Abstract: The invention discloses an experimental system and a method for wellbore pressure testing under the coexistence of gas-kick and loss-circulation, comprising a drill string simulator, a wellbore simulator and a complex stratigraphic structure simulator communicated in sequence from top to bottom; further comprising a medium return pipeline for collecting the returning test liquid and a medium leakage module for collecting the leaking test liquid; further comprising a data acquisition system for collecting data during testing. In the present invention, the experimental system has a simple structure, and the experimental method can comprehensively cover the three stages of circulating, well shut-in and well killing during the occurrence of coexistence of gas-kick and loss-circulation, multiple groups of experiments can be conducted by changing a single variable at the same stage, thus making the experimental test results applicable to all stages of wellbore pressure control in drilling operation.

Abstract: A method for in-situ determination of a wellbore formation pressure through a layer of cement, the method includes detecting an output pressure signal from a pressure sensor disposed in a housing in the cement outside a wellbore casing; detecting a first temperature signal from a first temperature sensor disposed in the housing; and calculating a temperature compensated output pressure signal based on the output pressure signal and the first temperature signal.

Abstract: An apparatus for estimating a bubble point of a fluid in an earth formation penetrated by a borehole includes: a pump configured to pump fluid from the earth formation through an extendable probe into a volume; and a processor. The processor is configured to perform a pressure-volume test on the fluid sample. The test includes: increasing the pressure of the fluid sample above formation pressure and logging the pressure and volume of the fluid sample; calculating a reference compressibility of the fluid sample; decreasing the pressure of the fluid sample and logging the pressure and volume; calculating a compressibility of the fluid sample using the logged pressure and volume obtained from during the decreasing; comparing the calculated compressibility to a threshold; and estimating the bubble point as the current fluid sample pressure when the calculated compressibility first meets or exceeds the threshold factor.

Abstract: Systems and methods are disclosed for accurately determining a pore pressure of a subsurface formation (20) penetrated by a wellbore (40). The systems and methods provide for measuring pressure and temperature at a measuring location proximal to the wellbore for a predetermined amount of time, storing the measurements, communicating the measurements and processing the pore pressure from the pressure and temperature measurements. The measuring location may be a location in a channel (50) drilled from the wellbore into the formation.

Abstract: The present invention provides a subsea apparatus for testing a hydraulic signature which has a fluid supply, a first pressure line coupled to the fluid supply, a second pressure line coupled to the fluid supply; and a pressure recording device operatively coupled to both the first pressure line and the second pressure line. A pressure recording device is capable of storing pre-determined pressure data representative of said pressure lines. The first pressure line functions at a lower pressure than the second pressure line while a pressure recording device records data to allow comparison of actual pressure data on the first and second pressure lines with said stored data.

Abstract: The present invention provides a subsea apparatus for testing a hydraulic signature which has a fluid supply, a first pressure line coupled to the fluid supply, a second pressure line coupled to the fluid supply; and a pressure recording device operatively coupled to both the first pressure line and the second pressure line. A pressure recording device is capable of storing pre-determined pressure data representative of said pressure lines. The first pressure line functions at a lower pressure than the second pressure line while a pressure recording device records data to allow comparison of actual pressure data on the first and second pressure lines with said stored data.

Abstract: A refracture-candidate diagnostic test is an injection of compressible or slightly compressible fluid at pressures in excess of minimum in-situ stress and formation fracture pressure with pressure decline following injection test recorded to detect a fracture retaining residual width from previous stimulation treatments. The diagnostic consists of small volume injections with injection time being a small fraction of time required for compressible or slightly compressible reservoir fluid to exhibit pseudoradial flow. The fracture-injection portion of a test can be considered as occurring instantaneously. Data measurements are transformed into a constant rate equivalent pressure transformation to obtain adjusted pressures or adjusted pseudovariables which are analyzed to identify dual unit-slope before and after closure periods confirming a residual retaining width.

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: 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 downhole tool system includes a downhole tool operably positionable within a wellbore and a sensor positioned within the downhole tool. The sensor has a first mode and a second mode. In the first mode, the sensor is responsive to RF interrogation. In the second mode, the sensor is not responsive to RF interrogation. The sensor is operable to transition from the first mode to the second mode upon the occurrence of a predetermined level of erosion of the downhole tool proximate the sensor. A detector is operably positionable relative to the downhole tool and in communicative proximity to the sensor. The detector interrogates the sensor to determine whether the predetermined level of erosion has occurred.

