Patents by Inventor Larry L. Grigar

Larry L. Grigar 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).

  • Patent number: 8151882
    Abstract: A system that is usable with a well includes tubular body, at least one perforating charge that is disposed on the tubular body and at least one screen section that is disposed on the tubular body. The perforating charge(s) and the screen sectional(s) are adapted to be run downhole in a single trip into the well with the tubular body.
    Type: Grant
    Filed: September 1, 2005
    Date of Patent: April 10, 2012
    Assignee: Schlumberger Technology Corporation
    Inventors: Larry L. Grigar, Joe C. Hromas
  • Patent number: 6719061
    Abstract: Well surface equipment is provided to seal around the outer surface of portions of tool sections as the tool sections are assembled or disconnected in a portion of the well surface equipment. The portion of the well surface equipment is isolated from wellhead pressure to enhance well operator control during assembly or disassembly of a tool string. Also, if a fluid path is opened up due to activation of the tool string (such as initiation of a detonating cord that is placed in the fluid path), a barrier mechanism is actuated to block fluid communication through this fluid path so that a portion of the well surface equipment can remain isolated from wellhead pressure to enable convenient retrieval and disconnection of tool sections.
    Type: Grant
    Filed: June 7, 2002
    Date of Patent: April 13, 2004
    Assignee: Schlumberger Technology Corporation
    Inventors: Laurent E. Muller, Larry L. Grigar, Steven W. Henderson, Klaus B. Huber, Bennie C. Gill, Rolf Ludolf, Gary L. Rytlewski
  • Publication number: 20020185276
    Abstract: Well surface equipment is provided to seal around the outer surface of portions of tool sections as the tool sections are assembled or disconnected in a portion of the well surface equipment. The portion of the well surface equipment is isolated from wellhead pressure to enhance well operator control during assembly or disassembly of a tool string. Also, if a fluid path is opened up due to activation of the tool string (such as initiation of a detonating cord that is placed in the fluid path), a barrier mechanism is actuated to block fluid communication through this fluid path so that a portion of the well surface equipment can remain isolated from wellhead pressure to enable convenient retrieval and disconnection of tool sections.
    Type: Application
    Filed: June 7, 2002
    Publication date: December 12, 2002
    Inventors: Laurent E. Muller, Larry L. Grigar, Steven W. Henderson, Klaus B. Huber, Bennie C. Gill, Rolf Ludolf, Gary L. Rytlewski
  • Patent number: 5211714
    Abstract: A perforating gun assembly is set forth. It incorporates a swivel connected with a cable head assembly and a navigation system for determining the instantaneous angle of the tool with respect to a vertical reference. There are first and second spaced cages formed of sleeves supported on bearing assemblies. The sleeves support free wheeling rollers which engage the casing when the tool is in the slant hole region of the well. There is an eccentric which falls downwardly, i.e., pointing toward gravity, and thereby defines a vertical reference and hence a horizontal reference. This eccentric mounts an elongate tubular housing for the shaped charges. Initially, the angle of firing of the shaped charges is adjusted at the time of installation with respect to the horizon and that in turn is correlated to the formation of interest in the well borehole which is then perforated with perforations which are parallel to the formation bedding plane.
    Type: Grant
    Filed: September 13, 1990
    Date of Patent: May 18, 1993
    Assignee: Halliburton Logging Services, Inc.
    Inventors: John W. Jordan, Gregory N. Gilbert, Martin L. Tomek, Larry L. Grigar, Terry L. Slagle
  • Patent number: 5040619
    Abstract: A perforating gun assembly is set forth. It incorporates a swivel connected with a cable head assembly and a navigation system for determining the instantaneous angle of the tool with respect to a vertical reference. There are first and second spaced cages formed of sleeves supported on bearing assemblies. The sleeves support free wheeling rollers which engage the casing when the tool is in the slant hole region of the well. There is an eccentric which falls downwardly, i.e., pointing toward gravity, and thereby defines a vertical reference and hence a horizontal reference. This eccentric mounts an elongate tubular housing for the shaped charges. Initially, the angle of firing of the shaped charges is adjusted at the time of installation with respect to the horizon and that in turn is correlated to the formation of interest in the well borehole which is then perforated with perforations which are parallel to the formation bedding plane.
    Type: Grant
    Filed: April 12, 1990
    Date of Patent: August 20, 1991
    Assignee: Halliburton Logging Services, Inc.
