Patents by Inventor Go Fujisawa

Go Fujisawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20110023587
    Abstract: Vibrating wire viscometers are described. Some example vibrating wire viscometer housings include a flowline through the housing to expose a first wire to a downhole fluid, a cavity in the housing to hold a magnet and to conduct one or more additional wires from the flowline to a signal generator, first and second electrically conductive posts mechanically coupled to the housing to hold the first wire in tension within the flowline, and a seal mechanically coupled to the housing to prevent access to the magnet by the downhole fluid.
    Type: Application
    Filed: August 2, 2009
    Publication date: February 3, 2011
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: RAGHU MADHAVAN, YU HATORI, MAMI NISHIDA, SOPHIE NAZIK GODEFROY, MICHAEL STANGELAND, GO FUJISAWA
  • Patent number: 7849736
    Abstract: A method and a tool that implements a method which includes measuring the viscosity and flow rates of formation fluids and obtaining the ratio of relative permeabilities of the formation fluids and wettability of the formation using the same.
    Type: Grant
    Filed: December 21, 2007
    Date of Patent: December 14, 2010
    Assignee: Schlumberger Technology Corporation
    Inventors: Maki Ikeda, Sophie Nazik Godefroy, Go Fujisawa
  • Publication number: 20100206063
    Abstract: Methods and apparatus to use multiple sensors to measure downhole fluid properties are described. An example method of measuring a property of a downhole fluid involves obtaining a plurality of measurements for each of a plurality of sensors. Each of the measurements corresponds to a same property of the downhole fluid, and each of the sensors is differently configured to measure the property. Additionally, the example method involves obtaining a plurality of weighting values, each of which corresponds to one of the sensors. The example method also involves applying the weighting values to the respective measurements obtained by each of the corresponding sensors to generate a weight-corrected measurement for each of the sensors. Further still, the example method involves generating a value representative of a measurement of the property of the downhole fluid based on the weight-corrected measurements and outputting the value representative of the measurement of the property.
    Type: Application
    Filed: February 16, 2009
    Publication date: August 19, 2010
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: GO FUJISAWA, SOPHIE NAZIK GODEFROY
  • Publication number: 20100124313
    Abstract: Example methods and apparatus to perform downhole x-ray fluorescence to detect sulfur in formation fluids are disclosed. A disclosed example downhole x-ray fluorescence apparatus comprises a flowline comprising a flowline wall, an x-ray source, a boron carbide crystal window in the flowline wall to allow x-rays emitted by the x-ray source to pass into a formation fluid in the flowline, and a detector to measure a value representative of a fluorescence of the formation fluid in response to the emitted x-rays.
    Type: Application
    Filed: November 16, 2008
    Publication date: May 20, 2010
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventor: GO FUJISAWA
  • Publication number: 20100050761
    Abstract: A gas separation and detection tool for performing in situ analysis of borehole fluid is described. A separation system such as a membrane is employed to separate one or more target gasses from the borehole fluid. The separated gas may be detected by reaction with another material or spectroscopy. When spectroscopy is employed, a test chamber defined by a housing is used to hold the gas undergoing test. Various techniques may be employed to protect the gas separation system from damage due to pressure differential. For example, a separation membrane may be integrated with layers that provide strength and rigidity. The integrated membrane separation may include one or more of a water impermeable layer, gas selective layer, inorganic base layer and metal support layer. The gas selective layer itself can also function as a water impermeable layer. The metal support layer enhances resistance to differential pressure. Alternatively, the chamber may be filled with a liquid or solid material.
    Type: Application
    Filed: August 26, 2008
    Publication date: March 4, 2010
    Applicant: SchlumbergerTechnology Corporation
    Inventors: Jimmy Lawrence, Timothy G.J. Jones, Kentaro Indo, Tsutomu Yamate, Noriyuki Matsumoto, Michael Toribio, Hidetoshi Yoshiuchi, Andrew Meredith, Nathan S. Lawrence, Li Jiang, Go Fujisawa, Oliver C. Mullins
  • Publication number: 20090159260
    Abstract: A method and a tool that implements a method which includes measuring the viscosity and flow rates of formation fluids and obtaining the ratio of relative permeabilities of the formation fluids and wettability of the formation using the same.
