Abstract: An automated batch sampling drilling mud management system includes a portable mud measurement system and a communications system. The portable mud measurement system has or more measurement devices arranged to measure at least one property and/or characteristic of drilling mud; and a pumping system arranged to pump a batch sample of drilling mud from a supply of drilling mud to the one or more measurement devices. The pumping system is also able to subsequently flush the batch sample of drilling mud from the one or more measurement devices. The communications system enables bidirectional communications between the mud management system and a remote location to enable transfer of data therebetween and the exertion of control from the remote location to the mud management system.

Abstract: A system and method for controlling a pumps configured to pump fluid from a fluid supply to a frac iron configuration. A pressure schedule is defined, the pressure schedule including a pumps assigned to sets of pumps, wherein each set of pumps is associated with a pressure level and wherein each set of pumps except a first set of pumps is a subset of a previous set of pumps. The first set of pumps is enabled to pump fluid continuously until the fluid in the manifold has reached a predetermined pressure level. A processor then automatically disables the electric pumps that are not in the next set of electric pumps, while allowing the next set of pumps to continue to pump fluid until the fluid in the manifold has reached the next pressure level. This continues until the manifold is at the desired pressure.

Abstract: A pump unit includes a pump and a metal ion trap. The pump includes a metal member that comes into contact with a mobile phase. The pump pumps a mobile phase through a flow path. The metal ion trap includes a filter element. The filter element includes a metal ion retention structure for retaining metal ions by interacting with the metal ions included in a mobile phase. The filter element is provided in the flow path for a mobile phase pumped by the pump. The pump unit may be provided in a chromatograph.

Abstract: Processes for injection of fluids into a wellbore via drill pipe. In some embodiments, the process can include positioning a downhole apparatus on a drill pipe. The process can also include placing the downhole apparatus at a desired station depth within a wellbore. The process can also include attaching a cable to the downhole apparatus from an up-hole environment. The process can also include setting at least one packer to seal a space between at least a portion of the downhole apparatus and an inner surface of the wellbore. The process can also include introducing a fluid to the downhole apparatus through the drill pipe and using a pump to inject at least a portion of the fluid into a geological stratum.

Abstract: A method is for testing the pressure integrity of a barrier in an annulus outside a pipe string in a wellbore, the method including the steps of: establishing a fluid connection between an inside of the pipe string and an annulus out-side the pipe string at a first position and second positions in the wellbore, the second position being offset from the first position along the axial direction of the wellbore; establishing a temporary barrier between the fluid connections at the first and second positions in the wellbore; establishing a pressure differential across the temporary barrier; releasing a tracer from below the temporary barrier; and sniffing for tracer above the temporary barrier to verify a leakage through the temporary barrier and/or the barrier in the annulus. There is also disclosed a tool for executing such a method.

Abstract: A device and a method for simulating layered stratum containing natural gas hydrates are provided. The device includes a reactor; wherein the reactor includes an upper cover, a lower cover, and a reactor body, wherein the upper cover and the lower cover are sealably attached to two ends of the reactor body to form a closed chamber; an overlying pressure layer, a superstratum layer, a hydrate layer and a substratum layer are sequentially formed throughout inside of the closed chamber from the upper cover to the lower cover, wherein each layer is respectively filled with different kinds of porous media and fluids and the each layer is provided with a stratal-fluid annular container; each stratal-fluid annular container has an outer periphery contacting an inner surface of the reactor body. The method is conducted using the device.

Abstract: An annulus pressure release system includes a gas metering valve assembly having a fluid pathway. The gas metering valve assembly includes a pressure sensor configured to be fluidly coupled to an annulus and to output a sensor signal indicative of a fluid pressure within the annulus. The gas metering valve assembly also includes an electronically actuated adjustable control valve disposed along the fluid pathway and a electronically actuated two-position valve disposed along the fluid pathway. Furthermore, the gas metering valve assembly includes a flow controller. The flow controller, in response to determining the fluid pressure exceeds a threshold pressure, is configured to output a first control signal to the electronically actuated two-position valve indicative of instructions to open the electronically actuated two-position valve, and to output a second control signal to the electronically actuated adjustable control valve indicative of instructions to adjust a flow of fluid through the fluid pathway.

