Abstract: A rotary drill bit is provided for boring earth formations which includes a bit blank and a metal matrix secured to the blank. The metal matrix includes a filler material dispersed therein. Cutting elements are mounted on the exterior face of the bit, and substantially all of the exposed internal and external surfaces of the bit are coated with an erosion and abrasion resistant hardfacing material bonded to the metal matrix.

Abstract: An improved rotating drag bit for cutting plastic, sticky, water reactive and shale formations is devised by providing a plurality of large diamond cutters having a circular cutting face in excess of one inch in diameter. Each large cutter is provided with at least one hydraulic nozzle which in turn provides a directed hydraulic flow at the corresponding cutter face. The directed hydraulic flow is positioned to apply a force to the chip which tends to peel the chip away from the cutter face. In addition, the hydraulic flow is positioned with respect to the chip so as to apply an off-center torque to the chip which is used to peel the chip away from the cutter face and toward the gage of the bit. In particular, the nozzle defines a jet which is characterized by a direction and velocity of hydraulic fluid determined by the jet characteristics. The core is generally symmetric about its longitudinal axis and has a length along the longitudinal axis and width perpendicular thereto.

Abstract: An improved bit and method for cutting plastic and sticky rock formations, which tend to cause bit balling, is provided by a drag bit having a cutting face formed of a plurality of generally radially extending open arched blades. Each arched blade is provided with a cutting face and defines a cavity beneath the arched to the bit body. In a preferred embodiment, the cutting elements on the arched blade are a plurality of synthetic polycrystalline diamonds which are cut, sized and shaped to comformally fit with each other so as to present a substantially diamond-only surface as a cutting surface of the bit. Hydraulic nozzles are defined in the bit body beneath and azimuthally behind the arches formed by each blade. The nozzles direct hydraulic flow across the cavity under the arch and across each portion of the cutting face on the arch.

Abstract: In an oil well instrumentation system, the downhole sensor system is controlled by a computer which is powered-on only during sampling movement. An independent circuit, continuously powered, detects significant sensor rate-of-change values whereby the computer-sampling equipment is powered-on. A self-contained memory gauge includes either semiconductor or magnetic core memory for retaining downhole information related to sampled parameters, such as borehole temperature and pressure. A microprocessor-based computer manages the power utilization by independently and selectably energizing and deenergizing different sections of the gauge. The magnetic core memory is tested for operability, and the addressing of the magnetic core memory is adjusted in accordance with any inoperable memory locations.

Abstract: The present invention comprises a multi-barrel seismic source air gun module for use in a marine environment, preferably comprising a plurality of air gun barrels symmetrically disposed in a single plane about and rigidly secured to a control head containing means for actuating said barrels.

Abstract: The disclosure relates to a seismic vibrator having an airbag isolator, a transducer for monitoring the instantaneous air pressure within the airbags, a summer to add the pressures within each air bag and a calibrated weighting network to convert the composite pressure for display as holdown weight on a meter and for comparing the measured holdown against a preset threshold that is used to enable or disable sweep generation or operation of an inducer. The system also includes structure for comparing the measured holdown against a preset threshold that is used as a feedback signal to the lift system and for providing a signal proportional to holdown weight to the sweep generator for use as a feedback signal to modify the amplitude of the force generated by the actuator.

Abstract: A modular perforating gun employing only secondary explosives therein, of a design permitting guns to be made up in tandem like drill pipe. The tandem guns have no physically connected shaped charge initiating devices therebetween, each gun being actuated by an acceptor booster charge which is initiated by a shaped donor charge at the bottom of the next higher gun.

Abstract: A radioactivity shielding assembly, suitable for transferring a radioactive substance with a reduced risk of human exposure and environmental contamination, includes a protective shield casing having a reservoir disposed in the casing for receiving the radioactive substance. Associated with the casing is a coupling structure for coupling the reservoir and casing directly to a receiver into which the radioactive substance is to be transferred. The casing includes a side shielding structure in which the reservoir is retained and two end shield structures which are removably attached to the side shield structure. The two end shield structures are removed from the side shield structure at the location at which the radioactive substance is to be discharged, but such removal leaves the reservoir protectively received in the side structure to maintain continued protection against radioactive exposure or contamination. A related method of transferring the radioactive substance is also described.

Abstract: A fluid testing apparatus comprises a container for holding a fluid to be tested and a member disposed within the container so that the member is rotatable within a fluid to be tested within the container. The container has a wall defining a cavity into which the member extends. A magnetically responsive rotor is mounted on this end of the member. Immediately adjacent the outside surface of this wall, a plurality of stator poles are secured so that a field generated in the stator poles directly interacts with the rotor across the wall to rotate the member. The rotor and stator poles are preferably of a stepper motor.

Abstract: The disclosure relates to a solenoid valve for an air gun which substantially increases the rate at which maximum air flow is achieved. The new valve structure includes a coil actuated plunger, which is preferably solid and formed of a magnetically permeable material and closes an annular 360 degree port opening between the valve inlet and valve outlet when in the unactuated state. This plunger position is maintained by a biasing spring which forces the forward annular sharp plunger edge against a face seal in the nose of the valve, thereby sealing the valve input port from its output port. Upon actuation of the solenoid valve coil, the plunger is moved against the bias of the spring very rapidly, thereby speedily uncovering the channel between inlet and outlet and permitting rapid 360 degree communication between the inlet and outlet to permit maximum air flow therebetween and out of the outlet port.

