Smith International, Inc.

J Albert Sue

Zhigang Zak Fang

Ghanshyam Rai

Alysia C White

Gary Ray Portwood

Sujian Huang

Michael Allen Siracki

Chris Edward Cawthorne

Zhou Yong

Nephi M Mourik

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. These binder phases increase the overall fracture toughness of the composite by blunting or deflecting the tip of a propagating crack.

Composite constructions with oriented microstructure

A method for applying hardfacing to teeth on a drill bit is disclosed. The method includes applying the hardfacing to at least one of the teeth so as to have a thickness selected to correspond to a position about exterior surface of the tooth. In one embodiment, the hardfacing thickness is increased near the crest of the tooth, and is decreased near the root of the tooth on at least one flank of the tooth. In one embodiment, the thickness is selected by controlling the powder flow rate in a plasma transferred arc welding system. In another embodiment an angle subtended by flanks of the tooth is selected to provide increased strength to the tooth, and the hardfacing is applied to the tooth to cause exterior surfaces of the hardfacing corresponding to the flanks to subtend an angle selected to provide increased penetration of the tooth through earth formations while drilling.

Method for applying hardfacing to a substrate and its application to construction of milled tooth drill bits

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 W MB , where M is selected from the group consisting of iron, nickel, cobalt and alloys thereof. Particularly, a boride layer containing WC and W CoB may be formed over a cemented tungsten carbide substrate by a suitable boronizing process. Additional compounds present in the boride layer include CoB, W CoB , 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.

Boronized wear-resistant materials and methods thereof

A drill bit for cutting a formation that tends to form ridges comprises: a bit body having a bit axis, a plurality of rolling cone cutters rotatably mounted on the bit body, with each rolling cone cutter having a generally conical surface, a plurality of primary cutter elements extending from one of the cone cutters in a first row, each primary cutter element having an outer side and an inner side, and a plurality of ridge-cutting cutter elements extending from the same cone cutter, the first plurality of ridge-cutting cutter elements being positioned adjacent to the outer side of the first row of primary cutter elements. Each ridge-cutting cutter can be, but is not necessarily, on the same cone cutter as the primary cutter element adjacent to which it cuts, and is preferably positioned on a land or flat adjacent to that primary cutter element. Each primary cutter element in one or more rows can be provided with a ridge-cutting cutter element and the ridge-cutting cutter element can be angled with respect to the axis of the primary cutter element

Drill bit with ridge-cutting cutter elements

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.

Automated hardfacing system

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.

Composite constructions having ordered microstructures

A drill bit for cutting a formation that tends to form ridges comprises: a bit body having a bit axis, a plurality of rolling cone cutters rotatably mounted on the bit body, with each rolling cone cutter having a generally conical surface, a plurality of primary cutter elements extending from one of the cone cutters in a first row, each primary cutter element having an outer side and an inner side, and a plurality of ridge-cutting cutter elements extending from the same cone cutter, the first plurality of ridge-cutting cutter elements being positioned adjacent to the outer side of the first row of primary cutter elements. Each ridge-cutting cutter can be, but is not necessarily, on the same cone cutter as the primary cutter element adjacent to which it cuts, and is preferably positioned on a land or flat adjacent to that primary cutter element. Each primary cutter element in one or more rows can be provided with a ridge-cutting cutter element and the ridge-cutting cutter element can be angled with respect to the axis of the primary cutter element.

A new hardfacing composition is disclosed. In addition, a pulsed plasma transferred arc method for depositing hardfacing material with a higher content of carbide and lower dilution by a substrate metal is disclosed. The disclosed method produces a hardfacing coating which has a strong metallurgical bond to the substrate metal. The method includesthe following steps: (1) establishing a transferred plasma arc between an electrode and an area of a work piece, (2) optionally preheating the work piece to at least 250.degree. F., (3) forming a plasma column of inert gas in the arc by passing an electrical current between the electrode and the work piece, (4) feeding a stream of hardfacing material in powder form into the plasma column, and (5) pulsing the current between a pre-selected high pulse current value and low pulse current value while feeding the powdered hardfacing material. In this method, the low pulse current is selected to be sufficiently high to melt at least one component of the hardfacing material. The pulse rate and the high pulse current are selected to minimize the formation of a weld pool on the metal substrate during the hardfacing process. This method has applications in hardfacing any metallic work piece which requires wear resistance or erosion resistance. This method is especially effective in hardfacing roller cone surfaces and the milled teeth of a rock bit for erosion and wear protection.

Hardfacing compositions and hardfacing coatings formed by pulsed

Composite construction with oriented microstructure

Double cemented carbide composites comprise a plurality of first regions and a second ductile phase that separate the first regions from each other. Each first region comprises a composite of grains and a first ductile phase bonding the grains. The grains are selected from the group of carbides consisting of W, Ti, Mo, Nb, V, Hf, Ta, and Cr carbides. The first ductile phase is selected from the group consisting of Co, Ni, Fe, alloys thereof, and alloys with materials selected from the group consisting of C, B, Cr, Si, and Mn. A preferred first region comprises tungsten carbide grains that are cemented with a cobalt first binder phase and which are in the form of substantially spherical pellets. The second ductile phase is selected from the group consisting of Co, Ni, Fe, W, Mo, Ti, Ta, V, Nb, alloys thereof, and alloys with materials selected from the group consisting of C, B, Cr, and Mn. A preferred second ductile phase is cobalt. Additionally, additives such as those selected from the group consisting of carbides, nitrides, and borides can be added to the second ductile phase to provide improved properties of wear resistance. The composites are prepared by combining hard phase particles formed from the grains and first ductile phase, with the second ductile phase material under conditions of pressure and heat, and have improved properties of fracture toughness and equal or better wear resistance when compared to conventional cemented tungsten carbide materials.

Growing community of inventors

The Woodlands, TX, United States of America

J Albert Sue