Abstract: There is described an improved apparatus for azimuthal orientation of a tool in a wellbore. The apparatus comprises a tubular housing, a mandrel rotatably supported in the tubular housing and extending therefrom for connection to a tool for rotation thereof, a piston mandrel axially aligned with and connected to the mandrel, a piston longitudinally movable in an annulus between the piston mandrel and the tubular housing and being non-rotatable relative to the tubular housing, at least one pin longitudinally movable in concert with the piston arranged to track in respective helical grooves in the mandrel causing rotation of the mandrel in response to longitudinal movement of the pins, and a flow path for selective delivery of pressurized hydraulic fluid to either side of the piston for rotating the mandrel in either the clockwise or counterclockwise directions, or to both sides of the piston equally to maintain the mandrel in a fixed annular orientation.

Abstract: Corrosion, scale-formation, or other deleterious processes are inhibited in an oil well by installing within the oil well (10) fluid-permeable elements, such as tubular filters (20), which comprises a suppressing material. Each filter (20) comprises two tubular filter screens (24) between which is a bed (26) of particles comprising suitable inhibitor material. The particles might for example be porous ceramic spheres impregnated with the inhibitor material. The inhibitor material gradually dissolves in the well fluids during operation, and may for example inhibit corrosion and/or scale formation.

Abstract: An earth-boring bit has a bit body that is threaded at one end for connection into a drill string. At least one cantilevered bearing shaft depends inwardly and downwardly from the bit body. A cutter is mounted for rotation on each bearing shaft and includes a plurality of cutting elements arranged in generally circumferential rows. At least one wear-resistant element is secured to the bit body between the lower end of the bit body and the threaded end, the wear-resistant element being elongate or generally oblong in cross-section.

Abstract: A drill bit for percussive drilling includes a front surface in which cutting inserts are mounted. A recess is formed in the front surface, and a fluid channel extends through the drill bit for supplying flushing fluid to the recess. The recess is completely bordered by an endless land. Some of the cutting inserts are mounted in the land. Others of the cutting inserts are mounted in the recess in order to be cooled and flushed by a cushion of flushing fluid created in the recess.

Abstract: A downhole device and method for performing a function in a well. The device has a series of dedicated hydro-mechanical locks that prevent occurrence of an associated function. The hydro-mechanical locks are capable of being released directly by a respective elevated hydraulic activating pressure condition, and are constructed and arranged for sequential operation, such that a successive lock in the series cannot be released until after the hydraulic pressure condition required to release the preceding lock in the series has occurred. In a preferred embodiment, an actuator sequentially releases each lock in a series of locks, subsequently moving an operator to perform a function. A preferred implementation employs a series of resilient rings movable, sequentially, from a locking to an unlocking position, and a common actuator that effects these movements.

Abstract: A pressure compensated plug for use with subsea trees is described in which a reservoir of compressible fluid is located from a cavity within a horizontal tree (10) whereby allowing temperature induced volume changes to be absorbed by the compressible fluid without resulting in significant increase in pressure. This is achieved by providing a pressure compensation apparatus (80) in the cavity, the apparatus comprising a housing (82) with a floating piston (86) in a chamber (84). The lower face (96) of the chamber is exposed to compressible fluid in the form of an inert gas, such as nitrogen, which is pre-charged at the surface to the appropriate hydrostatic pressure of the seabed. The volume of gas trapped between the lower piston face and the lower face of the cylinder forms the gas reservoir (94). A compensation cylinder can be attached to the upper section of the lower plug (70) and run and retrieved at the same time as the plug, thereby reducing the number of intervention runs.

Abstract: A sampling device includes a barrel having a downhole end, an exterior surface, an interior surface defining a hollow interior, and an open end at the downhole end of the hollow interior. A fluid entrance penetrates the exterior surface. A fluid path having an outlet port is fluidly coupled to the fluid entrance. The device is driven into a subsurface so that a soil sample is forced into the hollow interior. While the device is still in the subsurface a fluid sample is collected through the least one fluid entrance and fluid path.

Abstract: The present invention is an improved apparatus for controlling the weight on the drill bit during operation. In this invention, an inner mandrel has a telescoping movement in response to added drill string length at the surface. As the inner mandrel telescopes closed, it approaches a restrictor which is fixedly disposed in the lower housing of the drill string assembly. When the inner mandrel mates with the restrictor, a stand-pipe pressure increase noticeable to the operator occurs. The operator then stops the drill string and allows the motor to drill ahead. As the motor drills ahead, the inner mandrel telescopes open and the operation is then repeated.

Abstract: A mechanical set anchor wherein a plunger extending from a base end of an anchor body activates a pin type trigger which releases a spring utilized to set multiple slips extending from the body of the anchor. Continued downward compressive forces fully sets the slips into the borehole pipe casing. The slips are maintained in their fully set position by a locking nut. The slips are further set into the pipe casing after slips are released from the anchor body. The anchor is mechanically released by an upward pull under tension of sufficient strength to shear release pins that release the compressed spring fully retracting the slips within the anchor body so that the anchor may be tripped from the borehole without interference from the previously engaged slips.

Abstract: An apparatus and method for collecting and retrieving liquid samples is disclosed. The sampling apparatus or bailer can reliably collect and retrieve liquid samples from a reservoir such as a liquid filled borehole. The sampling apparatus is mechanically simple, reliable, inexpensive to manufacture, and can optionally be discarded after one sampling operation thereby eliminating the time consuming and expensive step of cleaning the bailer prior to the next sampling operation. Furthermore, weighting is employed to assist in lowering the bailer into the reservoir of liquid to be sampled, wherein the weighting material is isolated from the interior sample chamber of the bailer in order to avoid contamination of the sample by the weighting material. The bailer can be easily emptied of sample liquid thereby minimizing operational costs associated with sampling activities.

