Patents by Inventor Dah-Ben Liang

Dah-Ben Liang 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: 8956438
    Abstract: A cutting element for engaging earthern formations having a wear surface formed from a low coefficient of thermal expansion (CTE) composition including a polycrystalline diamond or polycrystalline cubic boron nitride hard phase material and a ductile phase low CTE material formed from an alloy made of Co, Ni, Fe, C, and Mn. The hard phase material is bonded to one another by the ductile phase material to form the low CTE composition.
    Type: Grant
    Filed: December 4, 2012
    Date of Patent: February 17, 2015
    Assignee: Smith International, Inc.
    Inventors: Zhigang Fang, Anthony Griffo, Gregory T. Lockwood, Dah-Ben Liang
  • Patent number: 8561731
    Abstract: A down hole drill bit is disclosed that includes a plurality of cutting elements mounted on a cutting structure. At least one of the plurality of cutting elements comprises a wear resistant material, the wear resistant material comprising coarse grains disposed in a binder matrix phase, wherein the binder matrix phase comprises nanoparticles uniformly dispersed therein.
    Type: Grant
    Filed: September 24, 2009
    Date of Patent: October 22, 2013
    Assignee: Smith International, Inc.
    Inventors: Madapusi K. Keshavan, Dah-Ben Liang
  • Patent number: 8323372
    Abstract: Low coefficient of thermal expansion (CTE) cermet compositions of this invention generally comprise a hard phase material and a ductile phase formed from a binder alloy, wherein the binder alloy is specially designed having a CTE that is closely matched to the hard phase material. Hard phase materials used to form low CTE compositions of this invention are selected from the group of carbides consisting of W, Ti, Mo, Nb, V, Si, Hf, Ta, and Cr carbides. The binder alloy is formed from a mixture of metals selected from the group consisting of Co, Ni, Fe, W, Mo, Ti, Ta, V, Nb, C, B, Cr, and Mn. In a preferred embodiment, low CTE compositions comprises WC as the hard phase material, and a ductile phase binder alloy formed from a mixture of Fe, Co, and Ni.
    Type: Grant
    Filed: January 31, 2000
    Date of Patent: December 4, 2012
    Assignee: Smith International, Inc.
    Inventors: Zhigang Fang, Anthony Griffo, Gregory T. Lockwood, Dah-Ben Liang
  • Patent number: 8016056
    Abstract: A cutting tool that includes at least one tungsten carbide cutting element disposed on a support, wherein at least one tungsten carbide cutting element has at least one localized region having a material property different from the remaining region, wherein the at least one localized region having a different material property is prepared by a method including determining at least one localized region needing a variation in a material property different from the remaining region; coating a portion of a surface of the at least one tungsten carbide cutting element with a refractory material such that a surface corresponding to the localized region is left uncoated; and treating the coated cutting element with a selected agent to diffuse the selected agent into the localized region is disclosed.
    Type: Grant
    Filed: June 29, 2006
    Date of Patent: September 13, 2011
    Assignee: Sandvik Intellectual Property AB
    Inventors: Ramamurthy K. Viswanadham, Dah-Ben Liang, Gregory T. Lockwood
  • Publication number: 20110168454
    Abstract: A down hole drill bit that includes a plurality of cutting elements mounted on a cutting structure, wherein at least one of the plurality of cutting elements comprises a wear resistant material, the wear resistant material comprising coarse grains disposed in a binder matrix phase, wherein the binder matrix phase comprises nanoparticles dispersed therein is disclosed.
    Type: Application
    Filed: September 24, 2009
    Publication date: July 14, 2011
    Applicant: Smith International, Inc.
    Inventors: Madapusi K. Keshavan, Dah-Ben Liang
  • Patent number: 7832506
    Abstract: Cutting elements offering increased toughness and thermal fatigue resistance can be formed of a wear resistant material having coarse grains disposed in a binder matrix with a binder content of at least about 18% by weight. The coarse grains include grains of at least one selected from the group of a transition metal carbide, a transition metal boride, and transition metal nitride. The binder content and coarse grain size may be selected to provide a Rockwell A hardness of at least about 75 Ra or a wear number of at least about 1.5.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: November 16, 2010
    Assignee: Smith International, Inc.
    Inventors: Dah-Ben Liang, Gary R. Portwood, James C. Minikus, Amardeep Singh, Jonathan Bitler
  • Patent number: 7666244
    Abstract: A hardfacing composition for a drill bit, including a carbide phase comprising from about 50% to about 75% by weight of the hardfacing composition of a combination of 16 to 40 mesh cemented tungsten carbide and 80 to 200 mesh super dense tungsten carbide cobalt particles, wherein about 5% to about 50% by weight of the carbide phase comprises the super dense tungsten carbide cobalt particles, and a binder alloy including about 25% to about 50% by weight of the hardfacing composition.