Abstract: A method of determining a presence of stratigraphic traps includes obtaining a Gamma ray (GR) log dataset. The GR log dataset includes values for a plurality of wells in an area of interest. The method includes determining a geological time period corresponding to a depth in the GR log dataset; determining a spectrum of Earth's orbital parameters corresponding to the geological time period; determining peak frequencies of the spectrum of Earth's orbital parameters; and determining a quantity of orbital cycles per well in the area of interest. The spectrum of Earth's orbital parameters includes parameters for eccentricity, obliquity, and precession. The orbital cycles may be reflected as sedimentary patterns in a geologic record. The method includes determining a presence of stratigraphic traps, based, at least in part, on differences in quantities of orbital cycles between one or more wells in the area of interest.

Abstract: A method for monitoring and controlling a downhole pressure of a well during formation of a borehole of a well is provided. The method can include monitoring a downhole pressure of a well during formation of a borehole of the well using a millimeter wave drilling apparatus including a waveguide configured for insertion into the borehole. The monitoring can include determining the downhole pressure. The downhole pressure can include an amount of pressure present at a bottom of the well. The method can also include determining a lithostatic pressure of rock surrounding the well at the bottom of the well. The method can further include controlling the downhole pressure relative to the lithostatic pressure of the rock surrounding the well at the bottom of the well. Related systems performing the methods are also provided.

Abstract: Embodiments provide a pressure meter testing apparatus and method that allows operations/engineers the ability to determine in-situ stiffness values of geological stratum.

Abstract: A compact instrumented downhole coupling that includes a carrier and a set of sensors and electronics that are installed within the carrier. The carrier is a tubular structure having couplings at each end and a bore therethrough, where cavities are formed in the carrier wall. The cavities are open to a side facing away from the carrier's bore, where sensors placed in the cavities are accessible through the side opening. Electrical connections to the sensors are made via the side opening, and a clamp can be installed in the cavities via the side opening, the clamp holding the sensors securely in position within the cavities. After installation of the sensors in the cavities, plates are welded over the side opening to form an enclosure for the sensors in the carrier wall.

Abstract: Embodiments of the disclosure can include systems, methods, and devices for determining saturation pressure of an uncontaminated fluid. A technique facilitates fluid analysis in situ at a downhole location. Downhole saturation pressure measurements and downhole OBM filtrate contamination of a contaminated fluid may be obtained and a relationship may be determined between the saturation pressure measurements and OBM filtrate contamination. The relationship may be extrapolated to zero OBM filtrate contamination to determine the saturation pressure of the uncontaminated fluid. According to an embodiment, a sample of oil is obtained at the downhole location from oil in a reservoir. A downhole sampling system is used to determine whether a sample has contamination and other selected characteristics of the sample. The data obtained may be processed to provide a formation volume factor of the oil.

Abstract: The vertical counterforce loading device includes a concrete support member, four transfer components, four connection components, a vertical force transmission component and a load test soil layer. The concrete support member is formed by pouring and concreting below the load test soil layer. The four transfer components are divided into two groups to be symmetrically and parallelly anchored in the concrete support member. The vertical force transmission component includes a load plate, a jack, a primary beam and a secondary beam arranged in sequence from bottom to top. The load plate is installed on the load test soil layer. Two secondary beams are connected crosswise to both ends of the primary beam, where end portions of the secondary beams are respectively connected to second ends of the connection components through reinforcement components. The device can improve work efficiency, reduce construction costs and improve safety.

Abstract: Systems and methods to estimate a pore pressure of source rock include a pore pressure estimation processor, an executable, or both, and are operable to (i) calculate an estimate pore pressure based on overburden gradient data, a compaction velocity profile, hydrocarbon maturity, and an unloading velocity profile, (ii) determine a total organic content (TOC) estimate of the source rock based on a bulk density at a vertical depth measured using the density logging tool, (iii) determine a correction factor based on (a) the TOC estimate and (b) vitrinite ratio Ro data, and (iv) update the estimated pore pressure in real-time based on the correction factor.

Abstract: A method for monitoring and controlling a downhole pressure of a well during formation of a borehole of a well is provided. The method can include monitoring a downhole pressure of a well during formation of a borehole of the well using a millimeter wave drilling apparatus including a waveguide configured for insertion into the borehole. The monitoring can include determining the downhole pressure. The downhole pressure can include an amount of pressure present at a bottom of the well. The method can also include determining a lithostatic pressure of rock surrounding the well at the bottom of the well. The method can further include controlling the downhole pressure relative to the lithostatic pressure of the rock surrounding the well at the bottom of the well. Related systems performing the methods are also provided.