Abstract: A well plunger system for the production of natural gas is described. The well plunger system includes a closed loop controller for the production of natural gas. 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 differential pressure sensor positioned in the sales line, a motor for operating the valve, a first pressure sensor positioned in the tubing line and a second pressure sensor positioned in the sales line. The controller opens the valve based on an open pressure difference which is the difference between the pressure of gas in the tubing line and the pressure of gas in the sales line.

Abstract: An arrangement and associated method for thermally protecting an electronic component assembly from heat at least to a limited extent is disclosed herein. The electronic component assembly includes a plurality of thermally sensitive electronic devices, each of which is constructed such that when the device is in a powered state there is a maximum operating temperature to which it may be subjected without causing thermal damage and such that when the device is in a non-powered state there is a higher maximum non-operating temperature to which the device may be subjected without causing thermal damage. During powered operation of the assembly, the temperature is sensed at a predetermined position in close proximity to the devices.

Abstract: An underground propelling method uses a propellant apparatus including a propellant head having a pressure receiving face portion inclined relative to an axis of the head and a plurality of propellant cylinders flexibly and pivotally connected in series to a rear end of the propellant head. The propellant apparatus is propelled under the ground by applying a thrust to the propellant apparatus from behind. Each propellant cylinder of the apparatus is pivotal about a single pivot axis thereof alone. The apparatus is propelled with the pressure receiving face portion thereof being oriented along a pivotal direction of the propellant cylinder about the pivot axis.

Abstract: A composite body cutting instrument formed of a polycrystalline diamond layer sintered to a carbide substrate with a carbide/diamond transition layer. The transition layer is made by creating carbide projections perpendicular to the plane of the carbide substrate face in a random or nonlinear orientation. The transition layer manipulates residual stress caused by both thermal expansion and compressibility differences between the two materials and thus increases attachment strength between the diamond and carbide substrate by adjusting the pattern, density, height and width of the projections.

Abstract: A rolling cutter drill bit has at least one roller cutter mounted on a cantilevered bearing shaft with a sealed bearing and lubrication system, lubricant pressure balancing means, lubricant pressure relief means, and a volume compensating rigid face seal assembly axially movable through an operating range. The face seal assembly comprises two cooperating face seal rings, one ring mounted on the bearing shaft and the other ring mounted in the cutter; a first energizer for the seal ring mounted on the bearing shaft, having a stiffness K1; and a second energizer for the seal ring mounted in the cutter, having a stiffness K2. In order to minimize the variation in the sealing face force as the assembly moves through its operating range, the stiffness K2 is less than half, and preferably less than 0.2, of the stiffness K1.

Abstract: An anti-whirl rotary drag bit including one or more cutters, wear knots or other support structures disposed on the flank of a bit profile in a normally cutter-devoid region of the profile adjacent the gage of the bit in the circumferential segment of the gage used as a bearing zone for the bit to ride against the side of the bore hole. Such flank cutters or other structures reduce wear of the bearing zone but, due to their placement, do not come into play except under certain drilling situations such as reaming or high rates of penetration wherein whirl tendencies resulting from cutting forces are not as pronounced.

Abstract: An isolation system is disclosed which includes a production screen and an internal isolation pipe sealed with the production screen at proximal and distal ends, and an internal sleeve slidably coupled with the isolation pipe. The isolation pipe defines at least one port and the sleeve defines at least one aperture, and the sleeve is moveable between an open position in which the port and aperture are in communication to permit fluid flow therethrough, and a closed position in which the port and aperture are not in communication and fluid flow is prevented. The sleeve is manipulated by a service string and multi-action shifting tool between the opened and closed positions. Also disclosed is a gravel packer and method of operation incorporating the isolation system, as well as a service tool and service string assembly useful therewith.

Abstract: Improved techniques are provided for controlling the injection of a cellulose powder/water mixture input into a formation through an injection well for recovery of hydrocarbons. The initial dosing rate of powder added to the water is increased as a function of both the monitored pressure of the mixture in the wellbore in the vicinity of the formation, and the monitored flow rate of the injected mixture. The water flow rates and the flow dosing rates are optimised, and the mixture is controlled to obtain setting within the formation to enhance the recovery of hydrocarbons. A mixing tank is designed to prevent premature setting of the mixture. Portable equipment is provided for injecting the powder/water mixture into the formation, thereby increasing the versatility of the equipment reducing the overall costs of the recovery operation.

Abstract: A method and apparatus for removing solids from a substantially horizontal section of a wellbore which allows the use of coiled tubing as a workstring without requiring the removal of the production tubing from the wellbore. Guide tubing, which is left in the wellbore, extends from the surface through the horizontal section and is adapted to guide a string of slightly smaller-diameter, coiled tubing through the horizontal section. Wash fluid, e.g. water, flows through a nozzle on the coiled tubing and out through openings in the guide tubing directly into the solids to form a slurry therewith. The slurry is then pumped out of the wellbore through the production tubing and/or reenters the guide tubing through other opening(s) therein to flow to the surface through the annulus which exists between the coiled tubing and the guide tubing.

Abstract: A facility or platform (11) having a limited number of circular well-drilling slots (3) is converted to provide additional well-drilling locations on the platform (11) while protecting the platform (11) from the hoisting and lowering loads normally required to drill deep water wells. The additional well-drilling locations are provided by placing multiple wells in individual slots (3). Load protection is accomplished by transferring such loads to a underwater competent earth formation (15) with a thick-walled shroud (12). The shroud (12) surrounding the multiple wells carries at minimum by a plurality of internal centers through which the wells pass for assuring separation of the multiple wells and transmitting loads to the shroud (12).