Patents by Inventor Zhigang Fang

Zhigang Fang 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: 20040040750
    Abstract: A rotary cone bit, having a functionally-engineered surface of this invention, comprises a bit body having at least one leg extending therefrom, and a cone that is rotatably disposed on the leg. The cone typically comprises a plurality of cutting elements that project outwardly therefrom. The cutting elements comprises a cermet material selected from the group consisting of refractory metal carbides, nitrides, borides, carbonitrides and mixtures thereof. A functionally-engineered material is disposed over a surface portion of at least one of the cutting elements to form a wear resistant surface thereon. The wear resistant surface has a hardness that is different than that of the underlying cutting element. The wear resistant surface is provided by forming a conformable material mixture by combining one or more powders selected from the group consisting of cermets, carbides, borides, nitrides, carbonitrides, refractory metals, Co, Fe, Ni, and combinations thereof, with an applying agent.
    Type: Application
    Filed: June 3, 2003
    Publication date: March 4, 2004
    Applicant: Smith International, Inc.
    Inventors: Anthony Griffo, Zhigang Fang, Robert Denton
  • Patent number: 6698098
    Abstract: A method of forming a drill bit structure, the method including fixing spacers to the drill bit structure. The spacers are arranged at preselected locations on an outer surface of the drill bit structure. A hardfacing material is then applied to the drill bit structure, and the spacers are removed. Holes are machined in the drill bit structure at the preselected locations, and drilling inserts are positioned in each hole. A method of forming a drill bit structure, the method including applying a hardfacing material to selected surfaces of the drill bit structure. The hardfacing material includes a perforated carbide infiltrated material and a perforated powder infiltrated material. The perforations in the powder infiltrated material correspond to the perforations in the carbide infiltrated material. Holes are machined in the drill bit structure at the locations of the perforations, and drilling inserts are positioned in each hole.
    Type: Grant
    Filed: October 10, 2001
    Date of Patent: March 2, 2004
    Assignee: Smith International, Inc.
    Inventors: Anthony Griffo, Zhigang Fang, Robert H. Slaughter, Jr.
  • Patent number: 6615935
    Abstract: Rock bits comprising wear and fracture resistant surface of this invention include a steel bit body having at least one leg extending therefrom. A steel cone is rotatably disposed on the leg. The steel cone includes a plurality of steel cutting elements that each projecting outwardly a distance therefrom. At least a portion of the cone comprises a wear resistant surface formed from a wear resistant composite material. The wear resistant composite material is made by the process of combining powders selected from the group consisting of carbides, borides, nitrides, carbonitrides, refractory metals, cermets, Co, Fe, Ni, steel, and combinations thereof, to form a material mixture. The material mixture is applied onto a designated surface of the cone, in one form or another, when the cone is in a pre-existing rigid state. Depending on the particular application, the material mixture can be applied in as a slurry to the designated surface of the cone to form a coating thereon.
    Type: Grant
    Filed: May 1, 2001
    Date of Patent: September 9, 2003
    Assignee: Smith International, Inc.
    Inventors: Zhigang Fang, Anthony Griffo, Alysia C. White, Chris Cawthorne
  • Patent number: 6607835
    Abstract: Composite constructions of this invention comprise a first structural phase formed from a hard material selected from the group consisting of cermet materials, polycrystalline diamond, polycrystalline cubic boron nitride, and mixtures thereof, and a second structural phase formed from a material that is relatively softer than that used to form the first structural phase. The material selected to form the second structural phase can be the same or different from that used to form the first structural phase. The second structural phase is positioned into contact with at least a portion of the first structural phase. The composite construction includes repeated structural units that each comprise an ordered microstructure of first and second structural phases.
    Type: Grant
    Filed: June 15, 2001
    Date of Patent: August 19, 2003
    Assignee: Smith International, Inc.
    Inventors: Zhigang Fang, Anthony Griffo, Alysia C. White
  • Patent number: 6571889
    Abstract: A rotary cone bit, having a functionally-engineered surface of this invention, comprises a bit body having at least one leg extending therefrom, and a cone that is rotatably disposed on the leg. The cone typically comprises a plurality of cutting elements that project outwardly therefrom. The cutting elements comprises a cermet material selected from the group consisting of refractory metal carbides, nitrides, borides, carbonitrides and mixtures thereof. A functionally-engineered material is disposed over a surface portion of at least one of the cutting elements to form a wear resistant surface thereon. The wear resistant surface has a hardness that is different than that of the underlying cutting element. The wear resistant surface is provided by forming a conformable material mixture by combining one or more powders selected from the group consisting of cermets, carbides, borides, nitrides, carbonitrides, refractory metals, Co, Fe, Ni, and combinations thereof, with an applying agent.
