摘要:
A hybrid-type earth boring drill bit is described having fixed cutting blades and rolling cones with cutting elements, wherein the rolling cones are associated with a spindle assembly that may be optionally divorced from the head pin assembly, and which includes bearing members that further include a plurality of polycrystalline diamond elements.
摘要:
A modular cutting-teeth bit having controllable specific pressure for drilling includes: a module (1), a modular unit (2), a bit body (3), conventional cutting teeth (4) and a nozzle (5). According to mechanical performance of the rocks in the strata drilled and requirements of drilling well, a combination of shapes, sizes and numbers of the module and the modular unit is optimized; effective abrasion edge length of the cutting unit on a certain portion of the bit is controlled; and a constant specific pressure of the cutting unit of the bit during the drilling process is maintained.
摘要:
A rotary cone drill bit includes: a body, a leg depending from the body, a bearing shaft extending from the leg and a cone mounted to the bearing shaft. The leg includes a leading transitional surface. A bottom surface of a hard material plate is attached to a substantially conforming surface of the leg in a position where the hard material plate is disposed on a floor surface formed in or by the leading transitional surface of the leg.
摘要:
Polycrystalline compact tables for cutting elements include regions of grains of super hard material. One region of grains (“first grains”) and another region of grains (“second grains”) have different properties, such as different average grain sizes, different super hard material volume densities, or both. The region of first grains and the region of second grains adjoin one another at grain interfaces that may include a curved portion in a vertical cross-section of the table. In some embodiments, discrete regions of the first grains may be vertically disposed between discrete regions of the second grains. As such, the tables have ordered grain regions of different properties that may inhibit delamination and crack propagation through the table when used in conjunction with a cutting element. Methods of forming the tables include forming the regions and subjecting the grains to a high-pressure, high-temperature process to sinter the grains.
摘要:
A hardfacing composition comprising an iron-based binder alloy; and a carbide phase comprising a sintered carbide and a cast tungsten carbide, wherein the cast carbide is present in a quantity of at least 22% by weight, based on the total weight of the carbide phase, and the cast carbide comprises particles having sizes in the range of from 30 to 60 mesh. Also provided is a hardfacing composition comprising an iron-based binder alloy; and a carbide phase comprising a super dense sintered carbide and one or more additional carbide materials, wherein the super dense sintered carbide is present in a quantity of at least 10 percent by weight (% w), based on the total weight of the carbide phase, and comprises particles having sizes in the range of from 16 to 40 mesh. Included are methods of manufacturing such hardfacing compositions and downhole tools having such improved hardfacing compositions applied thereon.
摘要:
A cutting structure may include an outer support element; and an inner rotatable cutting element comprising a cutting surface at its upper end; wherein the inner rotatable cutting element comprises at least one line contact along a circumferential side surface thereof and/or at least one point contact at a bottom face thereof.
摘要:
The present invention is related to drilling equipment technologies in petroleum and natural gas, mining engineering, infrastructure construction, geological and hydrological projects. More particularly, it discloses a composite drill bit with scraping-wheel cutting unit being disposed on fixed-blade. The drill bit comprises a bit body, fixed-blades and scraping-wheels. The fixed-blade with cutters fixed thereon is configured on the bit body. The angular deflection of the scraping-wheel is in the range of 20°≦|α|≦90°. At least one scraping-wheel cutting unit, which comprises the scraping-wheel shaft and the scraping-wheel with cutters disposed thereon, is disposed on the fixed-blade forming a rotary connection. This invention saves the space of cutting structure so as to fulfill the potential of alternating cutting and cross-cutting for cutters of the bit, and consequently, increases the overall bit performance.
摘要:
A scraping-wheel drill bit with a bit body configured at its upper extend for connection into a drillstring, comprising: a bit body (1) with at least one bit leg (3), and at least one scraping-wheel (2) set with a cutter-row (4). The scraping-wheel (2) is mounted for rotation on the corresponding bit leg (3) with a large angular deflection α which lies in the range of 20°≦|α|≦90°. The cutters on the scraping-wheel break rocks by means of successive scraping, forming a spiral-like tracks on the bottomhole, thus achieving high rock-breaking efficiency, even wear, high cooling performance, and a longer service life for the cutters, bearings and the drill bit.
摘要:
Disclosed is a rolling cone drill bit with inner row cutting teeth having portions shielded with an erosion-resistant material that differs in material properties from the tooth's core portion that is more impact resistant. The tooth includes shielding on at least a portion of the upstream end and along portions of the flanking surfaces. It includes shield-free portions on the flanks between the root and the tooth crest. Most of the tooth's perimeter is made of the core material and is free of shielding. Gage row teeth may be angled and form a channel to direct drilling fluid from the gage region of the borehole to locations where the inner row teeth are generating most cuttings. Nozzles are provided with non-uniform orientations.
摘要:
A drill bit includes a bit body comprising at its upper end a connection adapted to connect to a drill string and at its lower end a plurality of journals extending downwardly and radially outward from a longitudinal axis of the bit. A plurality of roller cones are rotatably mounted on the plurality of journals and at least three rows of cutting elements are disposed on each of the plurality of roller cones. The outermost row of the at least three rows of cutting elements has an extension height to diameter ratio greater than a mid row, and the mid row has an extension height to diameter ratio greater than an innermost row.