Abstract: Disclosed herein are various embodiments of methods and systems for drilling an oil or gas well safely and efficiently using underbalanced or near-balanced drilling techniques, wherein the primary means of pressure control is a Annular Pressure Control Diverter positioned below the BOP stack, with a return flow pattern where no drilling fluid returns up the (traditional) annulus between the drill pipe and the production casing and instead drilling fluid returns up the annulus between the production casing and intermediate casing. Drilling fluid returns flow through a wellhead, instead of a flow spool conventionally located below an upper RCD, and hence to the drilling choke. This drilling approach eliminates the need for hydraulic fracturing and preserves the natural fracture system of the producing formation while providing additional safety measures. It also prevents the accidental or deliberate discharge or flaring of methane during drilling and production.
Abstract: An improved rigid face seal that minimizes pressure fluctuations in the lubricant in the vicinity of the seal assembly. The assembly has a first ring with a radial seal face that opposes and engages an opposed radial seal face of a second rigid ring. A first resilient energizer ring is compressed between opposed, generally conical surfaces, one on the first rigid seal ring and the other in a shaft seal groove. The mid-section of the first energizer ring is positioned relative to the journal bearing surface such that its inner periphery is inside the journal bearing surface and thereby defines an essentially constant, lubricant-filled volume between the seal assembly and the shaft seal groove--even as the cutter and seal assembly move relative to the shaft during drilling. A second energizer ring is provided to maintain sealing engagement between the radial seal faces of the first rigid ring and the second rigid ring.
Abstract: A method is shown for manufacturing a diamond filled compact of the type used as a cutting insert which is received in a cutting insert pocket in a drill bit. A hard metal jacket is provided having an open end and an open interior. The open interior is substantially filled with diamond. The diamond filled jacket is subjected to a temperature and a pressure sufficient to sinter the diamond and integrally form a diamond core within the hard metal jacket. The outer dimensions of the hard metal jacket are then reduced to a size selected to conform to a cutting insert pocket provided on the face of a drill bit.
Abstract: In an improved single piece earth boring bit of the type having a body including a solid bit face on one end and a shank on the opposite end for connection in a drill string, an improved cutting structure having diamond filled compacts used as a wear resistant inserts. The improved compacts have hard metal jackets and integrally formed diamond cores. The improved compacts are advantageously used as wear resistant inserts in the gage and heel rows of the bit.
Abstract: An earth boring bit having a body, pressure compensating lubricating system and cantilevered bearing shaft with an annular seal surface and a radial seal surface. A cutter is rotatably secured to the bearing shaft, with an annular seal recess having radial and cylindrical seal surfaces to oppose the seal surfaces on the body and bearing shaft to define a seal gland. A resilient and annular packing ring is compressed between the cylindrical seal surfaces, but has a length less than the minimum length of the gland. A shroud extends inwardly near the outer backface a selected distance behind the packing ring to bias it inwardly. The shroud extends inwardly toward the bearing not more than about 30% of the cross-sectional thickness of the O-ring in the relaxed condition. The O-ring is compressed in a range of about 10 to 15 percent.
Abstract: A method is shown for forming a diamond impregnated carbide containing dispersed diamond crystals, the crystals being formed via in-situ conversion of graphite to diamond. Graphite particles are blended with tungsten carbide power and a binder containing elemental powders known to be diamond catalyst. After blending, the powder is pressed into a green body of a desired shaped and sintered. After sintering, the body is loaded into a high temperature and pressure apparatus and exposed to conditions sufficient to convert the graphite to diamond.
Abstract: In an improved earth boring bit of the type having one or more rotable cones secured to bearing shafts, an improved cutting structure having diamond filled compacts used as a wear resistant inserts. The improved compacts have hard metal jackets and integrally formed diamond cores. The improved compacts are advantageously used as gage and heel row compacts when inserted in mating recesses provided on the exteriors of the rotatable cones.
Abstract: An improved hardfacing composition and method are shown for use in manufacturing an earth boring bit. The hardfacing composition is formed by combining titanium carbide with a hard-metal alloy of the iron or cobalt family. The hardfacing composition is then applied to the friction bearing surface of the rock bit.
Abstract: A heavy duty lubricating grease as shown which includes a multi-purpose heavy duty hydrocarbonaceous lubricant thickened by an alkaline soap to form a lubricating grease, molybdenum disulfide and powdered calcium fluoride. The heavy duty grease can be used in a journal bearing of a drill bit in heavy duty, high temperature applications, such as journal bearings on its used to drill hot subterranean formations.
Abstract: A three cone earth boring bit having circumferential rows of earth disintegrating teeth of wear resistant inserts of selected projection from the cone surfaces, one cone having an inner row separated from a heel row by a narrow circumferential groove and second cone having a hell-catching row that intermeshes with the narrow groove by an amount to minimize balling. A nozzle directs a jet stream with a high velocity core past the cone and inserts of adjacent cutters to the bore hole bottom to break up the filter cake while the lower velocity skirt strikes the material packed between the inserts of adjacent cores. A row of small diameter, recessed reaming inserts replaces the conventional heel row on the cone having a hell-catching row, thus providing space for the lateral displacement of the material generated between adjacent inserts in the critical heel-catching row.