Abstract: A system for monitoring and controlling downhole pressure of a well borehole relative to a lithostatic pressure of rock surrounding the borehole is provided. The system can include a millimeter wave drilling apparatus including a gyrotron configured to inject millimeter wave radiation energy into a borehole of a well via a waveguide configured for insertion into the borehole. The borehole can be formed via the millimeter wave drilling apparatus and having a downhole pressure monitored at a bottom of the well. The system can also include a compressor fluidically coupled to the borehole and configured to control the downhole pressure via a gas supplied into and/or received from the borehole. The compressor can be configured to control the downhole pressure relative to a lithostatic pressure determined for rock surrounding the well at the bottom of the well.

Abstract: A mud flow measurement apparatus is described which is capable of measuring mud flow rate and density at or near the wellhead during a drilling operation. A riser assembly includes a torus wedge meter and density detection elements which are interconnected with a flow computer. Flow parameters are measured for unscreened drilling mud exiting a wellbore.

Abstract: A fluid extraction tool can include a body, a sealing pad extending from a portion of the elongated body, a container holding a selective permeability agent (SPA), and a device. The sealing pad can have an opening for establishing fluidic communication between an earth formation and the elongated body, an outer surface to hydraulically seal a region along an inner surface of a wellbore and a recess within the sealing pad establishing a fluid flow channel along the inner surface of the wellbore. The device can inject the SPA through an outlet of the body into the earth formation, and extract a formation fluid through the opening, wherein the formation fluid being collected is from the region along the inner surface of the wellbore sealed off by the sealing pad.

Abstract: An integrated hydraulic fracture design model that utilizes elastic fluids with high proppant suspension and low required power for injection into a hydrocarbon-bearing, subterranean formation. The integrated physics-based approach utilizes a hybrid friction model to compute viscous and elastic behavior to estimate pressure losses at different pumping conditions coupled with a novel geomechanical model capable of modeling proppant transport with elastic fluids in planar hydraulic fractures and natural fractures. An integrated process to optimize hydraulic fracture design evaluates and quantifies the proppant-carrying capacity of elastic fluids and its impact on the proppant transport process, and low water requirements.

Abstract: An compact instrumented downhole coupling that includes a carrier and a set of sensors and electronics that are installed within the carrier. The carrier is a tubular structure having couplings at each end and a bore extending through the carrier from the first end to the second end, forming a carrier wall between the bore and the exterior surface of the carrier. The bore and couplings are offset from a central axis of the carrier (the axis of the cylindrical outer surface of the carrier), resulting in a thicker portion of the carrier wall on one side of the carrier. Cavities are formed (e.g., by drilling holes) within the thicker portion of the carrier wall. One or more sensors and corresponding electronics are then positioned within the cavities, so that the carrier wall itself forms a housing for the sensors and electronics.

Abstract: Apparatus and methods for determining a laminar-turbulent transition of a fluid are provided. For example, a measurement tool can receive a set of wellbore conditions received from a wellbore. Measurement tool parameters can be determined based on the set of wellbore conditions. The measurement tool can be set according to the measurement tool parameters such that a fluid received from the wellbore can move through the measurement tool in a laminar state. The measurement tool may be adjusted according to the measurement tool parameters such that the fluid moves in a turbulent state. The measurement tool may determine a laminar-turbulent transition region for the fluid. The measurement tool may output the laminar-turbulent transition region for use in a drilling operation in the wellbore.

Abstract: A system for measuring the depth and location of a buried pipeline includes a probe having a GPS receiver, an elevation sensor, and a removable tablet computer for capturing data corresponding to the position and elevation of an underground pipeline and the corresponding soil surface covering the pipeline. Collected data is aggregated at a central computer which produces topographical maps of the pipeline's current relationship to the soil and calculates a desired soil covering. The calculated amount and placement of soil to achieve a desired end topography is used in abatement of any soil erosion or compaction. In alternative embodiments the required soil for abatement is transmitted to earth moving equipment.

Abstract: A shunt current regulator can be used to maintain current levels at downhole device on a tubing encapsulated cable and improve communication speed between the surface and downhole devices. The shunt current regulator reduces the current noise on the tubing encapsulated cable allowing for higher bitrate transfer. In some aspects, a sensing element monitors the current drawn and generates a sense signal. In other aspects, a compensation signal is generated from the sense signal. The compensation signal may be used as input to control a transistor to regulate the current drawn from the tubing encapsulated cable. The transistor can dissipate power to stabilize the current drawn or provide compensation current to increase the current drawn.

