Abstract: A method and system for drilling a wellbore is described. The system includes a wellbore with a variable density drilling mud, drilling pipe, a bottom hole assembly disposed in the wellbore and a drilling mud processing unit in fluid communication with the wellbore. The variable density drilling mud has compressible particles and drilling fluid. The bottom hole assembly is coupled to the drilling pipe while the drilling mud processing unit is configured to separate the compressible particles from the variable density drilling mud. The compressible particles in this embodiment may include compressible hollow objects filled with pressurized gas an configured to maintain the mud weight between the fracture pressure gradient and the pore pressure gradient. In addition, the system and method may also manage the use of compressible particles having different characteristics, such as size, during the drilling operations.

Abstract: An apparatus (3) for use when gathering parameters from a well flow in a petroleum well (1) in order to be able to evaluate the flow and productivity or injectivity of the well is described, the apparatus (3) including: —a semi-rigid rod (5) arranged in a manner allowing it to sense the temperature profile of the well (1); —at least two mutually spaced-apart measuring devices and/or fluid phase indicators (9) attached to the semi-rigid rod (5); and —at least one pressure sensor (11) arranged in a manner allowing it to sense pressure in the well (1), whereby the amounts of water, oil and gas from one or more formation sections may be quantified. A method of using the apparatus is also described.

Abstract: The present invention relates to a measurement-while-drilling (MWD) tool having a pressure compensation system and reservoir segregated from fluid integration with actuator mechanism lubricants. The MWD tool can also be serviced on the rig floor without the need to drain, reseal and charge the compensation system.

Abstract: A method and computer program product of either preventing or minimizing pore pressure increase near the wellbore wall within argillaceous formations through which a borehole has been drilled. By interpreting relevant drilling experience data, the type, extent and time-dependency of wellbore instability mechanisms are determined. The impact of drilling mud designs on the time-dependent wellbore instability and hole enlargement is determined by back-analyzing observed drilling events. At least one field-based criterion relationship between net mud weight reduction percentage ratio and hole enlargement is determined. A maximum allowable percentage ratio(s) of net mud weight reduction and either breakout mud weight or mud weight used for the adopted maximum hole enlargement that the wellbore may experience during drilling is determined. Drilling mud salinity value and salt type to satisfy maximum allowable percentage ratio(s) is then determined.

Abstract: The present invention relates to a measurement-while-drilling tool [2] with a mechanically driven poppet [216] which eliminates the flow of drilling fluid through the tool, and reliance on surface supplied hydraulic force to activate the poppet [216]. The present invention eliminates the pilot valve system, and generates a fluid pulse from a direct drive relationship between a reversible motor [414], actuator [300], and poppet valve [216]. A pulser [200] has a push rod [214] slidably located inside. Poppet [216] is located on the push rod [214]. Actuator [300] is connected to the pulser [200], and has a ball screw [334] mechanically connected [330] to the push rod [214]. An electric motor [414] and gear train is operatively connected [338] [340] [342] to the ball screw [334]. Motor [414] generates linear movement of the poppet [216] in relation to an orifice [112] to restrict flow and generate a pulse.

Abstract: A closed-loop circulating system for drilling wells has control of the flow rates in and out of the wellbore. Kicks and fluid losses are quickly controlled by adjusting the backpressure. Kick tolerance and tripping margins are eliminated by real-time determination of pore and fracture pressure. The system can incorporate a rotating BOP and can be used with underbalanced drilling.

Abstract: The present invention relates to a measurement-while-drilling (MWD) tool having a pressure compensation system and reservoir segregated from fluid integration with actuator mechanism lubricants. The MWD tool can also be serviced on the rig floor without the need to drain, reseal and charge the compensation system.

Abstract: A method includes sensing a parameter in a well using a sensor disposed on a drillstring, determining a position of the sensor in a wellbore based on a position of the sensor in the drillstring and a position of the drillstring in the wellbore.

