Abstract: A pressure-boosting apparatus particularly amenable for use in downhole applications is disclosed. The pressure-boosting apparatus employs an unbalanced piston which is initially fixated in a run-in position. The piston has a flowpath therethrough in which is mounted a check valve. Initially, pressure is applied to above and below the piston which results in an unbalanced force on the piston due to its configuration. Flow to the tool initiates its actuation at this time. When the unbalanced force reaches a predetermined level, the piston is no longer fixated to the housing and begins to accelerate. Acceleration of the piston closes the check valve due to the sudden decrease in pressure behind the check valve and an increase in pressure in front of the check valve as the fluid volume in front of the piston is compressed.

Abstract: A proppant containment apparatus and associated method of using the apparatus permit continued delivery of a proppant slurry to a subterranean wellbore after failure of a crossover portion of the apparatus during a fracturing operation, eliminating the need to stop the fracturing operation and remove and replace expensive items of equipment after such crossover failure. In a preferred embodiment, the proppant containment apparatus has a tubular crossover member with an internal flow passage, circulation port, and side wall outlet openings, first and second coaxial tubular structures, the first tubular structure being perforated, a tubular screen positioned between the first and second tubular structures, a ball, and a ball seat having a spaced series of grooves formed thereon.

Abstract: A hydraulically or pneumatically releasable disconnecting device (1), through which a liquid can flow, and wherein two end pieces (2, 3) are connected in that an expandable locking ring (20) in normal position engages grooves (23) in a locking sleeve (10). An axially displaceable locking sleeve (6) surrounds the locking ring (20) with one end thereof and prevents the locking ring (20) from expanding and disengage the grooves (23). The locking sleeve (6) is fixed with shear pins (7). When the disconnecting device (1) is to be released, a sealing body (14) is placed in a seat (13) in a piston sleeve (12), preventing flow of liquid therethrough. Hydraulic force acting against the sealing body (14) and the piston sleeve (12), urges the piston sleeve (12) against the safety sleeve (6) such that the shear pins (7) are broken. Thus, the safety sleeve (6) is displaced such that it can no longer surround the locking ring (20).

Abstract: An apparatus and method for controlling a well plunger system for the production of natural gas is described. The well plunger system includes a plunger tube positioned within a casing of a gas well, a tubing line connected to the plunger tube, a plunger moveable within the plunger tube, a plunger sensor for detecting the presence of the plunger, a valve connected to the tubing line and to the general gas distribution system including a sales line and a gas flow meter, a pressure sensor connected to the sales line, a motor for operating the valve, and a pressure sensor connected to the casing. The controller calculates the duration of an open interval when the valve is opened and a closed interval when the valve is closed based on a calculated average plunger velocity of the plunger after the valve is opened. The controller compensates for changes in sales line pressure by adjusting the calculated average plunger velocity by an amount equivalent to the changes in sales line pressure.

Abstract: A borehole drilling apparatus has a jacket attachable to a well head and through which a drill rod passes and which carries pressurized drilling fluid to a working end of the drill rod and out into an annulus of the borehole. The jacket has a drill rod seal and an outlet port leading from the interior of the jacket to a pressure regulator. The pressure regulator comprises an annular space through which fluid can flow from an inlet to an outlet. The annular space is defined between an inner rod and a surrounding elastomer pipe. In use, the elastomer pipe is squeezed radially inwards toward the inner rod by fluid pressure maintained between the outside of the elastomer pipe and a surrounding housing. A sampling system is in communication with the outlet port at a location upstream of the regulator.

Abstract: A high density perforating gun having a carrier housing tube and an interior charge holder tube through which are mounted zinc alloy shaped charges in a phased relationship between about 135 and 145 degrees. The 135 to 145 degree phased relationship provides for an 18 shot per foot perforating gun system. The shaped charges of selected length are inserted into the carrier housing tube and held in place by fastener rings fitted to fastener ring slots. The nose ends of the shaped charges are fitted with ears to receive a detonating cord. This positions the primer cord in tension and generally coaxially with the carrier housing tube to prevent charge interference and assure sequential detonation.