    Type: Application
    Filed: December 21, 2007
    Publication date: June 25, 2009
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: MAKI IKEDA, SOPHIE NAZIK GODEFROY, GO FUJISAWA
  • Publication number: 20090143992
    Abstract: Methods and apparatus to determine a concentration of nitrogen in a downhole fluid are described. An example apparatus to determine a concentration of nitrogen in a downhole fluid includes a fluid measurement unit to measure a first fluid composition and a density of at least a hydrocarbon and carbon dioxide in a sample of the downhole fluid. Additionally, the example apparatus includes one or more sensors to measure at least a pressure and a temperature of the sample. Further, the example apparatus includes a processing unit to determine a first theoretical density based on at least the first fluid composition, the temperature, and the pressure the sample. Further still, the example apparatus includes an analyzer to determine a first difference between the density of at least the hydrocarbon and the carbon dioxide in the sample and the first theoretical density. The first difference is associated with a concentration of nitrogen in the sample.
    Type: Application
    Filed: November 24, 2008
    Publication date: June 4, 2009
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: GO FUJISAWA, CHEE KIN KHONG, OLIVER C. MULLINS
  • Patent number: 7500388
    Abstract: A wireline-conveyed side-wall core coring tool for acquiring side-wall core from a geological formation for performing in-situ side-wall core analysis. The coring tool has a core analysis unit operable to measure geophysical properties of an acquired side-wall core. The measured geophysical properties may be used to determine the success of the acquisition of side-wall cores by the coring tool. The core analysis unit is operable of performing an in-situ interpretation of measured geophysical property of the side-wall core and transmitting in near real-time the measurements or the interpretation results to surface data acquisition and processing apparatus.
    Type: Grant
    Filed: December 15, 2005
    Date of Patent: March 10, 2009
    Assignee: Schlumberger Technology Corporation
    Inventors: Go Fujisawa, Oliver C. Mullins, Peter David Wraight, Joel Lee Groves, Lennox Reid, Felix Chen, Gary Corris, Yi-Qiao Song
  • Patent number: 7458258
    Abstract: A method for determining properties of a formation fluid is provided and includes: obtaining fluid data related to Carbon-Hydrogen molecular bonds in C6+ from a fluid analyzer; and considering the fluid data to calculate mass fractions of hydrocarbon flowing through the fluid analyzer. The method further includes computing gas-oil-ratio of hydrocarbon based on the mass fractions of hydrocarbon. Another method for determining a gas-oil-ratio of a formation fluid includes: obtaining fluid data related to Carbon-Hydrogen molecular bonds in C6+ from a fluid analyzer; considering the fluid data to derive mass fractions of gas and oil; and computing gas-oil-ratio of hydrocarbon based on the derived mass fractions.
    Type: Grant
    Filed: December 16, 2005
    Date of Patent: December 2, 2008
    Assignee: Schlumberger Technology Corporation
    Inventors: ChengGang Xian, Andrew Carnegie, ChengLi Dong, Oliver C. Mullins, Go Fujisawa
  • Patent number: 7336356
    Abstract: A downhole fluid analysis system comprises an input light signal that is directed through a fluid sample housed in a sample cell. The input light signal may originate from a plurality of light sources. A light signal output from the sample cell is then routed to two or more spectrometers for measurement of the represented wavelengths in the output light signal. The output of the spectrometers is then compared to known values for hydrocarbons typically encountered downhole. This provides insight into the composition of the sample fluid. Additionally, the input light can be routed directly to the two or more spectrometers to be used in calibration of the system in the high temperature and noise environment downhole.
    Type: Grant
    Filed: January 26, 2006
    Date of Patent: February 26, 2008
    Assignee: Schlumberger Technology Corporation
    Inventors: Stephane Vannuffelen, Kentaro Indo, Go Fujisawa, Toru Terabayashi, Tsutomu Yamate
  • Patent number: 7305306
    Abstract: Methods and systems are provided for downhole analysis of formation fluids by deriving fluid properties and associated uncertainty in the predicted fluid properties based on downhole data, and generating answer products of interest based on differences in the fluid properties. Measured data are used to compute levels of contamination in downhole fluids using an oil-base mud contamination monitoring (OCM) algorithm. Fluid properties are predicted for the fluids and uncertainties in predicted fluid properties are derived. A statistical framework is provided for comparing the fluids to generate, in real-time, robust answer products relating to the formation fluids and reservoirs thereof. Systematic errors in measured data are reduced or eliminated by preferred sampling procedures.
