Patents by Inventor David J. Walker

David J. Walker 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: 20020020158
    Abstract: Apparatus for separating solids from flue gas in a circulating fluidized bed (CFB) boiler comprises plural vertical, impact type particle separators made of cooling tubes located within the CFB in a plurality of staggered rows. One embodiment employs a plurality of stacked, slip fit elements having apertures which accept the cooling tubes. The slip fit elements cooperate with one another to form a collecting channel, typically U-shaped, which separates particles from flue gases conveyed across the particle separators. Shiplap joints in between the individual slip fit elements prevent gas and solids from leaking therebetween and allow for thermal expansion. Alternatively, the impact type particle separators comprise cooling tubes connected to one another to form a unitary structure. Pin studs welded to the cooling tubes and covered with a coating of refractory; ceramic tiles; metal or ceramic spray coatings; metal or ceramic castings; weld overlay; and/or shields provide erosion resistance.
    Type: Application
    Filed: May 25, 2001
    Publication date: February 21, 2002
    Inventors: David J. Walker, Sundara M. Kavidass, Mikhail Maryamchik, Felix Belin, Kiplin C. Alexander, David R. Gibbs, David E. James, Donald L. Wietzke
  • Patent number: 6322603
    Abstract: An apparatus for separating solids from flue gas in a circulating fluidized bed (CFB) boiler includes a plurality of impact type particle separators mounted vertically to a wall of the CFB. The impact type particle separators being adjacently positioned and horizontally spaced. Each impact type particle separator includes a plurality of vertically mounted cooling tubes connected to a fluid circulating system. A slip fit element surrounds the cooling tubes. A cup shaped configuration is formed by side walls and a back wall. The side walls and back wall have a plurality of separate vertically aligned segments extending along the height of the impact type particle separator. Each vertically aligned segment is connected at its ends to an adjacent segment.
    Type: Grant
    Filed: July 10, 2000
    Date of Patent: November 27, 2001
    Assignee: The Babcock & Wilcox Company
    Inventor: David J. Walker
  • Patent number: 6255983
    Abstract: Radar is used to measure not only the level of slag on molten steel but also its thickness; the measurement is used to calculate the volume of slag, and, in turn the amount of additives for slag treatment. Time-of-flight data are used to identify peaks representing the distances of the surfaces of the slag and the surface of the underlying steel. The concept is applicable to other materials of differing composition, and particularly where the underlying material is relatively more conductive than the overlying material. Degassing is more efficiently practiced by using the radar slag thickness determinations to assist in vertical placement of snorkels.
    Type: Grant
    Filed: March 6, 2000
    Date of Patent: July 3, 2001
    Assignee: USX Corp
    Inventors: Gregory A. Meszaros, Frank L. Kemeny, David J. Walker, Richard J. Zaranek, Frederick J. Mannion
  • Patent number: 6130637
    Abstract: Radar is used to measure not only the level of slag on molten steel but also its thickness; the measurement is used to calculate the volume of slag, and, in turn the amount of additives for slag treatment.
    Type: Grant
    Filed: August 18, 1998
    Date of Patent: October 10, 2000
    Assignee: USX Corporation
    Inventors: Gregory A. Meszaros, Roger Marquart, David J. Walker, John G. Estocin, Frank L. Kemeny
  • Patent number: 6095095
    Abstract: A CFB reactor or combustor having an impact type primary particle separator collects solids particles from a flow of flue gas/solids and returns the collected particles along an inclined or substantially horizontal planar floor to a bottom portion of the reactor or combustor for subsequent recirculation.
    Type: Grant
    Filed: December 7, 1998
    Date of Patent: August 1, 2000
    Assignee: The Bacock & Wilcox Company
    Inventors: Kiplin C. Alexander, Felix Belin, Mikhail Maryamchik, David J. Walker
  • Patent number: 6088990
    Abstract: A weldless connection system for U-beam particle separators is provided in which one end of each U-beam is provided with sides and a back that are separated from each other forming tabs. The tabs may be bent, or folded, about 90.degree. inward toward the channel formed by the U-beam. The back tab may be twice as long as the side tabs, and the extra half length of the tab can be folded about 180.degree. back at the back of the U-beam in a double thickness. Each tab has a hole therethrough. The double-length back tab has two holes; one hole is provided through each half. When the tabs are bent inward, the holes align. A bolt and washer placed through the aligned holes may be used to secure the tabs, and thus the U-beam, to a furnace roof structure. An alternate embodiment of the invention is provided in which only the sides of the U-beam form tabs which extend past the bottom of the U-beam.