Abstract: A downhole telemetry system for use in a wellbore including borehole fluid. The system includes a stator including flow channels though the stator and a rotor including flow channels though the rotor. The rotor is rotatable on a drive shaft by the force of the borehole fluid flowing through the rotor. The rotation of the rotor creates pressure variations in the borehole fluid related to the movement of the rotor channels relative to the stator channels, thus forming a carrier wave. A regulating system adjusts the amount of fluid force on the rotor for a given flow rate of borehole fluid to maintain the frequency of the carrier wave within a range of a target frequency. Also, an alternator drivable by the rotation of the drive shaft provides power to the system. The system also includes an encoder capable of adjusting the rotation of the rotor to modulate the carrier wave.

Abstract: A method to control borehole fluid flow includes detecting a drilling condition and operating at least one valve in the drill string to place an exterior of the drill string in fluid communication with an interior of the drill string in response to detecting the drilling condition.

Abstract: Disclosed herein is a method of detecting a downhole washout. The method includes, positioning a plurality of sensors along a downhole drillstring, communicatively coupling the plurality of sensors to a processor, and analyzing data sensed by the plurality of sensors with the processor for relationships indicative of a washout.

Abstract: Embodiments of systems, program products, and methods for controlling drilling fluid parameters are provided. These embodiments, for example, provide dynamic density control with highly adaptive, real-time, process-control and are scalable to any rig, large or small, on land or water. Combined static and dynamic stresses and displacements can be determined continuously at strategic locations in and around the wellbore of a well so that insitu and operational induced pressure window limitations at specific weak-points or other locations of interest are controlled.

Abstract: A method for controlling formation pressure during drilling includes pumping a drilling fluid through a drill string in a borehole, out a drill bit at the end of the drill string into an annular space. The drilling fluid is discharged from the annular space proximate the Earth's surface. At least one of a flow rate of the drilling fluid into the borehole and a fluid flow rate out of the annular space is measured. Pressure of the fluid in the annular space proximate the Earth's surface and pressure of the fluid proximate the bottom of the borehole are measured. Pressure of the fluid proximate the bottom of the borehole is estimated using the measured flow rate, annular space pressure and density of the drilling fluid. A warning signal is generated if difference between the estimated pressure and measured pressure exceeds a selected threshold.

Abstract: Methods and systems are disclosed for downhole processing of measurements made in a wellbore during the construction of the wellbore. The system includes sensors located downhole adapted to measure downhole parameters. The system uses a downhole processor to calculate a statistical relationship, preferably covariance, between the two downhole parameters. A transmitter located downhole and in communication with the downhole processor is used to transmit the calculated statistical relationship to the surface. At the surface the statistical relationship is compared with surface acquired data and surface drilling operating parameters are altered based on the statistical relationship.

Abstract: A method for the detection of gas invading a wellbore during drilling by the influx of fluids which contain gas from the formations penetrated by a wellbore.

Abstract: A rotating control drilling device includes an upper sealing element and a lower sealing element positioned around a drillstring and forming a chamber therebetween and a leak detection device. The leak detection device includes a piston in communication with the chamber, a magnet disc disposed on an end of the piston, and a plurality of magnetic sensors arranged in a magnetic sensing ring around the rotating control drilling device. Upon reaching a selected critical pressure in the chamber, a spring is configured to compress as the magnet disc is positioned proximate to the plurality of magnetic sensors. Furthermore, a method to detect leaks in a rotating control device includes positioning a leak detection device in communication with a chamber located between upper and lower sealing elements and signaling with the leak detection device when a pressure of the chamber exceeds a selected critical pressure.

Abstract: A system and method is provided for a low profile rotating control device (LP-RCD) and its housing mounted on or integral with an annular blowout preventer seal, casing, or other housing. The LP-RCD and LP-RCD housing can fit within a limited space available on drilling rigs.