Abstract: Methods and apparatus are provided for draining or removing well fluid from a production tubing string into a well borehole while pulling the tubing string from the well. A special length of tubing is provided near the lower end of the tubing string with a drain port communicating the interior and exterior of the tubing. The drain port is initially plugged and sealed with a knock out plug. When it is desired to remove the tubing string from the well and drain its fluid into the borehole, a drop sleeve is dropped from the surface to shear and open the knock out plug. A sleeve stop catches the drop sleeve for re-use.

Abstract: An inflatable packer includes a packer mandrel and an inflatable element reinforced across its entire length and attached at each end to the packer mandrel. The inflatable element is formed of multiple layers of elastomeric material including reinforcing plies of an elastomeric base material reinforced with helically wound strands of a reinforcing material. The reinforcing strands are evenly spaced and parallel to one another and are oriented at a predetermined helical angle with respect to a longitudinal axis of the packer. The helical angle and modulus of elasticity of the reinforcing strands can be selected to allow the inflatable element to expand by a predetermined amount even though its ends are fixed.

Abstract: Arrangement in a hydraulically operated rock drilling equipment comprising a feed motor (3), a percussion device (2), and a hydraulic pump (1) for feeding hydraulic fluid to the feed motor (3) and the percussion device (2). The arrangement comprises a pressure control valve (17) connected to be controlled on the basis of the control signal of the feed regulation valve (8) when starting the drilling so that when the value of the control signal is below a predetermined switching value, the pressure relief valve (18) is connected to the percussion pressure line (13) of the percussion device (2), and when the control signal exceeds the switching value, the pressure control valve (17) disconnects the pressure relief valve (18) from the percussion pressure line (13) and connects the pressure difference valve (20) in communication with the percussion pressure line (13).

Abstract: A drilling assembly for drilling holes in subsurface formations comprises a drill bit 10, a drive unit 12 including a housing and a rotor 11 operatively coupled to the drill bit to rotate the drill bit relative to the housing, and a modulated bias unit 14 coupled to rotate with the drive unit housing and apply a lateral bias thereto in synchronism with rotation of the housing. The modulated bias unit 14 comprises one or more hydraulic actuators including members 16 which, in use, bear against the sides of the borehole, and means for modulating the pressure of fluid supplied to the actuators in synchronism with rotation of a component of the drilling assembly, and in selected angular phase relation thereto, whereby each hydraulic actuator is actuated in a selected rotational position of the component.

Abstract: A directional boring apparatus is disclosed where the apparatus is controlled through a method which includes deviating a drill head from a straight path into a desired direction angled away from the straight path. The deviation is achieved by applying an axial force to the drill head when a drill head cutting member is positioned within an arc of rotation through which the desired direction passes. The drill head is retracted when the cutting member is outside of the arc of rotation.

Abstract: A subsea wellhead tieback connector operatively used to connect to a marine riser pipe or a well conductor in a manner that that will not unthread or unloosen the joints of the riser pipe being unlocked. The tieback connector operates with a novel internal latching mechanism having a hydraulic piston, an inner body that stretches and deflects in a unique manner resulting in compression spring forces at two locations, an expanding lock ring, a threaded adjustment ring, and a reaction ring. During operation the tieback connector creates an enhanced mechanical advantage to originate a required pre-load force without the necessity of having to generate a large hydraulic force that would otherwise be needed.

Abstract: An improved coiled tubing pulling tool and methods of using the pulling tool for pulling a well tool from a well bore, relocating a well tool in the well bore and performing other similar operations.