March 21, 1990
Date of Patent:
January 15, 1991
Hughes Tool Company
Matthew R. Isbell, Rudolf C. O. Pessier
Abstract: A two-cone earth boring bit having non-opposite cones that minimize the tendency for off-center rotation or rough running. The bit is composed of two cones, each having a cantilevered bearing shaft with an axis extending inwardly and downwardly. A rotatable, generally conical cutter is mounted on each bearing shaft, each cutter having a conical gage surface to engage and define a borehole with a wall of select gage diameter. The axis of one cutter is skewed relative to the other to cause the conical gage surface of the two cones to engage the wall of the hole at points that are other than 180 degrees apart as compared to nonskewed cutters. These points are separated by a distance less than the selected gage diameter. A line between these points is separated from a line extending from one point through the rotatable axis on the bit by a selected angle. The body of the bit and/or stabilizers are separated from the wall of the hole by a distance less than the selected gage diameter.
Abstract: A one-piece drill bit is shown for use in drilling a borehole in an earthen formation. The bit includes a body having a face on one end and a shank on the opposite end. The face has a noise and a gage region. The gage region is bisected between an upper and lower stabilizing regions of full gage diameter cutter elements. An intermediate undercut region minimizes contact with the borehole wall while maintaining an effective gage length for the bit.
Abstract: An improved mechanical face seal for rock bits using rigid rings and energizers placed in recesses or grooves in the cutter and bearing shaft. The minimum diameter of the shaft groove is substantially equal to the relaxed inside diameter of the shaft energizer and the maximum diameter of the cutter recess is substantially equal to the relaxed outside diameter of the cutter energizer. The radii at the inner end of the shaft groove and the outer end of the cone groove conform to the relaxed cross-section of their respective energizers. The mean diameter of the shaft energizer is substantially equal to the cone journal diameter and the product of the mean diameter and cross-sectional diameter is the same for both energizers.
Abstract: An improved electrical transmission system for transmitting electrical power and data signals within a well bore having a string of tubular members suspended within it, each tubular member having a receiving end adapted for receiving data signals and a transmitting end for transmitting data signals, said receiving end and transmitting end being electrically coupled by a flexible printed planar conductor of the type having at least one substantially planar conductive band disposed between at least two layers of electrically insulating material.
Abstract: A polycrystalline diamond cutting element is shown which includes a mounting body having a leading face and a trailing face and a thin layer of super hard material carried on the leading face of the mounting body which defines a cutting face. The cutting face has a circular outer periphery which is interrupted to form a recess in the cutting face which continues through the mounting body. The recess mates in complementary fashion with the outer periphery of a second cutting element when the cutting elements are arranged side-by-side with the cutting faces thereof in a common plane.
Abstract: An earth boring bit having an improved two piece bearing and seal assembly containing a cantilevered bearing lug that is threaded to receive a mating bearing sleeve, the lug having a transverse shoulder intersected by a mouth on the sleeve to define a bearing shaft upon which is supported a rotatable cutter. A lubrication system includes a hydrostatic pressure compensator and seal means, the transverse shoulder being positioned inwardly of the seal means toward an inner end region of the lug to avoid exposure of the transverse shoulder of the lug and the mouth of the bearing sleeve to ambient drilling fluid. The seal means is a rigid face seal assembly which includes a rigid, sealing ring and a resilient energizer ring.
Abstract: An earth boring bit having a body and a cantilevered bearing shaft extending inwardly and downwardly from the body. A rotatable cutter with an open end is assembled over the shaft, which has a journal surface formed around a longitudinal axis. The cutter has a bearing surface sized to permit assembly over the journal surface of the shaft. At the open end of the cutter bearing surface is a seal recess which includes an intersecting wall that defines an annular, generally curved corner to oppose the journal surface of the shaft. The cutter bearing surface has a curved outer region that converges from the annular corner of the seal recess into an inner region to reduce the stress the corner induces upon the journal bearing surface of the shaft, including the stress induced by cutter cocking during drilling.
Abstract: An earth boring (rock) bit having a flexible diaphragm located inside the bearing shaft in a cavity between a threaded lug and a mating bearing sleeve. The diaphragm has an enlarged periphery, shaped somewhat like an o-ring, that is confined and sealed between opposed annular surfaces on the lug and the sleeve. The circular periphery of the diaphragm and cavity provide good compensation volume, from which excessive lubricant pressure is relieved by an enlarged portion which is punctured and contoured to discharge lubricant under excessive pressure while excluding drilling fluid. Simplicity and reliability are achieved by the elimination of multiple and complex manufacture and assembly operations.
Abstract: The present invention is an improved wellbore tool for coupling to a drill string at a threaded junction and adapted for use in a wellbore during drilling. A sensor is disposed in the wellbore tool for sensing a condition and producing a data signal corresponding to the condition. A self-contained power supply is disposed in the wellbore tool and coupled to the sensor for providing power to the sensor as required. The Hall Effect coupling transmitter means is carried by the sensor and for transmitting data from the Hall Effect coupling transmitter means to a Hall Effect coupling receiver carried by the drill string and disposed across the threaded junction from the wellbore tool, wherein data is transmitted across the threaded junction without requiring an electrical connection at the threaded junction.
Abstract: A torque reactor for a top drive drilling rig converts reactive torque on the top drive housing into a rotational torque on a torque shaft. The torque shaft extends vertically in the derrick parallel with the drive stem. A torque case carries two bushings, one of the bushings receiving the drive stem of the top drive and the other slidingly receiving the torque shaft. The drive unit bushing is rigidly connected to the housing of the top drive. The torque shaft bushing will transmit rotational force to the torque shaft. Linkages interconnect the bushings. Rotational torque imposed on the drive unit bushing creates a rotational torque in the torque shaft bushing. That torque is transmitted to the torque shaft which is held stationary to absorb the torque.