    Type: Grant
    Filed: April 9, 1998
    Date of Patent: July 18, 2000
    Assignee: The Babcock & Wilcox Compnay
    Inventors: Michael Gold, David J. Walker, David E. James
  • Patent number: 6087659
    Abstract: An apparatus and method for inspecting a surface of a sample, particularly but not limited to a semiconductor device, using an electron beam is presented. The technique is called Secondary Electron Emission Microscopy (SEEM), and has significant advantages over both Scanning Electron Microscopy (SEM) and Low Energy Electron Microscopy (LEEM) techniques. In particular, the SEEM technique utilizes a beam of relatively high-energy primary electrons having a beam width appropriate for parallel, multi-pixel imaging. The electron energy is near a charge-stable condition to achieve faster imaging than was previously attainable with SEM, and charge neutrality unattainable with LEEM. The emitted electrons may be detected using a time delay integration detector.
    Type: Grant
    Filed: July 16, 1999
    Date of Patent: July 11, 2000
    Assignee: KLA-Tencor Corporation
    Inventors: David L. Adler, David J. Walker, Fred Babian, Travis Wolfe
  • Patent number: 6058858
    Abstract: A circulating fluidized bed (CFB) reactor or combustor having an internal impact type primary particle separator which provides for internal return of all primary collected solids to a bottom portion of the reactor or combustor for subsequent recirculation without external and internal recycle conduits. The CFB reactor enclosure or furnace is provided with plural furnace outlets. This construction permits increased furnace depths and reduced furnace widths, resulting in a compact design.
    Type: Grant
    Filed: May 29, 1998
    Date of Patent: May 9, 2000
    Assignee: The Babcock & Wilcox Company
    Inventors: Felix Belin, David E. James, David J. Walker, Kiplin C. Alexander
  • Patent number: 6044805
    Abstract: A tube wall, division wall, or wing wall section for a circulating fluidized bed boiler with improved erosion resistant characteristics has a reduced diameter tube section adjacent the refractory covered by an abrasion resistant refractory tile. The refractory tile is mounted to the reduced diameter tube section with the upper edge of the refractory tile outside of or not extending beyond a solids fall line of solids in the fluidized bed to eliminate exposed discontinuities.
    Type: Grant
    Filed: May 6, 1999
    Date of Patent: April 4, 2000
    Assignee: The Babcock & Wilcox Company
    Inventors: David J. Walker, Donald L. Wietzke
  • Patent number: 5973323
    Abstract: An apparatus and method for inspecting a surface of a sample, particularly but not limited to a semiconductor device, using an electron beam is presented. The technique is called Secondary Electron Emission Microscopy (SEEM), and has significant advantages over both Scanning Electron Microscopy (SEM) and Low Energy Electron Microscopy (LEEM) techniques. In particular, the SEEM technique utilizes a beam of relatively high-energy primary electrons having a beam width appropriate for parallel, multi-pixel imaging. The electron energy is near a charge-stable condition to achieve faster imaging than was previously attainable with SEM, and charge neutrality unattainable with LEEM.
    Type: Grant
    Filed: November 5, 1997
    Date of Patent: October 26, 1999
    Assignee: KLA-Tencor Corporation
    Inventors: David L. Adler, David J. Walker, Fred Babian, Travis Wolfe
  • Patent number: 5893340
    Abstract: A water tube wall or heat transfer surface for use in a circulating fluidized bed combustor or reactor having reduced erosion at a transition between a protective refractory material and the upper wall.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: April 13, 1999
    Assignee: The Babcock & Wilcox Company
    Inventors: Felix Belin, David J. Walker
  • Patent number: 5836257
    Abstract: A circulating fluidized bed processor has a processor enclosure at least partially defined by a front wall and a rear wall spaced away from the front wall. A bottom wall is connected between the front and rear walls and a mechanism is provided for supplying primary air through the bottom wall for fluidizing a circulating bed in the enclosure. Another mechanism is provided for recirculating the bed from a top of the enclosure back to the enclosure. One or more secondary air plenum(s) are provided in the enclosure between the front and rear walls for supplying secondary air into the fluidized bed, above the bottom wall, so that secondary air reaches deep into the enclosure. The plenum(s) are formed of a waterwall which has a plurality of openings therein to allow communication of gases and solids therethrough from one side of the waterwall to the other.
    Type: Grant
    Filed: December 3, 1996
    Date of Patent: November 17, 1998
    Assignee: McDermott Technology, Inc.
    Inventors: Felix Belin, David J. Walker
  • Patent number: 5809940
    Abstract: An improved CFB reactor or combustor arrangement has at least a first and a second group of impact type particle separators or U-beams with cooling surfaces located adjacent and immediately upstream of the second group of U-beams which serve to cool flue gas/solids flowing through the CFB before it reaches the second group of U-beams. By reducing the gas temperature in the vicinity of and entering the second group of U-beams, the U-beams can be made of less expensive materials and are thus less expensive to produce and maintain. The heat absorbed by the local cooling surfaces can be applied to heat a working fluid supplied to a turbine or other process.