Abstract: A hydraulic pumping method for use with a subterranean well can include mounting a hydraulic actuator above a wellhead, the hydraulic actuator and the wellhead being axially aligned with each other and inclined relative to vertical The hydraulic actuator can be unsupported by any substructure or guy wires after the mounting. A hydraulic pumping system for use with a subterranean well can include a hydraulic actuator including a piston that displaces in response to pressure in the actuator, a magnet that displaces with the piston, and a magnetic field sensor that detects a presence of the magnet. The hydraulic actuator may be mounted above a wellhead, with the hydraulic actuator and the wellhead being axially aligned with each other and inclined relative to vertical.

Abstract: Methods and apparatus to calibrate micro-electromechanical systems are disclosed. An example pressure sensor calibration apparatus includes a mechanical lift to move a pressure sensor between a first height, a second height, and a third height; one or more sensors to measure first pressure and capacitance values at the first height, second pressure and capacitance values at the second height, and third pressure and capacitance values obtained at the third height; and a calibrator to determine calibration coefficient values to calibrate the pressure sensor based on the first pressure and capacitance values obtained at the first height, the second pressure and capacitance values at the second height, and the third pressure and capacitance values obtained at the third height.

Abstract: A sensor assembly includes a first sensor and a second sensor. An enclosure is operably coupled to each of the first and second sensors and contains memory that stores compensation data for each of the first and second sensors. A connector is operably coupled to the first and second sensors. A bioreaction sensing assembly as well as a method of manufacturing the bioreaction sensing assembly is also provided.

Abstract: A system and method of monitoring a pressure, temperature, and/or vibration of a hostile environment without requiring the use of active electronics or an oscillator circuit in that environment. The system and method interrogate a resonant pressure sensor and a resonant or passive temperature sensor connected to a transmission line and located at least 100 feet (30.48 m) away from a network analyzer. The system and method use the reflected frequencies from the sensors to determine the pressure, temperature, and/or vibration. If the sensors are networked by the transmission line or a network filter, the reflected portion can include the reflected transmission energy. The applied signal and reflected portion travel along the transmission line, which is preferably impedance matched to that of the system. If a multi-conductor cable is used, the effects of the cable's length and temperature are compensated for via a system calibration when in field use.

Abstract: A method of testing an earth formation can include incrementally opening a choke while drilling into the formation is ceased, thereby reducing pressure in a wellbore, and detecting an influx into the wellbore due to the reducing pressure in the wellbore. Another method of testing an earth formation can include drilling into the formation, with an annulus between a drill string and a wellbore being pressure isolated from atmosphere, then incrementally opening a choke while drilling is ceased, thereby reducing pressure in the wellbore, detecting an influx into the wellbore due to the reducing pressure in the wellbore, and determining approximate formation pore pressure as pressure in the wellbore when the influx is detected. Drilling fluid may or may not flow through the drill string when the influx is detected. A downhole pressure sensor can be used to verify pressure in the wellbore.

Abstract: The disclosure provides a sensor cartridge that includes a protective housing that is resistant to downhole oilfield environment; a sensor within the protective housing able to measure a parameter of the down-hole oilfield environment; an attaching device to interconnect with another sensor cartridge and/or a hub; a data communication unit within the protective housing, the data communication unit providing wireless communication of the measured parameter to the other sensor cartridge and/or the hub when interconnected with the other sensor cartridge and/or the hub; and a power unit within the protective housing, the power unit providing power supply to sensor and/or data communication unit.

Abstract: A component of the hydrocarbon well system and a first supply line to the component can be isolated from other components of the hydrocarbon well system. The component and the first supply line can be pressurized to a test pressure with a test fluid. Then, a pressure and a temperature of the test fluid in the component that was pressurized can be measured over a period of time. The pressure and the temperature that were measured can be analyzed and a pressure integrity of the component can be determined based on the analysis.

Abstract: A system and method for determining at least one fluid characteristic of a downhole fluid sample using a downhole tool are provided. In one example, the method includes performing a calibration process that correlates optical and density sensor measurements of a fluid sample in a downhole tool at a plurality of pressures. The calibration process is performed while the fluid sample is not being agitated. At least one unknown value of a density calculation is determined based on the correlated optical sensor measurements and density sensor measurements. A second optical sensor measurement of the fluid sample is obtained while the fluid sample is being agitated. A density of the fluid sample is calculated based on the second optical sensor measurement and the at least one unknown value.