    Type: Grant
    Filed: May 1, 2001
    Date of Patent: June 3, 2003
    Assignee: Smith International, Inc.
    Inventors: Anthony Griffo, Zhigang Fang, Robert Denton
  • Publication number: 20030066391
    Abstract: A method of forming a drill bit structure, the method including fixing spacers to the drill bit structure. The spacers are arranged at preselected locations on an outer surface of the drill bit structure. A hardfacing material is then applied to the drill bit structure, and the spacers are removed. Holes are machined in the drill bit structure at the preselected locations, and drilling inserts are positioned in each hole.
    Type: Application
    Filed: October 10, 2001
    Publication date: April 10, 2003
    Inventors: Anthony Griffo, Zhigang Fang, Robert H. Slaughter
  • Patent number: 6536542
    Abstract: Seals of this invention comprise an annular elastomeric ring-shaped body having a dynamic surface disposed along a first body portion, the dynamic surface comprising at least two surface elements that project outwardly therefrom to provide multiple barriers to fluid and debris migration thereacross when placed into contact with a rock bit rotary dynamic surface. The seal dynamic surface includes a recessed portion disposed between the surface elements, and a static seal surface disposed along a second body portion. At least one of the surface elements includes a wear surface that is formed from a material that is more wear resistant than materials that are used to form a remaining portion of the seal. A preferred wear surface is one formed from a composite material comprising a fabric of nonelastomeric polymeric material that is bonded together with an elastomeric material.
    Type: Grant
    Filed: October 28, 1999
    Date of Patent: March 25, 2003
    Assignee: Smith International, Inc.
    Inventors: Zhigang Fang, Chris Cawthorne, Nephi M. Mourik, Sujian Huang
  • Publication number: 20030008160
    Abstract: In one embodiment, composite constructions of the invention are in the form of a plurality of coated fibers bundled together to produce a fibrous composite construction in the form of a rod. Each fiber has a core formed from a hard phase material, that is surrounded by a shell formed from a binder phase material. In another embodiment of the invention, monolithic sheets of the hard phase material and the binder phase material are stacked and arranged to produce a swirled composite in the form of a rod. In still another embodiment of the invention, sheets formed from coated fibers are arranged to produce a swirled composite. Inserts for use in such drilling applications as roller cone rock bits and percussion hammer bits, and shear cutters for use in such drilling applications as drag bits, that are manufactured using conventional methods from these composite constructions exhibit increased fracture toughness due to the continuous binder phase around the hard phase of the composites.
    Type: Application
    Filed: September 12, 2002
    Publication date: January 9, 2003
    Applicant: Smith International, Inc.
    Inventors: J. Albert Sue, Ghanshyam Rai, Zhigang Fang
  • Publication number: 20020194955
    Abstract: Polycrystalline diamond (PCD) carbide composites of this invention have a microstructure comprising a plurality of granules formed from PCD, polycrystalline cubic boron nitride, or mixture thereof, that are distributed within a substantially continuous second matrix region that substantially surrounds the granules and that is formed from a cermet material. In an example embodiment, the granules are polycrystalline diamond and the cermet material is cemented tungsten carbide. PCD carbide composites of this invention display improved properties of fracture toughness and chipping resistance, without substantially compromising wear resistance, when compared to conventional pure PCD materials.
    Type: Application
    Filed: September 5, 2002
    Publication date: December 26, 2002
    Applicant: Smith International, Inc.
    Inventors: Zhigang Fang, Anthony Griffo, Brian A. White, Stewart Middlemiss, Ronald K. Eyre
  • Patent number: 6478887
    Abstract: A boronized wear-resistant material that includes a boron-containing composition is disclosed. The boron-containing composition includes tungsten carbide and a compound represented by the formula W3MB3, where M is selected from the group consisting of iron, nickel, cobalt and alloys thereof. Particularly, a boride layer containing WC and W3CoB3 may be formed over a cemented tungsten carbide substrate by a suitable boronizing process. Additional compounds present in the boride layer include CoB, W2CoB2, and WB. A relatively thick and uniform boride layer may be obtained over a carbide substrate to form a wear-resistant body. Such a wear-resistant body may be used to manufacture cutting tools, drawing dies, inserts for an earth-boring bit, face seals, bearing surfaces, nozzles, and so on.