    Type: Grant
    Filed: July 5, 2005
    Date of Patent: February 23, 2010
    Assignee: Smith International, Inc.
    Inventors: Gregory T. Lockwood, Anthony Griffo, Dah-Ben Liang, Alysia C. White
  • Patent number: 7549912
    Abstract: A method for manufacturing drill bit inserts in which the inserts are finished in a centrifugal disc finishing machine. The centrifugal disc finishing machine comprises a configured surface rotating relative to a stationary receptacle, and the inserts may be finished with a mass of materials comprising at least one of a group of media, parts, detergent, and solution. Also, a method of increasing drill bit insert performance comprising accelerating a plurality of inserts in a high-energy finishing machine, wherein the acceleration results in a generally toroidal interaction between the inserts and at least one of the group comprising media, parts, detergent, and solution.
    Type: Grant
    Filed: August 4, 2005
    Date of Patent: June 23, 2009
    Assignee: Smith International, Inc.
    Inventors: Dah-Ben Liang, Ramamurthy K. Viswanadham
  • Patent number: 7475743
    Abstract: A drill bit that includes a bit body formed from a matrix powder and at least one cutting element for engaging a formation, wherein the matrix powder included (a) stoichiometric tungsten carbide particles, (b) cemented tungsten carbide particles, and (c) cast tungsten carbide particles, and wherein after formation with the matrix powder, the bit has an erosion rate of less than 0.001 in/hr, a toughness of greater than 20 ksi(in0.5), and a transverse rupture strength of greater than 140 ksi is disclosed.
    Type: Grant
    Filed: January 30, 2006
    Date of Patent: January 13, 2009
    Assignee: Smith International, Inc.
    Inventors: Dah-Ben Liang, Anthony Griffo, Thomas W. Oldham, Gregory T. Lockwood
  • Publication number: 20080245576
    Abstract: Cutting elements offering increased toughness and thermal fatigue resistance can be formed of a wear resistant material having coarse grains disposed in a binder matrix with a binder content of at least about 18% by weight. The coarse grains include grains of at least one selected from the group of a transition metal carbide, a transition metal boride, and transition metal nitride. The binder content and coarse grain size may be selected to provide a Rockwell A hardness of at least about 75 Ra or a wear number of at least about 1.5.
    Type: Application
    Filed: March 31, 2008
    Publication date: October 9, 2008
    Applicant: SMITH INTERNATIONAL, INC.
    Inventors: Dah-Ben Liang, Gary R. Portwood, James C. Minikus, Amardeep Singh, Jonathan Bitler
  • Patent number: 7407525
    Abstract: Fracture and wear resistant cutting elements are provided. Examples include a cutting element formed of a wear resistant material having a binder composition and a coarse grain size such that the portion of the cutting element formed of the wear resistant material has a fracture toughness of at least about 18 ksi(in)0.5 and a wear number of at least about 1.8. In a particular example, the wear resistant material has a fracture toughness of at least about 20 ksi(in)0.5. A down hole cutting tool incorporating such cutting elements is also provided.
    Type: Grant
    Filed: November 4, 2003
    Date of Patent: August 5, 2008
    Assignee: Smith International, Inc.
    Inventor: Dah-Ben Liang
  • Patent number: 7258177
    Abstract: An insert for a rock bit that includes tungsten carbide particles, and a cobalt binder disposed around the particles, wherein a grain size of the tungsten carbide particles and a content of the cobalt binder are selected to provide a fracture toughness of at least about 18 ksi (in)0.5, a wear number of at least about 2, and a hardness of 85 to 87 Ra is disclosed.
    Type: Grant
    Filed: May 2, 2006
    Date of Patent: August 21, 2007
    Assignee: Smith International, Inc.
    Inventors: Dah-Ben Liang, Anthony Griffo
  • Publication number: 20070175669
    Abstract: A drill bit that includes a bit body formed from a matrix powder and at least one cutting element for engaging a formation, wherein the matrix powder included (a) stoichiometric tungsten carbide particles, (b) cemented tungsten carbide particles, and (c) cast tungsten carbide particles, and wherein after formation with the matrix powder, the bit has an erosion rate of less than 0.001 in/hr, a toughness of greater than 20 ksi(in0.5), and a transverse rupture strength of greater than 140 ksi is disclosed.
    Type: Application
    Filed: January 30, 2006
    Publication date: August 2, 2007
    Applicant: Smith International, Inc.