    Type: Grant
    Filed: May 19, 2005
    Date of Patent: December 4, 2007
    Assignee: Schlumberger Technology Corporation
    Inventors: Lalitha Venkataramanan, Go Fujisawa, Bhavani Raghuraman, Oliver Mullins, Andrew Carnegie, Ricardo Vasques, Chengli Dong, Kai Hsu, Michael O'Keefe, Henri-Pierre Valero
  • Publication number: 20070171412
    Abstract: A downhole fluid analysis system comprises an input light signal that is directed through a fluid sample housed in a sample cell. The input light signal may originate from a plurality of light sources. A light signal output from the sample cell is then routed to two or more spectrometers for measurement of the represented wavelengths in the output light signal. The output of the spectrometers is then compared to known values for hydrocarbons typically encountered downhole. This provides insight into the composition of the sample fluid. Additionally, the input light can be routed directly to the two or more spectrometers to be used in calibration of the system in the high temperature and noise environment downhole.
    Type: Application
    Filed: January 26, 2006
    Publication date: July 26, 2007
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Stephane Vannuffelen, Kentaro Indo, Go Fujisawa, Toru Terabayashi, Tsutomu Yamate
  • Publication number: 20070137292
    Abstract: A method for determining properties of a formation fluid is provided and includes: obtaining fluid data related to Carbon-Hydrogen molecular bonds in C6+ from a fluid analyzer; and considering the fluid data to calculate mass fractions of hydrocarbon flowing through the fluid analyzer. The method further includes computing gas-oil-ratio of hydrocarbon based on the mass fractions of hydrocarbon. Another method for determining a gas-oil-ratio of a formation fluid includes: obtaining fluid data related to Carbon-Hydrogen molecular bonds in C6+ from a fluid analyzer; considering the fluid data to derive mass fractions of gas and oil; and computing gas-oil-ratio of hydrocarbon based on the derived mass fractions.
    Type: Application
    Filed: December 16, 2005
    Publication date: June 21, 2007
    Inventors: ChengGang Xian, Andrew Carnegie, ChengLi Dong, Oliver Mullins, Go Fujisawa
  • Publication number: 20070137894
    Abstract: A wireline-conveyed side-wall core coring tool for acquiring side-wall core from a geological formation for performing in-situ side-wall core analysis. The coring tool has a core analysis unit operable to measure geophysical properties of an acquired side-wall core. The measured geophysical properties may be used to determine the success of the acquisition of side-wall cores by the coring tool. The core analysis unit is operable of performing an in-situ interpretation of measured geophysical property of the side-wall core and transmitting in near real-time the measurements or the interpretation results to surface data acquisition and processing apparatus.
    Type: Application
    Filed: December 15, 2005
    Publication date: June 21, 2007
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Go Fujisawa, Oliver Mullins, Peter Wraight, Joel Groves, Lennox Reid, Felix Chen, Gary Corris, Yi-Qiao Song
  • Publication number: 20060226699
    Abstract: Methods and apparatus for investigating a hydrocarbon bearing geological formation traversed by a borehole are disclosed. A borehole tool is used to acquire a sample of fluid in the formation. Compositional analysis of the fluid sample is conducted to provide a determination of the composition of the sample. The sample composition is then related to a model of the thermodynamic behavior of the fluid; i.e., the mass fractions of the fluid components are used as inputs to an equation of state (EOS) to predict the phase behavior of the fluid.
    Type: Application
    Filed: March 24, 2006
    Publication date: October 12, 2006
    Inventors: Soraya Betancourt, Anthony Goodwin, Go Fujisawa, Oliver Mullins, Hani Elshahawi, Julian Pop, Terizhandur Ramakrishnan, Li Jiang
  • Patent number: 7095012
    Abstract: Methods of analyzing formation fluids in an oilfield environment are near-infrared absorption spectroscopy. Indications of near-infrared absorptions are analyzed to determine the concentration of compounds in a formation fluid sample.
