摘要:
An earth-boring bit has a bit body that includes head sections, each having depending bit legs with a circumferentially extending outer surface, a leading side, and a trailing side. A bearing shaft depends inwardly from each of the bit legs for mounting a cutter. The bit includes a beveled surface formed at a junction of the leading side and the outer surface of each bit leg. The beveled surface is angled relative to a radial plane emenating from the axis of the bit. The angle of the beveled surface is at least 20 degrees, and extends to an inner surface of the bit leg. The bit can also have a layer of hardfacing on the leading, trailing and shirttail surfaces of the bit leg. A diversion finger of hardfacing extends circumferentially to direct cuttings.
摘要:
An earth-boring bit has a bit body that includes head sections, each having depending bit legs with a circumferentially extending outer surface, a leading side, and a trailing side. A bearing shaft depends inwardly from each of the bit legs for mounting a cutter. The bit includes a beveled surface formed at a junction of the leading side and the outer surface of each bit leg. The beveled surface is angled relative to a radial plane emenating from the axis of the bit. The angle of the beveled surface is at least 20 degrees, and extends to an inner surface of the bit leg. The bit can also have a layer of hardfacing on the leading, trailing and shirttail surfaces of the bit leg. A diversion finger of hardfacing extends circumferentially to direct cuttings.
摘要:
A gage scraper cleans mud from the gage surface of a rotary cone of a drill bit. The bit has a body having at least one leg depending therefrom, a bearing pin secured to each leg, and a rotary cutting cone mounted to the bearing pin. The cone has a conical gage surface. The gage scraper mounts on the inside of each leg and protrudes from the leg toward the cone into close proximity with the gage surface.
摘要:
Earth-boring tools include wear-resistant materials disposed in at least one recess formed in an exterior surface of a body thereof. Exposed surfaces of the wear-resistant material are substantially level with exterior surfaces of the body adjacent the wear-resistant material. In some embodiments, recesses may be formed in formation-engaging surfaces of blades of earth-boring rotary tools, adjacent one or more inserts secured to bodies of earth-boring tools, or adjacent one or more cutting elements secured to bodies of earth-boring tools. Methods of forming earth-boring tools include filling one or more recesses formed in an exterior surface of a body with wear-resistant material and causing exposed surfaces of the wear-resistant material to be substantially level with the exterior surface of the body.
摘要:
An air-cooled turbine blade is provided having an airfoil shape defined by a convex suction side wall, a concave pressure side wall, a leading edge, a trailing edge, a root and a tip, each wall including an interior surface that defines an interior with the edges, root and tip. The blade includes a plurality of independent cooling circuit flow paths within the blade interior and a roughened surface. The roughened surface is formed on an interior surface of at least one of the convex suction side wall and the concave pressure side wall, the roughened surface comprising a plurality of cylindrical depressions. Each depression includes a cylindrical wall coupled to a bottom wall by a chamfered edge formed therebetween, and the roughened surface defines at least a portion of one of the flow paths of the plurality of independent cooling circuit flow paths. Methods for forming the blade are also provided.
摘要:
An encapsulant is described for an optoelectronic device or optical component, which provides a coefficient of thermal expansion of less than 50 ppm/° C., with a variation of less than ±30%, and further provides an optical transmittance of at least 20% at a wavelength in the range of 400 to 900 nm, at an encapsulant thickness of about 1 mm. The encapsulant includes a filler consisting essentially of glass particles having diameters smaller than 500 μm, being essentially free of titania and lead oxide, and having a refractive index in the range of 1.48 to 1.60, with a variance of less than about 0.001. A method for making the encapsulant also is described, the method including steps of (1) processing the glass to form particles having diameters between 1 and 500 μm, (2) preparing an epoxy resin composition having at a cured stage a refractive index close to that of the glass filler particles, (3) mixing the epoxy resin composition with the filler particles to form a filled epoxy resin composition, (4) encapsulating an optoelectronic device with the filled epoxy resin composition, and (5) curing the filled epoxy resin composition.
摘要:
A cooled shroud assembly includes an angled slot and a plurality of dilution jet openings. The shroud forward cavity is modified such that at least one recirculation zone is produced. The angled slot forces an axial change in momentum of the hot gas flow and increases radial and axial pressure variation attenuation. The cooled shroud assembly isolates the shroud structure and seals from the hot flow path and a cooling flow from the dilution jet openings dilutes the hot gas flow. A series of recirculation zones shields the shroud carrier and high pressure seals from the hot gas flow.
摘要:
A new and distinct peppermint plant ‘Clackamas’ characterized by its resistance to Mint rust (Puccinia menthe Pers), Mint wilt (Ferticillium dahliae and Verticillium albo-atrum), and Spider mites as well as a more upright growth habit and a lighter green color the Black Mitcham peppermint plant.
摘要:
Compounds represented by formula I: or pharmaceutically acceptable salts and solvates thereof, wherein A, B, B′, X, Y, R1, R1′, R2, R2′, R3, R3′, R5, R5′, R6, m, n, or p are as defined herein, are useful for treating flaviviridae viral infections.
摘要:
A diffuser particle separator may be integrated into a gas turbine engine to remove corrosive dust and salt particles from the engine's core air flow. The air flow may pass over a series of particle accumulator entrance orifices, trapping particles in a particle accumulator while allowing the air flow to continue unimpeded. Since dust deposits may become molten at high temperatures, removal of dust from the core and secondary airflow may be critical for long-life superalloy and ceramic components, particularly those with small diameter air-cooling holes and thermal barrier coatings.