Abstract: A method and apparatus for predicting and controlling secondary kicks, while dealing with a primary kick experienced when drilling an oil and gas well. The method includes a step of determining whether a different pressure per cubic meter of mud pit volume has been caused by a secondary kick by subtracting shut in drill pipe pressure (SIDPP) from shut in casing pressure (SICP) and dividing the derived sum by a kick volume in KPa per cubic meter from the primary kick. A further step is then taken of increasing casing pressure until casing pressure equals pit gain times (X) rate of change in casing pressure per cubic meter of pit gain plus (+) SIDPP.

Abstract: The invention is directed to a controllable pressure reducing valve (1) having a housing (2) which includes an inner chamber (3) extending in the direction of a longitudinal axis and having an inlet opening (15) and an outlet opening (17), said inlet opening (15) and said outlet opening (17) opening into the inner chamber (3) at an axial relative distance, and said inner chamber (3) including between the mouths of the inlet opening (15) and the outlet opening (17) at least one annular wall (11) having a cylindrical valve bore (20) and an axially movable valve body (4) which is arranged in the inner chamber (3), extends through the valve bore (20) and has a piston-type portion (29) guided in the valve bore (20) and adapted to close the valve bore (20). The piston-type portion (29) includes at least one control recess (45) bounded by a control step (46) which extends in axial direction and in circumferential direction and combines with an edge of the valve bore (20) to form a controllable valve opening.

Abstract: A method and system for drilling a wellbore is described. The system includes a wellbore with a variable density drilling mud, drilling pipe, a bottom hole assembly disposed in the wellbore and a drilling mud processing unit in fluid communication with the wellbore. The variable density drilling mud has compressible particles and drilling fluid. The bottom hole assembly is coupled to the drilling pipe while the drilling mud processing unit is configured to separate the compressible particles from the variable density drilling mud. The compressible particles in this embodiment may include compressible hollow objects filled with pressurized gas an configured to maintain the mud weight between the fracture pressure gradient and the pore pressure gradient. In addition, the system and method may also manage the use of compressible particles having different characteristics, such as size, during the drilling operations.

Abstract: The invention relates to a pumping system for transporting drilling mud during the driving or sinking of bores. In said system, the pump assembly is interactively connected to the rotary drive unit (6) by means of gearing (5) that comprises driving gear (9) and driven gear (4).

Abstract: A non-contact measuring system using emitted and received electromagnetic radiation or microwaves is mounted on the return line carrying oil drilling mud and cuttings from an oil drilling apparatus. The system measures the height and flow of the mud and cuttings in the pipe. In one embodiment, it is mounted to the pipe in a low profile manner to protect it, and it uses a reflective surface to reflect the signal to the flow being measured.

Abstract: The present invention provides method for detecting the possible presence of surfaces layers of diagenetic origin by establishing divergence between well signatures such as logs, particularly for use in predominantly carbonate reservoirs.

Abstract: A method of determining drilling fluid contents including fractionating a fluid sample, wherein the fluid sample includes a drilling fluid, and collecting image data from the fractioned fluid sample. Furthermore, processing the image data with a process station to produce a rendered image, and outputting the rendered image. Additionally, a system for determining drilling fluids content including an image gathering vessel having a holding section and an image gathering device operatively coupled to the image gathering vessel for collecting image data from a fluid sample, wherein the fluid sample includes a drilling fluid. Furthermore, a processing station for receiving the image data from the image gathering device and for producing a rendered image of the fluid sample based on the image data.

Abstract: A testing apparatus comprising: a chamber (5) having an inlet (6) and an outlet (16); a measuring device (4), at least a part of which is provided within said chamber; wherein the inlet is arranged to direct fluid onto said part of the measuring device within the chamber in order to clean the measuring device during start up. Thus the density or viscosity of drilling mud may be continuously monitored. Preferred embodiments include an outlet valve such as a ball valve (7) with a bore defined therein. The bore allows fluid to flow therethrough even in a valve “closed” position and so generates the preferred back pressure whilst minimising the risk that the valve will block. A pressure activated drain valve (9) is also provided to substantially empty the chamber when not in use. When the apparatus is reactivated, an inlet tube is adapted to jet air and then fluid at the measuring device in order to remove debris therefrom. Thus the apparatus has the important benefit of self cleaning during start-up.