Abstract: A system for making temperature and pressure measurements distributed over a distance comprises a plurality of Bragg grating measurement points disposed in an optical fiber with a predetermined spacing between adjacent Bragg grating measurement points and a substrate with the optical fiber disposed thereon, at least a portion of the optical fiber being wrapped around the substrate with at least one predetermined wrap angle, wherein the predetermined wrap angle and predetermined spacing are selected to enable a temperature measurement signal to be distinguished from a bending measurement signal, wherein the substrate has a first coefficient of thermal expansion greater than a second coefficient of thermal expansion of the optical fiber and wherein the substrate comprises a hollow tube portion and a solid rod portion, each having optical fiber disposed thereon.

Abstract: The invention relates to a method and an apparatus for detecting tightness of threaded joints of drill rods when unfastening at least one threaded joint of the drilling equipment (6) by impacting the drilling equipment (6) with a percussion device in the rock drilling rig (1). For detecting the tightness there is predetermined at least one fastened model for a situation where the threaded joint/joints are fastened, a vibration signal measured during impacting is compared with both the fastened model and the unfastened model and, on the basis of the comparison, it is determined to which one of the models the tightness of the threaded joints better corresponds at the moment of determination.

Abstract: Methods for making and systems employing pressure and temperature sensors are described. Embodiments include a capacitive element including a first conductor plate and a second conductor plate. Each plate includes a conductor layer formed on a substrate. In a pressure sensor embodiment, seal is positioned at or near the edges of the conductor plates, and a gas retained in a gap defined between the plates. In a temperature sensor embodiment, the gap defined between the plates is in fluid communication with the external environment.

Abstract: A downhole load cell calibrated for enhanced accuracy. The load cell may be a dry load cell calibrated by storage of pre-determined temperature and pressure data relative to the load cell based on known loads applied thereto. Thus, surface equipment employed with the load cell may include a computer program that takes advantage of the stored pre-determined information. The computer program may then be employed for calibration of downhole load cell data based on readings from the load cell along with downhole temperature and pressure information.

Abstract: The invention concerns an independent measuring and processing probe designed to be lowered in a tube for temporarily installation at the bottom of a hydrocarbon well. It includes removable anchoring resources (3, 4) capable of anchoring the probe to a casing at the bottom of the well, a set of sensors, at least one of which is a seismic sensor, recording resources, resources for processing the measurements provided by the sensors, and a central body (1) integrally reamed throughout the whole of its length by an opening (2) so as to allow free passage through the probe when it is in the anchored position. Such a probe can be used in particular to effect a reliable preliminary study on the well before installing a more complete observation system.

Abstract: A method of TI formation evaluation is disclosed. The method comprises receiving a plurality of borehole measurements; deriving a correlation between a first TI stiffness parameter and other TI stiffness parameters where the first and other TI stiffness parameters representing mechanical behavior of the TI formation; and computing the first and other TI stiffness parameters based on the borehole measurements and the derived correlation. The method further comprises evaluating TI formation elastic properties based on the computed first and other TI stiffness parameters. The method further comprises assuming that the shear modulus parallel to TI symmetric axis can be approximated from other moduli.

Abstract: It is shown that a pressure pulse originating in a well is correlated to a pulse observed at a distant well with a characteristic time. The correlation time is directly related to the diffusion time scale arising out of the pressure diffusion equation. The relationship is affected by the source-observer or observer-observer distance but the correction is small for large distances. In practice, further corrections have to be included for finite width pulses. For these pulses, a practical scheme for continuous permeability monitoring is presented.

Abstract: Methods and apparatuses are disclosed for measuring and controlling liquid levels in a well. The apparatus may include a plurality of sensors, the plurality of sensors comprising: a first sensor coupled to the well, the first sensor configured to measure a casing pressure, a second sensor coupled to the well, the second sensor configured to measure a tubing pressure, and a third sensor coupled to a motor that is further coupled to the well, the third sensor configured to measure at least one characteristic of the motor, and a processor coupled to the plurality of sensors, wherein the processor calculates a level of liquid in the well based upon measurements of at least two of the plurality of sensors.

Abstract: The present invention provides an apparatus and method for continuously monitoring the integrity of a pressurized well bore fluid sample collected downhole in an earth boring or well bore. The CDR continuous by measures the temperature and pressure for the down hole sample. Near infrared, mid infrared and visible light analysis is also performed on the small amount of sample to provide an on site analysis of sample properties and contamination level. The onsite analysis comprises determination of gas oil ratio, API gravity and various other parameters which can be estimated by a trained neural network or chemometric equation a flexural mechanical resonator is also provided to measure fluid density and viscosity from which additional parameters can be estimated by a trained neural network or chemometric equation. The sample tank is overpressured or supercharged to obviate adverse pressure drop or other effects of diverting a small sample to the CDR.

