be oriented at a vertical rake angle and at a radial advance angle for propelling debris proximally from the drill head into and through the first and second chip mouths into first and second chip throats. The bit may include first and second excavating helices wound around the shank for a given number of rotations each at a given helix angle whereby first and second chip throats are formed. The second excavating helix may wind around the shank for a lesser number of rotations than does the first whereby a unitary chip throat succeeds the first and second chip throats. Preferably, the bit has an overall length greater than about fifteen inches and a shank which is hollow.

Abstract: A novel apparatus and method for producing oil and natural gas from an oil well in the later stages of the well's lifetime. The apparatus includes a one-way valve located at the bottom of the conventional production tubing and a string of macaroni tubing inserted inside of the production tubing. The three chambers defined by the casing, the production tubing, and the macaroni tubing, are connectable to either the suction or discharge manifolds of the apparatus, which are in turn connectable to a compressor. With the valves manipulated in the appropriate fashion by the controller, pressure differentials can be created in the down-hole region of the well to force oil first into the macaroni tubing and then force it up and out of the macaroni tubing and to the sales line. An optional plunger may be used to help reduce paraffin or scale buildup in the macaroni tubing.

Abstract: An erosion resistant downhole diverter tool (210) comprises a generally cylindrical body (212) which may be configured as a slick sub or may include stabilizing blades (260). Located within the body 212 are a plurality of erosion-resistant, removable, cylindrical inserts (220). Each insert has an aperture (222) formed therein, aligned with a corresponding aperture (218) formed in the cylindrical body (212). Located within the apertures (218) in the cylindrical body (212) are pressure responsive, normally-closed valve assemblies (300), incorporating jet nozzles, which open in response to increased fluid pressure within the tool to provide fluid jets directed into the annulus surrounding the tool in a borehole or the like. The upper ends of the stabilizer blades (260) may include cutting structures to provide a back-reaming function.

Abstract: A fluid loss device has a housing, a seal assembly, a running tool, and a plug. The housing of the fluid loss device is placed in a production string before a well bore is completed. The plug is attached to the running tool, and the running tool is attached to a wash pipe.The fluid loss device is activated by lifting the wash pipe and the running tool, thereby engaging the plug with the seal assembly, engaging the seal assembly with the housing, and severing the plug from the running tool. Activation of the fluid loss device inhibits fluid communication through the fluid loss device and reduces damage to the well structure behind the fluid loss device while completion operations are performed in other areas of the well bore.The fluid loss device is deactivated by forcing the plug through the fluid loss device with mechanical force or pressure, or by chemically eroding the diameter of the plug until the plug passes through the fluid loss device.

Abstract: A damage-resistant filter for use in subterranean wells has at least one layer of a filter medium, such as a sintered supported porous membrane, coaxially disposed about a perforated support member. The filter may also include a drainage layer disposed between the inner support member and the filter medium, and a protective covering, such as a perforated cage, surrounding the filter medium. The filter is particularly suitable for removal of sand and other particulates from fluids produced in a well.

Abstract: A cutting insert for a tool for wellbore milling operations has been invented that has a body having a top, a bottom, and a base, and a plurality of cutting surfaces on the top of the body, one of the cutting surfaces at a different height above the base than the other cutting surface, each cutting surface defined by linear boundaries extending from a first edge of the cutting insert, and the linear boundaries parallel to each other, the plurality of cutting surfaces including at least two cutting surfaces including at least a first cutting surface and a second cutting surface, the second cutting surface at a height above the base which is greater than a height above the base of the first cutting surface.

Abstract: A deformable well screen for preventing migration of solid particles into a hydrocarbon production well is disclosed, the screen including at least one substantially tubular filter layer of which the sieve opening size remains fairly constant during or after expansion and/or other formation of the screen. Optionally the screen also includes a series of circumferentially scaled filter segments that are arranged around an expandable slotted tube, an expandable slotted tube of which the slots are filled with resin coated granules, an expandable slotted tube with micro-slots, an assembly of woven metal wire screens that are sintered together and/or a synthetic geotextile fabric.

Abstract: The invention is a process and method for determination of the depth of a well during the process of drilling. A computer is housed in the drilling tool and pre-programmed with the data of the planned pattern of the borehole. Changes in the drilling mud pressure or flow of the drilling mud are detected by a downhole sensor and are used as a counter for the number of drilling string segments used. This, together with the known length of a drilling string segment, enables the computer to calculate the depth of the tool. The calculated depth is used by the computer to control the direction controlling device of the drilling tool.

Abstract: According to the present invention, there is provided a device for guiding a tool on a string within a blow out prevention ("BOP") stack. In one embodiment, the device includes a top collar connected to a bottom collar by a shroud having a plurality of flexible members which bow outwardly from the collars, wherein the shroud covers a portion of the tool. An energy absorbing bumper is provided above the top collar to absorb structural impact caused by a blow out or other inadvertant pressure in a downhole application.