    Type: Grant
    Filed: December 16, 1998
    Date of Patent: November 12, 2002
    Assignee: Smith International, Inc.
    Inventors: J. Albert Sue, Zhigang Fang, Alysia Canson White
  • Publication number: 20020162691
    Abstract: Rock bits comprising wear and fracture resistant surface of this invention include a steel bit body having at least one leg extending therefrom. A steel cone is rotatably disposed on the leg. The steel cone includes a plurality of steel cutting elements that each projecting outwardly a distance therefrom. At least a portion of the cone comprises a wear resistant surface formed from a wear resistant composite material. The wear resistant composite material is made by the process of combining powders selected from the group consisting of carbides, borides, nitrides, carbonitrides, refractory metals, cermets, Co, Fe, Ni, steel, and combinations thereof, to form a material mixture. The material mixture is applied onto a designated surface of the cone, in one form or another, when the cone is in a pre-existing rigid state. Depending on the particular application, the material mixture can be applied in as a slurry to the designated surface of the cone to form a coating thereon.
    Type: Application
    Filed: May 1, 2001
    Publication date: November 7, 2002
    Inventors: Zhigang Fang, Anthony Griffo, Alysia C. White, Chris Cawthorne
  • Patent number: 6454027
    Abstract: Polycrystalline diamond (PCD) carbide composites of this invention have a microstructure comprising a plurality of granules formed from PCD, polycrystalline cubic boron nitride, or mixture thereof, that are distributed within a substantially continuous second matrix region that substantially surrounds the granules and that is formed from a cermet material. In an example embodiment, the granules are polycrystalline diamond and the cermet material is cemented tungsten carbide. PCD carbide composites of this invention display improved properties of fracture toughness and chipping resistance, without substantially compromising wear resistance, when compared to conventional pure PCD materials.
    Type: Grant
    Filed: March 9, 2000
    Date of Patent: September 24, 2002
    Assignee: Smith International, Inc.
    Inventors: Zhigang Fang, Anthony Griffo, Brian A. White, Stewart Middlemiss, Ron K. Eyre
  • Patent number: 6451442
    Abstract: In one embodiment, composite constructions of the invention are in the form of a plurality of coated fibers bundled together to produce a fibrous composite construction in the form of a rod. Each fiber has a core formed from a hard phase material, that is surrounded by a shell formed from a binder phase material. In another embodiment of the invention, monolithic sheets of the hard phase material and the binder phase material are stacked and arranged to produce a swirled composite in the form of a rod. In still another embodiment of the invention, sheets formed from coated fibers are arranged to produce a swirled composite. Inserts for use in such drilling applications as roller cone rock bits and percussion hammer bits, and shear cutters for use in such drilling applications as drag bits, that are manufactured using conventional methods from these composite constructions exhibit increased fracture toughness due to the continuous binder phase around the hard phase of the composites.
    Type: Grant
    Filed: April 14, 2000
    Date of Patent: September 17, 2002
    Assignee: Smith International, Inc.
    Inventors: J. Albert Sue, Ghanshyam Rai, Zhigang Fang
  • Patent number: 6406030
    Abstract: O-ring seals for rock bit bearings comprise a body formed from an elastomeric material having one or more lubricant additive uniformly distributed throughout to reduce the coefficient of friction and stick slick amplitude at O-ring seal surfaces. The lubricant additives are selected from the group consisting of polytetrafluoroethylene, hexagonal boron nitride, flake graphite, ultra-high molecular weight polyurethane, and mixtures thereof. O-ring seals made from elastomeric compositions of this invention comprise in the range of from about 85 to 99 percent by volume elastomeric material, and in the range of from about 1 to 15 percent by volume of the lubricant additives based on the total volume of the composition.
    Type: Grant
    Filed: October 8, 1997
    Date of Patent: June 18, 2002
    Assignee: Smith International, Inc.
    Inventors: Zhigang Fang, Robert Denton, Steven W. Peterson
  • Patent number: 6392190
    Abstract: An automated hardfacing system useful for hardfacing roller cones is disclosed. The automated system includes a robot with an arm, a positioner, and a controller which co-ordinates the alignment of the robot and the positioner. The robot holds a hardfacing torch and is capable of movement in three axes of movement. These axes are the x, y, and z axes of the Cartesian co-ordinate system. The positioner holds a roller cone and is capable of movement in at least two axes of movement. The movement includes tilting and rotation about a Cartesian axis. The hardfacing coating produced by the automated system has improved quality and consistency as compared to the one obtained by a manual process.