    Type: Grant
    Filed: May 23, 1997
    Date of Patent: September 22, 1998
    Assignee: The Babcock & Wilcox Company
    Inventors: David E. James, David J. Walker, Felix Belin
  • Patent number: 5799593
    Abstract: A drainable discharge pan apparatus for an impact type particle separator used on circulating fluidized bed (CFB) boilers employs a plurality of funnel shaped discharge pans located at a lower end of each of the impingement members in the impact type particle separator. The funnel shaped discharge pans prevent accumulation of collected particles thereon, allowing particles collected by the impingement members to fall therethrough, while preventing bypassing of flue gas around lower ends of the impact type particle separator. The outlet ends of the funnel shaped discharge pans provide substantially the same open area for the collected particles to fall therethrough as exists within each associated impingement member.
    Type: Grant
    Filed: June 17, 1996
    Date of Patent: September 1, 1998
    Assignee: McDermott Technology, Inc.
    Inventors: Felix Belin, David J. Walker
  • Patent number: 5735105
    Abstract: A continuous solvent free gelatin encapsulation apparatus and process includes an oil roll back assembly (20) for applying a controlled amount of a food-approved lubricant to a first side of the gelatin ribbon and an applicator guide bar assembly (40) for applying a controlled amount of food-approved lubricant to a second side of the gelatin ribbon. Two opposing food-approved lubricant coated gelatin ribbons are then united in a die assembly (50) to form gelatin capsules which are then dried and recovered.
    Type: Grant
    Filed: October 2, 1995
    Date of Patent: April 7, 1998
    Assignee: R. P. Scherer Corporation
    Inventors: Norman S. Stroud, David J. Walker, Kelvin R. Garnett, Arthur J. Burnett, Anthony J. Wood
  • Patent number: 5343830
    Abstract: A CFB reactor or combustor having an internal impact type primary particle separator provides cavity means and particle return means in an upper portion of the reactor enclosure to obtain direct and internal return of all primary collected solids to a bottom portion of the reactor or combustor for subsequent recirculation without external and internal recycle conduits.
    Type: Grant
    Filed: March 25, 1993
    Date of Patent: September 6, 1994
    Assignee: The Babcock & Wilcox Company
    Inventors: Kiplin C. Alexander, Felix Belin, David E. James, David J. Walker
  • Patent number: 4992085
    Abstract: An internal particle separator having impingement members positioned within the furnace enclosure across and just upstream of the furnace exit opening. These impingement members are organized into at least two staggered rows that are positioned to fully cover the exit opening thereby allowing entrained particles to strike the impingement members and free-fall directly back into the fluidized bed to increase its density. A baffle plate is attached to the lower end region of the impingement members thereby obstructing the vertical gas passage between these members.
    Type: Grant
    Filed: January 8, 1990
    Date of Patent: February 12, 1991
    Assignee: The Babcock & Wilcox Company
    Inventors: Felix Belin, David E. James, David J. Walker
  • Patent number: 4951714
    Abstract: An apparatus for vertically supporting an internal conduit subject to temperature fluctuations comprising a conduit with shear lugs secured around its perimeter. These shear lugs rest upon a spool member surrounding the conduit that is configured to permit the thermal expansion/contraction of the supported conduit as needed. This spool member is, in turn, supported by an outer casing in a manner permitting the spool member to move or rotate independent of the casing. In this fashion, no rigid connector couples the internal conduit to the outer casing, instead a spool member provides the necessary support while being fully movable with respect to both the internal conduit and the outer casing.
    Type: Grant
    Filed: November 6, 1989
    Date of Patent: August 28, 1990
    Assignee: The Babcock & Wilcox Company
    Inventors: Roger A. Detzel, Paul S. Knoebel, David J. Walker
  • Patent number: 4938171
    Abstract: This invention pertains to a segmented insert installed within the horizontal conduit of a non-mechanical means (such as an L-valve) for controlling the external flow of particulate material recycled to a fluidized bed combustor. The segmented insert is insulated to protect the horizontal conduit and the individual segments are joined together by a combination of a collar and hinge means. This method of coupling retains the co-axial alignment of the individual segments for leak-free operations while also enabling them to move or pivot independent of each other while still being connected together. Such independent movement is necessary for stress release purposes during high temperature operation.
    Type: Grant
    Filed: December 12, 1989
    Date of Patent: July 3, 1990
    Assignee: The Babcock & Wilcox Company
    Inventors: Detzel Roger A., Paul S. Knoebel, David J. Walker
  • Patent number: 4891052
    Abstract: This invention pertains to a discharge restrictor secured to the lower end region of impingement members installed in the flue gas path of a circulating fluidized bed boiler. The discharge restrictor incorporates a pivotable baffle plate that prevents the flue gas from bypassing the impingement members yet allows the particles that are collected to gather in an adjacent storage hopper. The baffle plate is normally biased to block access to the storage hopper until a sufficient mass of particles collect on the baffle plate thereby overcoming this bias. In doing so, the plate temporarily pivots to the open position enabling the particles to advance towards the storage hopper.
    Type: Grant
    Filed: February 21, 1989
    Date of Patent: January 2, 1990
    Assignee: The Babcock & Wilcox Company
    Inventors: Felix Belin, David J. Walker