    Inventors: Dah-Ben Liang, Anthony Griffo, Thomas Oldham, Gregory Lockwood
  • Publication number: 20070032173
    Abstract: A method for manufacturing drill bit inserts in which the inserts are finished in a centrifugal disc finishing machine. The centrifugal disc finishing machine comprises a configured surface rotating relative to a stationary receptacle, and the inserts may be finished with a mass of materials comprising at least one of a group of media, parts, detergent, and solution. Also, a method of increasing drill bit insert performance comprising accelerating a plurality of inserts in a high-energy finishing machine, wherein the acceleration results in a generally toroidal interaction between the inserts and at least one of the group comprising media, parts, detergent, and solution.
    Type: Application
    Filed: August 4, 2005
    Publication date: February 8, 2007
    Applicant: Smith International, Inc.
    Inventors: Dah-Ben Liang, Ramamurthy Viswanadham
  • Publication number: 20070000699
    Abstract: A cutting tool that includes at least one tungsten carbide cutting element disposed on a support, wherein at least one tungsten carbide cutting element has at least one localized region having a material property different from the remaining region, wherein the at least one localized region having a different material property is prepared by a method including determining at least one localized region needing a variation in a material property different from the remaining region; coating a portion of a surface of the at least one tungsten carbide cutting element with a refractory material such that a surface corresponding to the localized region is left uncoated; and treating the coated cutting element with a selected agent to diffuse the selected agent into the localized region is disclosed.
    Type: Application
    Filed: June 29, 2006
    Publication date: January 4, 2007
    Applicant: Smith International, Inc.
    Inventors: Ramamurthy Viswanadham, Dah-Ben Liang, Gregory Lockwood
  • Publication number: 20060254828
    Abstract: An insert for a rock bit that includes tungsten carbide particles, and a cobalt binder disposed around the particles, wherein a grain size of the tungsten carbide particles and a content of the cobalt binder are selected to provide a fracture toughness of at least about 18 ksi (in)0.5, a wear number of at least about 2, and a hardness of 85 to 87 Ra is disclosed.
    Type: Application
    Filed: May 2, 2006
    Publication date: November 16, 2006
    Applicant: Smith International, Inc.
    Inventors: Dah-Ben Liang, Anthony Griffo
  • Patent number: 7128773
    Abstract: A composite material includes a double cemented carbide and a coarse grain dopant, wherein the coarse grain is added in an amount sufficient to improve wear resistance of virgin double cemented carbide. The double cemented carbide may selected from the group of carbides consisting of W, Ti, Mo, Nb, V, Hf, Ta, and Cr carbides. The coarse grain dopant may also be at least one carbide selected from the group consisting of W, Ti, Mo, Nb, V, Hf, Ta, and Cr carbides. The coarse grain carbide may be between about 5% to about 90% by weight of the total carbide in the composite. Preferably, the coarse grain carbide is about 10% to about 50% by weight of the total carbide in the composite.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: October 31, 2006
    Assignee: Smith International, Inc.
    Inventors: Dah-Ben Liang, Greg Lockwood, Anthony Griffo
  • Patent number: 7036614
    Abstract: An insert for a rock bit that includes tungsten carbide particles, and a cobalt binder disposed around the particles, wherein a grain size of the tungsten carbide particles and a content of the cobalt binder are selected to provide a fracture toughness of at least about 18 ksi (in)0.5, a wear number of at least about 2, and a hardness of 85 to 87 Ra is disclosed.
    Type: Grant
    Filed: March 25, 2003
    Date of Patent: May 2, 2006
    Assignee: Smith International, Inc.
    Inventors: Dah-Ben Liang, Anthony Griffo
  • Patent number: 7017677
    Abstract: Cutting elements having coarse grain substrates and ultra hard material layers are provided. The substrates are formed from coarse grain size particles of tungsten carbide. A method of forming such cutting elements and a drag bit incorporating such cutting elements are also provided.
    Type: Grant
    Filed: May 14, 2003
    Date of Patent: March 28, 2006
    Assignee: Smith International, Inc.
    Inventors: Madapusi K. Keshavan, Anthony Griffo, David Truax, Dah-Ben Liang
  • Publication number: 20060005662
    Abstract: A hardfacing composition for a drill bit, including a carbide phase comprising from about 50% to about 75% by weight of the hardfacing composition of a combination of 16 to 40 mesh cemented tungsten carbide and 80 to 200 mesh super dense tungsten carbide cobalt particles, wherein about 5% to about 50% by weight of the carbide phase comprises the super dense tungsten carbide cobalt particles, and a binder alloy including about 25% to about 50% by weight of the hardfacing composition.
    Type: Application
    Filed: July 5, 2005
    Publication date: January 12, 2006
    Applicant: Smith International, Inc.
    Inventors: Greg Lockwood, Anthony Griffo, Dah-Ben Liang, Alysia White