Abstract: A downhole pressure transmitter apparatus and method of making the same. A pressure fitting can be provided in association with a tube formed into a spiral shape. One end of said tube is sealed and the other end of said tube is affixed to said pressure fitting. As the tube is exposed to a differential pressure, said tube unwinds, thereby creating a rotary motion that is proportional and linear to said differential pressure sensor, thereby providing an indication of pressure within a downhole environment.

Abstract: An apparatus for determining fluid-pressure diffusivity in a borehole (12) in a formation (10) includes an electrode (16) and a strain measuring device (18),(20) (or a particle velocity measuring device (18),(20) or a particle acceleration measuring device (18),(20)) disposed a fixed distance from the electrode (16). The electrode (16) injects an electrical current into a point on a wall of the borehole (12). The strain measuring device (18),(20) measures strain (or the particle velocity measuring device (18),(20) measuresd particle velocity or the particle acceleration measuring device (18),(20) measures particle acceleration) at the fixed distance from the point of injection of the electrical current over time. The fluid-pressure diffusivity is determined based on the measured strain (or measured particle velocity or measured particle acceleration) over time.

Abstract: A method of determining an in situ PVT property of a hydrocarbon reservoir fluid that is present in a hydrocarbon-bearing formation layer traversed by a borehole, which method involves the steps of: a) calculating along the hydrocarbon-bearing formation layer the pressure gradient; and b) determining the in situ PVT property from the pressure gradient using an empirical relation that had been obtained by fitting a curve (11) through previously obtained data points (12, 13, 14) having the measured PVT property as a function of the pressure gradient.

Abstract: Surface-mounted traffic monitoring sensors that do not require substantial disruption to traffic flow to install or maintain, and that do not substantially degrade the physical integrity of the road. Pneumatic road-tube wedges and surface-mount inductive blades detect wheel-spikes and/or inductive signatures in both fixed and portable installations, single or multi-lane roadways, and provides accurate vehicle speed, volume, occupancy, turning movement counts, weaving sections, classification, re-identification, travel-time, origin and destination, lane-keeping variation, speed-variation, angle-of-attack, and vehicle weight and load distribution. This data is useful to infrastructure planners, traffic-flow modelers, to enhance the safety of work-zone crews, law enforcement, and for real-time traffic operations, etc.

Abstract: A method and apparatus integrates differential pressure measurements and absolute pressure measurements to provide virtual absolute pressure measurements over a wide range of pressures on a single integrated scale.

Abstract: An operating well of a fluid storage reserve, includes an outer wall delimiting, with a central operating tubing of the well, an annular space in which is placed a protective sheath of an electrical link cable between a surface installation and elements arranged in the well. A device for the measurement of physical parameters includes at least one compact, removable, sealed measuring subassembly arranged in a housing in communication with the interior of the central tubing and at least one compact, sealed connecting subassembly integral with the central tubing of the well and arranged at least partially in the annular space in the vicinity of the protective sheath to be connected to the electrical link cable. The sealed measuring subassembly and the sealed connecting subassembly have plane contact surfaces, each associated with a half-transformer so as to form an inductive coupling between the measuring subassembly and the connecting subassembly.

Abstract: Subsurface wellbore conditions are measured directly in the wellbore while the fluid circulation system is not pumping. The measured values are recorded at the subsurface location and subsequently transmitted to the well surface when circulation is resumed using fluid pulse telemetry (FPT). Real-time measurements made when the fluids are circulating are transmitted real time using FPT. Axially spaced measurements are used to obtain differential values. The apparatus of the invention comprises an assembly carried by a drill string that is used to selectively isolate the area within the well that is to be evaluated. The apparatus includes an assembly having axially spaced inflatable well packers that are used to isolate an uncased section of the wellbore. The apparatus is equipped with self-contained measuring and recording equipment, a fluid receiving reservoir, circulation valving, measurement while drilling equipment, and automated controls.

Abstract: A device for sensing and recording downhole data relating to an ambient environment in a production well and a method for obtaining such downhole data utilizing the device. Further, the device is used in combination with a downhole pump, and preferably, in combination with a strainer for the downhole pump. The device is connected with the downhole pump, and particularly the strainer, such that the device and the downhole pump may be conveyed or transported within, and retrieved from, the production well together or as an integral unit.