Abstract: A while drilling system and method for determining downhole parameters is provided. The system includes a retrievable while drilling tool positionable in a downhole drilling tool, a sensor chassis and at least one sensor. The while drilling tool is positionable in the downhole drilling tool and has a first communication coupler at an end thereof. The sensor chassis is supported in the drilling tool. The sensor chassis has a second communication coupler at an end thereof for operative connection with the first communication coupler. The sensor is positioned in the chassis and is adapted to measure internal and/or external parameters of the drilling tool. The sensor is operatively connected to the while drilling tool via the communication coupler for communication therebetween. The sensor may be positioned in the while drilling tool and retrievable with the drilling tool. Preferably, the system is operable in high temperature and high pressure conditions.

Abstract: A method and apparatus is disclosed for transmitting digital signals across safety transmission barrier. High data transfer rates are achieved for transfer from a safe certified device across the transmission barrier to a standard or non-rated device. A signal pair is generated including a first digital signal from the safe device and a second digital signal that is phase shifted from the first digital signal. Preferably, the second signal is phase shifted by 180 degrees, essentially being an inverted version of the first digital signal. The first and second digital signals are transmitted across the transmission barrier to a receiver in a safe area. An output signal is then reconstructed based on the falling edges of the first and second digital signals. The reconstructed signal closely approximates the first digital signal.

Abstract: A pressure pulse generator for a downhole drilling tool is provided. The pressure pulse generator includes a stator with an orifice through which a stream of fluid passes, and a rotor intended to rotate opposite the stator to allow the flow of more or less liquid exiting the orifice of the stator. The rotor is equipped with an orifice, and the two orifices present a communicating area for the passage of the stream of fluid. The rotor is capable of passing fluid therethrough. A turbine with blades rotatable in response to fluid flow through the rotor may also be provided. The turbine is operatively connected to the rotor via a drive shaft. The fluid flow through the rotor may be used to rotate the turbine and provide power usable in the downhole tool.

Abstract: An apparatus and a method for controlling oilfield production to improve efficiency includes a remote sensing unit that is placed within a subsurface formation, an antenna structure for communicating with the remote sensing unit, a casing joint having nonconductive “windows” for allowing a internally located antenna to communicate with the remote sensing unit, and a system for obtaining subsurface formation data and for producing the formation data to a central location for subsequent analysis. The remote sensing unit is placed sufficiently far from the wellbore to reduce or eliminate effects that the wellbore might have on formation data samples taken by the remote sensing unit. The remote sensing unit is an active device with the capability of responding to control commands by determining certain subsurface formation characteristics such as pressure or temperature, and transmitting corresponding data values to a wellbore tool.

Abstract: An electromagnetic coupling system is disclosed which includes a first electromagnetic transducer sealingly disposed in an outer wall of a tool mandrel, the mandrel adapted to be positioned in a drill collar. A second electromagnetic transducer is sealingly disposed in an interior of a port in the drill collar. The second transducer is positioned so that it is proximate the first transducer when the mandrel is positioned in the drill collar. A third electromagnetic transducer is sealingly disposed in an exterior of the port in the collar. The second and third transducers define a sealed chamber in the port. The second and third transducers are electrically coupled to power conditioning and signal processing circuits disposed in the chamber. A fourth transducer is positioned proximate the third transducer. The fourth transducer is electrically coupled to at least one of a sensor, an external communication line and an external power line.

Abstract: A method and apparatus is provided to determine downhole pressures, such as annular pressure and/or pore pressure, during a drilling operation. A bottom hole assembly (BHA) of a downhole tool includes one or more pressure equalizing assemblies capable of registering the pore pressure when the BHA is at rest and in contact with the wellbore, and annular pressure of a wellbore when it is not. Wellbore fluid is permitted to enter the pressure equalizing assembly and register an annular pressure measurement. Once the BHA comes into contact with the wellbore and to rest, fluid communication is established between the pressure equalizing assembly and the formation to generate a pore pressure measurement. The pressure equalizing assembly includes a sliding valve selectively moveable between an open and closed position in response to operation of the BHA so that the desired pressure measurement may be taken.

Abstract: A method and apparatus for collecting data downhole in a well bore, even during drilling operations, are disclosed. The apparatus generally comprises an antenna and some associated electronic circuitry. The antenna includes a plurality of arrayed transceiver elements and the electronic circuitry steers transmission or reception through the antenna by controlling the application of power to the array elements. In operation, a transceiver unit containing such an antenna is positioned proximate a remote sensor placed into a formation. An electromagnetic signal is then steered to communicate with the remote sensor over a wireless link.