Abstract: A downhole tool for an oil or gas well includes a self-contained power supply having a housing in which a primary fuel source, a Stirling cycle engine, and a linear alternator are disposed. The primary fuel source includes a radioisotope which, by its radioactive decay, provides heat to operate the Stirling engine which in turn drives the liner alternator to provide a suitable electrical output for use by the circuit of the downhole tool.

Abstract: A sensor apparatus includes a pressure sensor, a reference device and a temperature sensor collocated within a common environment. The reference device and the temperature sensor are constructed to have temperature response times matched to the temperature response time of the pressure sensor to compensate for temperature gradients produced either by external heating or by pressure-volume heating.

Abstract: An acceleration sensor uses a capsule of mercury filling a rigid enclosure with pressure sensors responsive to inertial forces exerted by the mercury on the walls of the enclosure when it is caused to accelerate. The enclosure may have a flexible lining on its walls or contain a flexible bag for holding the mercury. Means are provided for producing a bias pressure in the mercury. The enclosure may be cubic or tetrahedral, for example, and the outputs of the pressure sensors additively combined to produce outputs representing accelerations in required orthogonal directions when these differ from the directions to which the sensors are responsive. A rotational acceleration sensor is also described.

Abstract: An input/output command processor provides a sophisticated communication link between a central processor and peripheral digital apparatus. The command processor receives commands from the central processor, interprets them and transmits them to the peripheral digital apparatus. The command processor is comprised of a store/fetch circuit for directly accessing the memory of the central processor; a fetch and buffer circuit for causing a fetch and for temporarily storing the results of the fetch (commands) in a buffer register file; an interpret controller for interpreting the commands and routing them to the cognizant peripheral apparatus, according to their function.

Abstract: The present invention comprises a novel, improved connector mechanism for connecting a probe and a pipe string portion of a wireline based data transmission system. The connector mechanism includes cooperating pin and channel means, one of said means associated with the probe and the other with the pipe string portion. The connector mechanism is especially suited for use in conjunction with a combined tubing conveyed perforating and drill stem testing operations due to the present invention's resistance to unwanted disengagement responsive to jarring or shock waves such as are generated by perforating guns.

Abstract: A flow controller apparatus having few moving parts that may be inserted directly into a flow line to be responsive to flow pressure and maintain the flow rate constant. The flow controller consists of a tubular frame section having an internal bore that is a revolutional chamber having a maximum cross-sectional diameter at the inlet end and tapering, either linearly or non-linearly, toward a minimum cross-sectional area across a throat portion. A control rod and differential pressure plate supported axially movably in said chamber is spring biased toward the inlet end of the chamber, and is movable in response to upstream flow pressure to adjust the cross-sectional fluid flow area to maintain a constant flow rate.

Abstract: The present invention comprises a rapid cycle tester valve operable in response to annulus pressure. The tester valve includes a valve ball rotatable between open and closed positions through an operating mechanism which includes a ball and slot ratchet mechanism for selectively transmitting operating movement from a pressure responsive slidable valve housing through a mandrel assembly. The valve housing employs back to back check valves disposed in a longitudinal valve passage to create pressure differentials to move the valve housing in response to annulus pressure increases and decreases.

Abstract: The high pressure gauge carrier of the present invention uses an outer gauge carrier housing having disposed therein a pressure-tight inner housing carrying a temperature gauge in the interior thereof. The inner housing is substantially filled with a compressible liquid, and the pressure tight connections of the inner housing incorporated metal to metal seals in order to eliminate the failure of elastomeric seals at the elevated temperatures encountered by the gauge carrier.

Abstract: A method and apparatus for generating foam in a well bore, the apparatus being a foam generator comprising a tubular body having a plurality of apertures circumferentially spaced about the wall thereof, the tubular body containing a choke therein disposed above said apertures as the foam generator is positioned in the well bore. The foam generator is located in a tubing string in the well bore, preferably with at least one stand of tubing between it and the area of the well bore to be treated with the foam. The liquid component of the foam, which may or may not carry solid particles such as fracturing proppants, is pumped down the well bore annulus, while the gaseous component of the foam is introduced through the tubing string.

Abstract: A differential fill valve assembly for application in float collars or shoes in well casing. The valve assembly comprises a back pressure flapper valve disposed within a substantially tubular upper housing, and a lower housing containing an activating sleeve slidably disposed therein above a double flapper valve assembly. The activating sleeve initially extends into the upper housing to a sufficient extent to maintain the flapper valve in an open position and comprises a lower tubular sleeve surmounted by a circumferential ring of longitudinally upwardly extending collet fingers having radially inwardly extending shoulders thereon, said fingers and shoulders having elastomeric inserts extending therebetween; the activating sleeve is maintained in this position through use of shear pins, by which it is secured to a support ring associated with the lower housing.