Abstract: A rotary drill bit (10) has a jet pump device including a plurality of jet pump assemblies (26). Each jet pump assembly (26) has an outer housing (28) secured to the bit body (14) and receiving any elongate nozzle member (46) therein in concentric relation to form an annular chamber (48) therein. A flow restriction (38) is mounted within the outer housing (28) above the nozzle member (46). The elongate nozzle member (46) has a lower nozzle port (50) and an opposed upper nozzle port (52). Drilling fluid from the central bore (20) is directed to the nozzle member (46) where the drilling fluid is divided into two streams, one stream for flow through lower nozzle port (50) against the formation and the outer stream for flow through the upper nozzle port (52) and flow restriction (38) to create a low pressure area or suction in an annular chamber (48). A low pressure cross sectional area is formed at the bottom of the bore hole (B, FIG.

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 pier and beam bridge structure is formed essentially entirely from steel reinforced, precast concrete elements including elongated, hollow tubular pier members, pier collars, pier base and cap beams, deck beams, deck slabs and side railing members. In forming the support pier structures, the pier members are inserted into dry-drilled pier base excavations through opposite end openings formed in the ground-supported base beams, and are outwardly circumscribed by the collars which are received at their opposite ends in the base beam end openings and openings in the cap beams which are supported at the upper pier ends. A loose aggregate material is dumped into the pier member interiors, and the annular collar and excavation spaces surrounding the pier members. Polymer concrete is then forced downwardly through the pier member interiors, and upwardly through these annular spaces, and cures in a matter of minutes to complete the fabrication of each pier structure.

Abstract: A tubing tightener which is readily adaptable to either clockwise or anti-clockwise rotational setting operation and which uses a series of drag slips having integral drag and slip surface regions. The drag surface regions are substantially smooth and are advanced into contact with a wellbore with the slip surface regions retracted, when the tightener is in its unlocked orientation. The slip surface regions are serrated to provide a positive engagement with the wellbore and are advanced into engagement with the wellbore with the drag surface regions retracted, when the tightener is in its locked orientation. The drag slips are caused to rock about a point of contact between the drag slip surfaces and the wellbore, located intermediate the drag and slip surface regions, in order to advance the appropriate surface region of each drag slip into engagement with the wellbore. The invention provides for a compact, lightweight construction with improved reliability and increased bypass around the tightener.

Abstract: Various rock spallation devices and methods reduce the cost of deep hole excavation. A spallation head has rotating, circumferentially spaced jets. The jets may be combustion flame jets or very hot water. In a combustion embodiment, air and water are delivered to the spallation apparatus downhole in a mixture, and are separated. In a low density embodiment, the borehole is essentially empty. In a high density embodiment, more water is included in the mixture of air and water, and the borehole is filled with fluid. Instead of combustion, the kinetic energy of flowing water at the spallation device can be used to power a turbogenerator that generates electric energy to heat the water and spall the rock. The jets may also be aimed and configured to fuse the excavation material, if spallation is not feasible. New lengths of feed and return pipe can be added while spallation continues uninterrupted, either due to well head alternating equipment, or a downhole relative motion device.

Abstract: The present invention is directed to an annulus access valve system for selectively opening and sealing an annulus bore in a wellhead apparatus comprising an annular bore insert sealingly and fixedly attached within the annulus bore; at least one flow port formed in the bore insert for establishing a fluid path through the annulus bore; an annular valve sleeve sealingly and slideably attached within the bore insert; and a hydraulic actuator for raising and lowering the valve sleeve over the flow port; whereby the sleeve may be actuated to open the flow port and thereby open the annulus bore and the sleeve may be actuated to close the flow port and thereby seal the annulus bore.

Abstract: A wellbore milling system has been invented which includes, in one aspect, a lower window mill, and two watermelon mills connected above the window mill. In one aspect the topmost of the two watermelon mills has a plurality of cutting blades with rough dressed outer surfaces and the lowermost watermelon mill has such blades with smooth outer surfaces. Such a system may be used in a multi-trip method with a starter mill first run into a wellbore to start a window to be milled by the window-watermelon-mills combination.