Abstract: Apparatus and methods to perform focused sampling of reservoir fluid are described. An example method couples a sampling probe to a subterranean formation and, while the sampling probe is coupled to the subterranean formation, varies a pumping ratio of at least two displacement units to reduce a contamination level of a formation flu id extracted via the sampling probe from the subterranean formation.

Abstract: A modular tool for use in subterranean formations includes a first module, a second module and one or more connectors for connecting the first and second modules. In particular, the first module includes a first collar that at least partially defines an exterior of the tool and that includes a first engagement mechanism at a first end of the collar and a second engagement mechanism at a second end of the collar. The first module also includes a fluid passageway for passing drilling fluid therethrough. The second module has a similar configuration as includes similar architecture. The one or more connectors facilitate the connection of at least one flowline fluidly connected to an exterior of the tool, and an electrical pathway for transmitting power and/or data between the modules.

Abstract: A system for testing a drilling fluid including a vessel having a fluid inlet, a filtrate outlet, a fluid outlet, and at least one permeable media disposed within the vessel. The system further including a base fluid container in fluid communication with the fluid inlet, a test fluid container in fluid communication with the fluid inlet, a filtrate container in fluid communication with the filtrate outlet, and a collection container in fluid communication with the fluid outlet. Additionally, the system includes a data acquisition device configured to receive data from at least one of the vessel, the fluid container, the filtrate container, and the collection container. Also, a method for determining sealing characteristics of a drilling fluid including injecting a test fluid having a fluid loss control material from at least fluid container to a vessel, the vessel having a permeable media having two plates disposed to create a variable gap.

Abstract: A system and method is provided for converting a drilling rig between conventional hydrostatic pressure drilling and managed pressure drilling or underbalanced drilling using a docking station housing mounted on a marine riser or bell nipple. This docking station housing may be positioned above the surface of the water. When a removable rotating control device is remotely hydraulically latched with the docking station housing, the system and method allows for interactive lubrication and cooling of the rotating control device, as needed, along with a supply of fluid for use with active seals.

Abstract: In an underbalanced drilling system and method, a change is induced in flowing bottom hole pressure in a wellbore. Data of the surface flow rate of effluent is then measured in response to the induced change. This measured data is obtained using a multi-phase flow meter before a separator of the underbalanced drilling system. Algorithms in computer software analyze the flowing bottomhole pressure and the measured surface flow rate data and determine both permeability and formation pressure for a portion of the wellbore in real-time during the underbalanced drilling operation. Ultimately, portion of the wellbore is characterized with the determined permeability and formation pressure.

Abstract: An apparatus (1) is described for the condition checking of a screen cloth in a vibrating screen for drilling fluid, comprising a pump (2) for drawing a drilling fluid sample from the bottom tray of the vibrating screen into the apparatus (1); a filter (3) for filtering the drilling fluid sample; and a pressure gauge (4) for measuring the pressure difference across the filter (3). A method is also described for the condition checking of a screen cloth in a vibrating screen, comprising drawing a drilling fluid sample from the bottom tray of the vibrating screen; filtering the drilling fluid sample through a filter (3); and measuring the pressure difference across the filter (3).

Abstract: Drilling system and method for drilling a bore hole into an earth formation, the bore hole having an inside wall. A drill string reaches into the bore hole and leaves a drilling fluid return passage between the drill string and the bore hole inside wall. A drilling fluid discharge conduit is in fluid communication with the drilling fluid return passage, and pump means are provided for pumping a drilling fluid through the drill string into the bore hole and to the drilling fluid discharge conduit via the drilling fluid return passage. The drilling fluid back pressure is controlled utilizing back pressure control means for controlling back pressure means. The system further provides fluid injection means comprising an injection fluid supply passage fluidly connecting an injection fluid supply with the drilling fluid return passage and further comprising an injection fluid pressure sensor arranged to provide a pressure signal in accordance with an injection fluid pressure in the injection fluid supply passage.