    Type: Grant
    Filed: September 15, 1998
    Date of Patent: May 21, 2002
    Assignee: Smith International
    Inventors: J. Albert Sue, Zhigang Fang, Alysia Canson White
  • Patent number: 6361873
    Abstract: Composite constructions of this invention comprise an ordered microstructure made up of multiple structural units that can be the same or different, and that comprise at least a first structural phase and a second structural phase. The first structural phase comprises a hard material that is selected from the group consisting of cermet materials, PCD, PCBN and mixtures thereof. The second structural phase is in contact with the first phase and comprises a material that is different than that selected to form the first structural phase. Additionally, the second structural phase is in contact with at least a portion of the first structural phase. Composite constructions of this invention can also have a multi-layer structures comprising two or more layers, wherein at least one of the layers comprises a composite construction having an ordered microstructure made up of the multiple structural units described above.
    Type: Grant
    Filed: February 8, 2000
    Date of Patent: March 26, 2002
    Assignee: Smith International, Inc.
    Inventors: Zhou Yong, Sujian J. Huang, Michael A. Siracki, Chris Cawthorne, J. Albert Sue, Ghanshyam Rai, Zhigang Fang
  • Publication number: 20020029909
    Abstract: A rotary cone bit, having a functionally-engineered surface of this invention, comprises a bit body having at least one leg extending therefrom, and a cone that is rotatably disposed on the leg. The cone typically comprises a plurality of cutting elements that project outwardly therefrom. The cutting elements comprises a cermet material selected from the group consisting of refractory metal carbides, nitrides, borides, carbonitrides and mixtures thereof. A functionally-engineered material is disposed over a surface portion of at least one of the cutting elements to form a wear resistant surface thereon. The wear resistant surface has a hardness that is different than that of the underlying cutting element. The wear resistant surface is provided by forming a conformable material mixture by combining one or more powders selected from the group consisting of cermets, carbides, borides, nitrides, carbonitrides, refractory metals, Co, Fe, Ni, and combinations thereof, with an applying agent.
    Type: Application
    Filed: May 1, 2001
    Publication date: March 14, 2002
    Inventors: Anthony Griffo, Zhigang Fang, Robert Denton
  • Publication number: 20020020564
    Abstract: Composite constructions of this invention comprise a first structural phase formed from a hard material selected from the group consisting of cermet materials, polycrystalline diamond, polycrystalline cubic boron nitride, and mixtures thereof, and a second structural phase formed from a material that is relatively softer than that used to form the first structural phase. The material selected to form the second structural phase can be the same or different from that used to form the first structural phase. The second structural phase is positioned into contact with at least a portion of the first structural phase. The composite construction includes repeated structural units that each comprise an ordered microstructure of first and second structural phases.
    Type: Application
    Filed: June 15, 2001
    Publication date: February 21, 2002
    Inventors: Zhigang Fang, Anthony Griffo, Alysia C. White
  • Patent number: 6319460
    Abstract: A metal-matrix diamond or cubic boron nitride composite and method of making the same are disclosed. The metal-matrix/diamond composite includes grains of diamond uniformly distributed in a metal matrix. Alternatively, grains of cubic boron nitride may be used. Suitable metals for the metal matrix material may include nickel, cobalt, iron, and mixtures or alloys thereof. Other transition metals also may be used. The metal-matrix/diamond or metal-matrix/cubic boron nitride composite has high fracture toughness due to its fine microstructure. Such a metal-matrix/diamond or metal-matrix/cubic boron nitride composite is suitable for use in blanks or cutting elements for cutting tools, drill bits, dressing tools, and wear parts. It also may be used to make wire drawing dies.
    Type: Grant
    Filed: August 10, 2000
    Date of Patent: November 20, 2001
    Assignee: Smith International, Inc.
    Inventor: Zhigang Fang
  • Patent number: 6244364
    Abstract: An earth-boring device such as a drill bit is disclosed. The earth boring device includes a rotary main cutting structure, an insert on the main cutting structure. The insert is formed of a composition having tungsten carbide and cobalt. The cobalt makes up less than approximately 9% by weight of the composition. The composition has a Rockwell A hardness greater than approximately an Hmin as determined by the following formula: Hmin=91.1−0.63X, where X represents a cobalt content by weight of the composition.
    Type: Grant
    Filed: January 22, 1999
    Date of Patent: June 12, 2001
    Assignee: Smith International, Inc.
    Inventors: Peter Cariveau, Robert Slaughter, Zhigang Fang