A non-weldable workpiece may be affixed to a weldable workpiece by friction stirring the weldable workpiece to plasticize and extrude at least a portion thereof into a recess in the non-weldable workpiece. The weldable workpiece may then be welded to a body of a downhole tool to enable the welding of a non-weldable workpiece onto a body to increase the wear-resistance of the body.

A polycrystalline diamond (PCD) composite compact element 100 comprising a substrate 130, a PCD structure 120 bonded to the substrate 130, and a bond material in the form of a bond layer 140 bonding the PCD structure 120 to the substrate 130; the PCD structure 120 being thermally stable and having a mean Young's modulus of at least about 800 GPa, the PCD structure 120 having an interstitial mean free path of at least about 0.05 microns and at most about 1.5 microns; the standard deviation of the mean free path being at least about 0.05 microns and at most about 1.5 microns. Embodiments of the PCD composite compact element may be for a tool for cutting, milling, grinding, drilling, earth boring, rock drilling or other abrasive applications, such as the cutting and machining of metal.

A heavy weight drill pipe for use in a downhole tool. The heavy weight drill pipe may include a tool joint made of a first steel alloy selected from the group consisting of AISI 4135, AISI 4137, AISI 4140, AISI 4142, AISI 4145, and AISI 4147. The tool joint may have as radial thickness between about 3.0 cm and about 5.7 cm. The heavy weight drill pipe may also include a pipe made of a second steel alloy selected from the group consisting of AISI 4135, AISI 4137, AISI 4140, AISI 4142, AISI 4145, and AISI 4147. The pipe may have a radial thickness between about 1.6 cm and about 3.3 cm. A weld region may be formed between the tool joint and the pipe. The weld region may be formed by friction welding the tool joint to the pipe.

A method for the material-removing machining of a workpiece by laser beam pulses. The laser beam pulses are directed to impact points on the surface of a volume to be removed of the workpiece in order to cut away material from the volume to be removed. Cutting away the volume to be removed results in a new contour surface to be produced on the workpiece. An impact angle of the laser beam pulses relative to the contour surface to be produced is set in accordance with a predefined condition during the removal of at least part of the volume to be removed that directly adjoins the contour surface to be produced. According to this condition, the impact angle is the same as a threshold angle (as), or somewhat smaller. The threshold angle corresponds to the impact angle at which an effective laser energy density at the impact point of the laser beam pulses on the contour surface to be produced is equal to a threshold fluence. Material is only removed at an impact point if the effective laser energy density is greater than the threshold fluence. As a result, only those volume elements of the volume to be removed that are adjacent to the desired contour surface to be produced are cut away. By controlling, in an open- or closed-loop manner, the impact angle it is therefore possible to generate with very high precision the desired contour surface on the workpiece.

A downhole component including a first portion; a second portion; a controlled failure structure between the first portion and second portion. A method for improving efficiency in downhole components.

Methods for welding a particle-matrix composite body to another body and repairing particle-matrix composite bodies are disclosed. Additionally, earth-boring tools having a joint that includes an overlapping root portion and a weld groove having a face portion with a first bevel portion and a second bevel portion are disclosed. In some embodiments, a particle-matrix bit body of an earth-boring tool may be repaired by removing a damaged portion, heating the particle-matrix composite bit body, and forming a built-up metallic structure thereon. In other embodiments, a particle-matrix composite body may be welded to a metallic body by forming a joint, heating the particle-matrix composite body, melting a metallic filler material forming a weld bead and cooling the welded particle-matrix composite body, metallic filler material and metallic body at a controlled rate.

A method of manufacturing a roller cone includes machining a cone blank and thereby defining one or more land surfaces and one or more insert grooves on the cone blank, surface hardening the cone blank, and milling a plurality of recesses into at least one of the one or more land surfaces. The method further includes subjecting the cone blank to a quenching process, forming an insert hole at each recess, and inserting an insert into each insert hole.

A method for producing a drill shaft for a wet drill bit includes forming N, where N≥1, strip materials into a tubular body where the tubular body is integrally joined at strip edges of the strip materials by N connection welds. At least one strip material of the strip materials is provided with at least one recess before the integral joining of the strip edges.

Methods, systems, and apparatus for carrying out rapid on-site optical chemical analysis in oil feeds are described. In one aspect, a system for manufacture of a tool includes a deposition reactor configured for molecular layer deposition or atomic layer deposition of metal powder to manufacture coated particles, a fabrication unit configured for 3D printing of the tool, and a controller that controls the deposition reactor and the fabrication unit, wherein the fabrication unit and the deposition reactor are integrated for automated fabrication of the tool using the coated particles from the deposition reactor as building material for the 3D printing.

A downhole cutting tool includes a tool body with a cutting element or cutting element pocket thereon. At least a portion of the tool body or an attachment thereto is a metal matrix composite formed from metal carbide particles dispersed in a continuous metal matrix. The metal carbide particles make up less than 45 wt % of the metal matrix composite and/or less than 30 vol % of the metal matrix composite. The continuous metal matrix may also be formed from a metal or metal alloy other than Ni—Si—B and/or have a transverse rupture strength greater than 150 ksi and a fracture toughness over 22 ksi*in.sup.0.5.