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: August 22, 2006
    Assignee: Schlumberger Technology Corporation
    Inventors: Go Fujisawa, Oliver C. Mullins, Toru Terabayashi, Fredrick A. Jenet, Maria A. van Agthoven, Philip A. Rabbito
  • Patent number: 7081615
    Abstract: Methods and apparatus for investigating a hydrocarbon bearing geological formation traversed by a borehole are disclosed. A borehole tool is used to acquire a sample of fluid in the formation. Compositional analysis of the fluid sample is conducted to provide a determination of the composition of the sample. The sample composition is then related to a model of the thermodynamic behavior of the fluid; i.e., the mass fractions of the fluid components are used as inputs to an equation of state (EOS) to predict the phase behavior of the fluid.
    Type: Grant
    Filed: December 3, 2002
    Date of Patent: July 25, 2006
    Assignee: Schlumberger Technology Corporation
    Inventors: Soraya S. Betancourt, Anthony Goodwin, Go Fujisawa, Oliver C. Mullins, Hani Elshahawi, Julian Pop, Terizhandur S. Ramakrishnan, Li Jiang
  • Publication number: 20060155474
    Abstract: Methods and systems are provided for downhole analysis of formation fluids by deriving fluid properties and associated uncertainty in the predicted fluid properties based on downhole data, and generating answer products of interest based on differences in the fluid properties. Measured data are used to compute levels of contamination in downhole fluids using an oil-base mud contamination monitoring (OCM) algorithm. Fluid properties are predicted for the fluids and uncertainties in predicted fluid properties are derived. A statistical framework is provided for comparing the fluids to generate, in real-time, robust answer products relating to the formation fluids and reservoirs thereof. Systematic errors in measured data are reduced or eliminated by preferred sampling procedures.
    Type: Application
    Filed: May 19, 2005
    Publication date: July 13, 2006
    Inventors: Lalitha Venkataramanan, Go Fujisawa, Bhavani Raghuraman, Oliver Mullins, Andrew Carnegie, Ricardo Vasques, Chengli Dong, Kai Hsu, Michael O'Keefe, Henri-Pierre Valero
  • Patent number: 7075063
    Abstract: The invention provides a method for determining phase transition pressure of downhole retrograde condensate. An OBM-contamination value is produced from a time-series of fluorescence values produced by measuring fluorescence emitted from a single-phase flow of OBM-contaminated formation fluid in a downhole cell during a cycle of time. The pressure of fluid in the cell is set at a transition boundary by incrementing drawdown pressure and monitoring the presence or absence of a phase transition. An apparent phase transition pressure value associated with the cycle of time is produced by setting apparent phase transition pressure value equal to cell pressure. This process is repeated for several cycles of time to produce a number of pairs of OBM-contamination value and apparent phase transition pressure value as OBM-contamination decreases over time.
    Type: Grant
    Filed: September 25, 2003
    Date of Patent: July 11, 2006
    Assignee: Schlumberger Technology Corporation
    Inventors: Chengli Dong, Soraya S. Betancourt, Go Fujisawa, Oliver C. Mullins, James J. Dunlap
  • Patent number: 7028773
    Abstract: Water-based mud filtrate concentration in a downhole fluid sample drawn from the borehole of an oil well is assessed. To measure water-based mud filtrate concentration, a water-based mud having a water-soluble fluorescent dye tracer is pumped into the borehole; sample fluid from a selected downhole location is pumped through a downhole flow line having a window; sample fluid flowing in an excitation region of the downhole flow line is illuminated through the window with fluorescence excitation light; and fluorescence emission from the excitation region is measured to produce a measured value. The measured value represents the fraction of water-based mud filtrate in the sample fluid. A calibration value is determined representing 100% water-based mud filtrate. A method for validating a sample of connate water as having an acceptably low WBM filtrate contamination tests for validation downhole, in real time.
    Type: Grant
    Filed: December 13, 2002
    Date of Patent: April 18, 2006
    Assignee: Schlumberger Technology Coporation
    Inventors: Go Fujisawa, Oliver C. Mullins, Chengli Dong, Andrew Kurkjian