Abstract: A sensor for measuring at least one of temperature and pressure in a borehole, the sensor including a mixing medium disposed in a housing adapted for insertion into the borehole, the mixing medium exposed to at least one of the temperature and the pressure; wherein the mixing medium is used for four wave mixing of light to provide a signal that indicates at least one of the temperature and the pressure.

Abstract: Methods for making and systems employing pressure and temperature sensors are described. Embodiments include a capacitive element including a first conductor plate and a second conductor plate. Each plate includes a conductor layer formed on a substrate. In a pressure sensor embodiment, seal is positioned at or near the edges of the conductor plates, and a gas retained in a gap defined between the plates. In a temperature sensor embodiment, the gap defined between the plates is in fluid communication with the external environment.

Abstract: Fluid column weight correction using discrete point and fiber optic temperature measurement. A method for determining pressure at a distal end of a fluid column in a well includes the steps of: dividing the fluid column into multiple segments; determining a temperature of each segment; and determining a pressure and density for each segment. Another method includes the steps of: determining the temperature of each segment by measuring a temperature in the well near a proximal end of the fluid column, and using the measured temperature in conjunction with a thermal wellbore model to generate a temperature profile of the fluid column. Another method includes the steps of: causing a pressure change in the fluid column; recording multiple pressure measurements during the pressure change; and generating a temperature profile of the fluid column for each of the pressure measurements.

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: An apparatus and method for determining at least one downhole formation property is disclosed. The apparatus includes a probe and a pretest piston positionable in fluid communication with the formation, and a series of flowlines pressure gauges, and valves configured to selectively draw into the apparatus for measurement of one of formation fluid and mud; The method includes performing a first pretest to determine an estimated formation parameter; using the first pretest to design a second pretest and generate refined formation parameters whereby formation properties may be estimated.

Abstract: A while drilling system and method for determining annular pressure while drilling is provided. The system is positioned in a drilling tool suspended from a drilling rig via a drill string. The system includes at least one drill collar, a while drilling tool and at least one external sensor. The drill collar has a tubular sidewall defining a passage therein for the flow of drilling mud therethrough. The while drilling tool is supported in the passage of the at least one drill collar and selectively retrievable therefrom. The external sensor is positioned in the sidewall of the drill collar and isolated from the passage. The sensor is exposed to the wellbore for measurement thereof and adapted to wirelessly communicate with the while drilling tool. The system is preferably adapted for use in high temperature and pressure environments.

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 for determining the maximum and minimum horizontal stresses of formations surrounding a borehole includes the following steps: suspending a logging device in the borehole; transmitting sonic energy from the logging device to establish flexural waves in the formations; receiving, at the logging device, sonic energy from the flexural waves, and producing, from the received sonic energy, measurement signals at a number of frequencies; determining, at the number of frequencies, the fast and slow flexural wave velocities in the formations, to obtain fast and slow flexural velocity dispersions; establishing a model of formation stresses in which stresses of a loaded state are represented by the sum of an omnidirectional hydrostatically loaded mean reference stress, a vertical stress perturbation, and maximum and minimum horizontal stress perturbations; establishing an inversion model that includes inputs from the fast and slow flexural velocity dispersions and also includes unknown horizontal perturbations

Abstract: A flexible membrane for use in test cells includes instrumentation within the thickness of the membrane to accurately measure a property of a material including stresses, strains, deformation, temperature, moisture potential and moisture content of the sample. A test sample is enclosed within the membrane to isolate the specimen from testing fluids in the test chamber. The instrumentation may measure axial strains or radial strains or both.

Abstract: A method and apparatus for of determining a formation parameter of interest. The method includes placing a tool into communication with the formation to test the formation, determining a first formation characteristic during a first test portion, initiating a second test portion, the second test portion having test parameters determined at least in part by the determinations made during the first test portion, determining a second formation characteristic during the second test portion, and determining the formation parameter from one of the first formation characteristic and the second formation characteristic. The apparatus includes a draw down unit and a control system for closed loop control of the draw down unit. A microprocessor in the control system processes signals from a sensor in the draw down unit to determine formation characteristics and to determine test parameters for subsequent test portions.