Abstract: A method is disclosed for reducing noise in a measured telemetry signal. The method includes tracking a characteristic of at least one harmonic of a noise component in the measured telemetry signal band. The at least one harmonic has a frequency outside a telemetry signal band. The characteristic of the noise component is determined for at least one other harmonic thereof. The at least one other harmonic has a frequency inside the telemetry signal band. A noise reference is generated from the characteristic of the in band harmonic, and the noise reference is combined with the measured telemetry signal to generate a noise-canceled telemetry signal.

Abstract: A core sample retaining sleeve is provided for preventing loss of a cut core sample from the distal end of a coring bit, particularly during retraction of the coring bit to within the coring tool. Preferably, the core sample retaining sleeve is disposed concentrically within the coring bit to fit around the received core sample. The core sample retaining sleeve has one or more retaining fingers formed on the distal end of the coring bit. The retaining fingers are selectively closeable, preferably by urging the one or more retaining fingers against one or more guide members. A guide member is preferably provided as a stationary ridge on the inner, distal surface of the coring bit. The core sample is contained and protected within the closed retaining sleeve.

Abstract: A downhole tool for collecting data from a subsurface formation is disclosed. The tool is provided with a probe for testing and/or sampling an adjacent formation. The tool is also provided with a protector positioned about the probe for engaging and protecting the sidewall of the bore hole surrounding the probe. The protector prevents deterioration of the wellbore during the testing and/or sampling by the probe.

Abstract: A load cell for sensing deformation in a drill collar is provided. The load cell comprises a disc member having one or more arcuate apertures and a deformation sensing element disposed on a side surface of the arcuate apertures. The load cell is capable of sensing such drilling parameters as weight and torque on a drill bit during the drilling operation.

Abstract: A well logging instrument is disclosed which includes a housing operatively coupled to a well logging conveyance and movable within the wellbore. The housing has therein a formation testing system and an axial extension mechanism. The axial extension mechanism controllably extends and retracts to allow the formation testing system to perform tests and take samples in an axially fixed position in the wellbore while the housing moves through the wellbore.

Abstract: A robust, low-loss wired pipe joint is provided for service as a component of a wired pipe string for transmitting measurement data to a surface station from locations in a borehole in oil well drilling and oil well operations. Conductive layers reduce signal energy losses over the length of the drill string by reducing resistive losses and flux losses at each inductive coupler. The wired pipe joint is robust in that it remains operational in the presence of gaps in the conductive layer. A wired pipe joint includes an elongate tubular shank having an axial bore, a threaded box-end, and a threaded pin end.

Abstract: A method of forming a stator for a positive displacement motor. The method includes forming a liner that includes at least two resilient layers and at least one fiber layer, and the at least two resilient layers are positioned so as to enclose the at least one fiber layer. The liner is positioned in a stator tube, and the stator tube includes a shaped inner surface including at least two radially inwardly projecting lobes extending helically along a selected length of the stator tube. The liner is cured in the stator tube so that the liner conforms to the radially inwardly projecting lobes formed on the inner surface and to the helical shape of the inner surface. The curing forms a bond between the liner and the inner surface and between the at least two resilient layers and the at least one fiber layer.

Abstract: A method for determining the characteristics of a subterranean formation penetrated by an existing or drilled well is disclosed. The method uses a mathematical model to estimate formation parameters as fluid exits the formation through a hole and into the wellbore or tool. The model may be adapted to wells having a perforation extending from the wellbore into the formation by mathematically adjusting the perforation to the hole of the mathematical model. The formation properties may be estimated by mathematically eliminating the perforation and replacing it with an enlarged hole radius to simulate the mathematical model.

Abstract: An orienter, particularly on coiled tubing or small diameter drill pipe, includes a motor, turbine, or other device for selectively converting the rotational kinetic energy produced from fluid flow through the device to mechanical power, and applying the mechanical power to a downhole tool through a gear train for orienting the downhole tool. The orienter is utilized during directional drilling and other operations such as well intervention, fishing, and multilateral re-entry operations. The downhole tool preferably includes a steerable mud motor. In one embodiment, the direction of the borehole is controlled by azimuthal rotation of the orienter of the present invention in response to downlink commands from the surface by changing fluid flow rate through the orienter in a predefined series of steps.

Abstract: The present invention presents a method that effectively restores the real-time advantage of annular pressure while drilling (APWD) measurements taken during certain drilling operations that require the mud circulation pumps to be turned off (a “pumps-off” condition). APWD data, such as pressure measurements, is obtained from instruments and related electronics within the BHA. APWD data can be measured, stored and even processed in the BHA during a pumps-off condition for subsequent processing or communication of a reduced amount of data to the driller at the surface.

Abstract: The present invention provides an improved coring motor for use in obtaining a core sample from the side wall of a drilled bore hole. The present invention provides controllable rotation, extension and retraction of the coring bit relative to the side wall without complicated positioning linkages and with conservation of space for use in slim tools for use downhole.