    Inventors: John W. Jordan, Gregory N. Gilbert, Martin L. Tomek, Larry L. Grigar, Terry L. Slagle
  • Patent number: 4762067
    Abstract: For use in a perforating gun assembly, a perforating gun detonator is disclosed. One embodiment is hermetically sealed while the other has openings therein to admit well fluids. In both embodiments, a narrow conductive metal foil is provided with a current to vaporize the narrow foil, explode the foil and propel a flyer driven by a shock wave for detonation of a spaced secondary explosive. The explosive then couples explosion into a detonating cord against a shoulder in a housing adjacent to the secondary explosive. The current is formed by means of an AC voltage multiplier circuit providing a charge on a capacitor which is discharged through a spark gap. Charging circuitry includes a blocking capacitor to prevent DC and a resistor for bleeding a small current from the capacitor to ground which prevents static or stray current accumulation.
    Type: Grant
    Filed: November 13, 1987
    Date of Patent: August 9, 1988
    Assignee: Halliburton Company
    Inventors: James M. Barker, Larry L. Grigar, Dennis E. Schramek, Starlin M. Reid, Cyril R. Sumner
  • Patent number: 4759291
    Abstract: In an exposed perforating gun assembly, contact with well fluids at high pressure and temperature is detrimental to explosives in the explosive train. This device protects such explosives and includes a cylindrical housing with a bore having an electrical feedthrough at one end, an enclosed initiator, a cooperative sleeve and cooperative sealed retainer. The detonating cord is sealed into proximity with the initiator and is held against high pressure extrusion by the sealed retainer.
    Type: Grant
    Filed: July 6, 1987
    Date of Patent: July 26, 1988
    Assignee: Halliburton Company
    Inventors: James M. Barker, Larry L. Grigar, Dennis E. Schramek
  • Patent number: 4678044
    Abstract: In a tubing conveyed perforating gun assembly having shaped charges to perforate a well, an improved pressure sequence shaped charge detonator is included. The preferred form of device is appended to the bottom of the assembly to function as a backup detonator. First and second piston and cylinder assemblies in an elongate body provide pressure initiated arming and subsequent pressure initiated firing pin movement to achieve primer cord detonation for perforation of the well. The pressure sequence is controllable, selectively to a specified pressure to arm and thereafter to fire.
    Type: Grant
    Filed: March 31, 1986
    Date of Patent: July 7, 1987
    Assignee: Halliburton Company
    Inventors: Robert R. Luke, James M. Barker, Michael L. Smith, Larry L. Grigar, Carl B. Miller
  • Patent number: 4664184
    Abstract: In tubing conveyed perforating well completion operations, shaped charge detonation is achieved by dropping a detonating bar in the tubing string. Velocity of the detonating bar is controlled by placing a column of standing fluid above the tubing conveyed perforating assembly. This apparatus and method isolate a column of standing fluid. Moreover, invasion by a well fluid is prevented to assure that the retardation characteristics of the standing fluid are not changed by invading well fluids. The apparatus includes a tubing string pressure isolation piston assembly slidable within a sleeve and a frangible closure disk broken by the detonating bar; the isolation tool further includes check valve means controllably venting fluid pressure across the valve means.
    Type: Grant
    Filed: March 31, 1986
    Date of Patent: May 12, 1987
    Assignee: Halliburton Company
    Inventor: Larry L. Grigar
  • Patent number: 4629001
    Abstract: In a tubing conveyed perforating gun assembly having shaped charges to perforate a well, an improved pressure sequence shaped charge detonator is included. The preferred form of device is appended to the bottom of the assembly to function as a backup detonator. First and second piston and cylinder assemblies in an elongate body provide pressure initiated arming and subsequent pressure initiated firing pin movement to achieve primer cord detonation for perforation of the well. The pressure sequence is controllable, selectively to a specified pressure to arm and thereafter to fire.
    Type: Grant
    Filed: May 28, 1985
    Date of Patent: December 16, 1986
    Assignee: Halliburton Company
    Inventors: Carl B. Miller, Robert R. Luke, Michael L. Smith, Larry L. Grigar
  • Patent number: 4574892
    Abstract: For use with a tubing conveyed perforating gun assembly, a wireline manipulated electrically actuated detonator assembly traversing the interior of the tubing is described. In the preferred and illustrated embodiment, a wireline connected with a sinker bar supports the detonator assembly having a sinker bar sub terminating in a taper adjacent to a set of deflectable collet fingers comprising a latch assembly. The collet fingers are deflected outwardly by the tapered surface and are forced into an undercut located above a booster and detonating cord affixed to the tubing conveyed perforating gun assembly for firing the perforating guns.
    Type: Grant
    Filed: October 24, 1984
    Date of Patent: March 11, 1986
    Assignee: Halliburton Company
    Inventors: Larry L. Grigar, Carl B. Miller