Harold Sreshta - Houston TX Eric F. Drake - Galveston TX
Assignee:
Schlumberger Technology Corporation - Sugar Land TX
International Classification:
B22F 302
US Classification:
419 68
Abstract:
The present invention is a new method for forming a high density hard facing rod. The rod is particularly suitable for hardfacing downhole tools including both fixed cutter and rolling cutter drill bits, bias pads for downhole rotary steerable systems, and stabilizers, and for other types of tools requiring strong and wear resistant hardfacings. The method includes the steps of: preparing a powder mix comprising carbide and metal powders, a fugitive binder, and other additives to render a moldable rheology; forming the powder mix into a powder core encased with a metal sheath to form a core-sheath assembly; and isostatically compacting the core-sheath assembly to densify the core to at least 65% of theoretical density and mechanically attach the sheath. The core fugitive binder along with residual volatile constituents may be thermally removed with or without vacuum, reducing, or inert environment prior to weld application of the composite rod.
Harold A. Sreshta - Houston TX Eric F. Drake - Galveston TX
Assignee:
Schlumberger Technology Corporation - Sugar Land TX
International Classification:
B22F 302
US Classification:
419 66, 419 14, 419 38
Abstract:
The present invention relates to a method of forming a powder rod core comprising injecting a powder mix material into a mold, moving the mold to a curing station, and injecting material into a second mold.
Eric F. Drake - Pearland TX Harold A. Sreshta - Houston TX Nigel Dennis Griffin - Whitminster, GB
Assignee:
Camco International (UK) Limited
International Classification:
C23C 1627
US Classification:
4272498, 42724913
Abstract:
A method of thermally treating a preform element, of the kind having a facing table of polycrystalline diamond bonded to a substrate of cemented tungsten carbide, comprises the steps of: (a) heating the element to a soaking temperature of 550-625Â C. , and preferably about 600Â C. , (b) maintaining the element at that temperature for at least one hour, and (c) cooling the element to ambient temperature. The resulting preform element has a substrate with a cobalt binder including a substrate interface zone with at least 30 percent by volume of the cobalt binder a hexagonal close packed crystal structure. This reduces the risk of cracking or delamination of the element in use.
Harold A. Sreshta - Conroe TX, US Hector Adrian Sanchez - Houston TX, US Eric F. Drake - Galveston TX, US Neerali Janubhai Desai - Houston TX, US
International Classification:
E21B 17/04 E21B 17/046
US Classification:
1753252, 1753254
Abstract:
A turbine matrix sleeve in accordance with the invention includes an inner cylindrical structure made up of a first material. The inner cylindrical structure may include multiple blades and multiple channels running between the blades along an outside diameter thereof. The inner cylindrical structure further includes threads, such as right-hand or left-hand threads, on an outer surface thereof. An outer layer, made up of a second material different from the first material, is integrally bonded to the threads. This outer layer may be optionally embedded with hardened inserts or buttons, such as PDC inserts, diamond inserts, TSP inserts, or the like. The threaded surface on the inner cylindrical structure significantly improves the bond between the outer layer and the inner cylindrical structure and creates a mechanical lock therebetween.
Composite Structure Having A Non-Planar Interface And Method Of Making Same
Harold Sreshta - Houston TX, US Eric Drake - Galveston TX, US
International Classification:
E21B 10/36
US Classification:
175426000, 175432000
Abstract:
A composite structure includes a first portion comprising a first metallic material, a monolayer of particles extending into and bonded with the first portion, and a second portion comprising a second material, the second portion bonded with the monolayer of particles and extending into interstices between the particles. A method for fabricating a composite structure includes bonding a monolayer of particles to a first portion comprising a first metallic material, such that the monolayer of particles extends into the first portion and bonding a second portion comprising a second material to the monolayer of particles, such that the second portion extends into interstices between the particles.
Hard Composite With Deformable Constituent And Method Of Applying To Earth-Engaging Tool
Harold Sreshta - Conroe TX, US Eric F. Drake - Galveston TX, US Douglas B. Caraway - Conroe TX, US
International Classification:
E21B 10/00 B32B 3/26 B22F 1/00 B21D 22/00
US Classification:
175425, 4283044, 75252, 72352
Abstract:
A hardmetal composite used as wear-resistant surfaces and inlays in earth-engaging equipment includes more than one hardphase. At least one hardphase has a high average particle size, for example, from 100 μm to 2000 μm. The hardphases vary in terms of particle size, hardness, and binder content, and at least one hardphase includes a particulate constituent capable of plastic deformation that comprises at least 1% residual porosity.
A rolling cutter drill bit is disclosed having cutters manufactured by powder metallurgy techniques, said cutters having gradient composite metallic structures in the cutting areas arranged to reduce or eliminate physical and metallic discontinuities and stress risers.
Cutting teeth for rolling cutter bits, including cutter inserts, cutter teeth formed in place, or formed separately and welded in place, etc. , are formed by powder metallurgy as a densified powder metallurgical composite of at least two varying phases, said composite having a substantially continuous mechanical property gradient therethrough. One of said phases is preferably a refractory compound and another phase is a binder metal or alloy. The gradient is from one mixture of said phases in one region having hardness or wear resistant properties to another mixture of said phases in another region having toughness properties.
Totaro Elementary School Lawrenceville VA 1997-2001, Sturgeon Elementary School Lawrenceville VA 1997-2006, Russell Junior High School Lawrenceville VA 2002-2006
Community:
Dedra Jolly, Eric Drake, Elizabeth Goodwyn, Carleton Coleman, John Stith, Lawrence Beasley