Abstract: A protection system is provided that mitigates damage caused by slug flow in oil and gas production systems. The protection system opens or closes a choke valve based upon flow parameters such as the separator pressure and level, and the riser pressure. The choke valve position is calculated based upon a number of factors of the production system in order to maintain efficiency while providing safety.

Abstract: A closed-loop circulating system for drilling wells has control of the flow rates in and out of the wellbore. Kicks and fluid losses are quickly controlled by adjusting the backpressure. Kick tolerance and tripping margins are eliminated by real-time determination of pore and fracture pressure. The system can incorporate a rotating BOP and can be used with underbalanced drilling.

Abstract: Methods and systems are disclosed for downhole processing of measurements made in a wellbore during the construction of the wellbore. The system includes a sensors located downhole adapted to measure a two downhole parameters. The system uses a downhole processor to calculate a statistical relationship, preferably covariance, between the two downhole parameters. A transmitter located downhole and in communication with the downhole processor is used to transmit the calculated statistical relationship to the surface. At the surface the statistical relationship is compared with surface acquired data and surface drilling operating parameters are altered based on the statistical relationship.

Abstract: A method and apparatus for signalling the surface operator about downhole conditions. Sensors located downhole collect data while drilling and the data is processed to determine bit failure, for example. When the sensor data indicates a failure, the pressure of drilling mud is varied using a valve on the downhole unit, and this pressure variance is indicated by a pressure gauge visible to the operator. This pressure change tells the operator a failure has been indicated.

Abstract: Drilling a bore hole comprises rotary drilling at a first rotation rate until a first target value is substantially met, changing the first rotation rate to a second rotation rate when a trigger is substantially met, and then drilling at the second rotation rate until a second target value is substantially met. Preferably, the second rotation rate is substantially zero, so the drilling at the second rotation rate is slide drilling. Finally, the steps of rotary drilling at a first rotation rate, changing the rotation rate to a second rotation rate, and drilling at the second rotation rate are repeated.

Abstract: A zone isolating and testing apparatus comprising an isolation tool and a downhole flow control means and a method of using such apparatus. The zone isolating and testing apparatus is particularly useful for testing zones during reverse circulation drilling using concentric drill string such as concentric drill pipe or concentric coiled tubing. The isolation tool of the zone isolating and testing apparatus comprises an expandable packer means and is adapted to connect to concentric drill string near the drilling means and be in fluid communication with the concentric drill string. The downhole flow control means of the zone isolating and testing apparatus comprises at least two valves, one for closing off the annular conduit between the inner tube and outer tube of the concentric drill string and the other for closing off the inner conduit of the inner tube.

Abstract: Techniques for detecting a kick in a borehole include acquiring a set of measurements with a sonic tool in the borehole; determining borehole mud slowness from the set of measurements; and comparing the mud slowness with a selected criterion, wherein the determining the mud slowness includes determining fluid mode slowness as a function of frequency for at least one fluid mode, and determining the mud slowness from the fluid mode slowness.

Abstract: A downlink system that includes at least one mud pump for pumping drilling fluid from a drilling fluid storage tank to a drilling system, a standpipe in fluid communication with the mud pump and in fluid communication with the drilling system, and a return line in fluid communication with the drilling system for returning the drilling fluid to the drilling fluid storage tank is provided. A drilling fluid modulator may be in fluid communication with at least one of the group consisting of the standpipe and the return line.

Abstract: The present invention provides a chemometric equation to estimate fluid density, viscosity, dielectric constant and resistivity for a formation fluid sample downhole. The chemometric estimates can be used directly as estimated values for fluid density, viscosity, dielectric constant and resistivity for a formation fluid sample downhole. The chemometric estimates can also be plugged into a Levenberg-Marquardt (LM) non-linear least squares fit, as an initial estimate of the parameter to be estimated by the LM fit. If the initial parameter estimate is too far from the actual parameter values, the LM algorithm may take a long time to converge or even fail to converge entirely. The present invention estimates an initial value of a parameter that provides a high probability that the LM algorithm will converge to a global minimum.

Abstract: A method for determining a drilling malfunction includes determining a correspondence between at least one drilling operating parameter and at least one drilling response parameter. Determining the correspondence is performed when a parameter related to a dissipative motion of the drill string falls below a selected threshold. A value of the drilling response parameter is predicted based on the correspondence and measurements of the drilling operating parameter. Existence of the malfunction is determined when the predicted value is substantially different from a measured value of the drilling response parameter.

Abstract: Measurements are made continuously with a seismic while drilling (SWD) system and the measured data are stored in a working memory of a downhole processor along with quality control (QC) measurements. The QC data are analyzed and based on the analysis, portions of the data in working memory are recorded in permanent memory for retrieval. Alternatively, QC measurements are made substantially continuously predictions are made when data quality for SWD measurements are likely to be good. Recording of SWD data are then started based on the prediction.

Abstract: A method for controlling formation pressure during the drilling of a borehole through a subterranean formation includes selectively pumping a drilling fluid through a drill string extended into a borehole, out a drill bit at the bottom end of the drill string, and into an annular space between drill string and the borehole. The drilling fluid is discharged to a reservoir to clean the drilling fluid for reuse. Annular space fluid pressure is selectively increased to maintain a selected fluid pressure proximate the bottom of the borehole by applying fluid pressure to the annular space. The selective increasing includes controlling an aperture of an orifice operatively coupled between the annular space and the reservoir. Fluid from the annular space is discharged other than through the orifice when the annular space fluid pressure exceeds a selected value, or drops below a selected value.

Abstract: An oscillating shear valve system for generating pressure fluctuations in a flowing drilling fluid comprising a stationary stator and an oscillating rotor, both with axial flow passages. The rotor oscillates in close proximity to the stator, at least partially blocking the flow through the stator and generating oscillating pressure pulses. The rotor passes through two zero speed positions during each cycle, facilitating rapid changes in signal phase, frequency, and/or amplitude facilitating enhanced, multivalent data encoding. The rotor is driven by a motorized gear drive. In one embodiment, a torsional spring is attached to the motor and the resulting spring mass system is designed to be near resonance at the desired pulse frequency. The system enables the use of multivalent encoding schemes for increasing data rates.

Abstract: A closed-loop circulating system for drilling wells has control of the flow rates in and out of the wellbore. Kicks and fluid losses are quickly controlled by adjusting the backpressure. Kick tolerance and tripping margins are eliminated by real-time determination of pore and fracture pressure. The system can incorporate a rotating BOP and can be used with underbalanced drilling.

Abstract: This application relates to various methods and apparatus for rapidly obtaining accurate formation property data from a drilled earthen borehole. Once obtained, the formation property data, including formation fluid pressure, may be corrected, calibrated and supplemented using various other data and techniques disclosed herein. Furthermore, the formation property data may be used for numerous other purposes. For example, the data may be used to correct or supplement other information gathered from the borehole; it may be used to supplement formation images or models; or, it may be used to adjust a drilling or producing parameter. Various other uses of accurately and quickly obtained formation property data are also disclosed.

Abstract: A method of controlling a well experiencing gas kicks, which includes the step of increasing pressure above maximum allowable casing pressure to offset decreases in circulating pressure. The method includes calculating a difference between initial circulating pressure and present circulating pressure to arrive at a net loss in circulating pressure. Pressure is increased above maximum allowable casing pressure by an amount approximating the net loss in circulating pressure.

Abstract: A method for communicating with a downhole tool located in a subterranean borehole is disclosed. Exemplary embodiments of the method include encoding data and/or commands in a sequence of varying drill string rotation rates and drilling fluid flow rates. The varying rotation rates and flow rates are measured downhole and processed to decode the data and/or the commands. In one exemplary embodiment, commands in the form of relative changes to current steering tool offset and tool face settings are encoded and transmitted downhole. Such commands may then be executed, for example, to change the steering tool settings and thus the direction of drilling. Exemplary embodiments of this invention advantageously provide for quick and accurate communication with a downhole tool.

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.