Abstract: A drill bit for drilling a wellbore, the drill bit having a body and at least one bearing. A rotary cone is rotatably attached to the bit body at the bearing. A lubricant reservoir is located in an inner portion of the bit body and is in fluid communication with the bearing. A communication port leads from the inner portion of the bit body to the exterior of the bit body. A fiber reinforced elastomeric pressure compensator diaphragm separates lubricant in the lubricant reservoir from the communication port.

Abstract: A method for lubricating a diamond bearing system of a downhole well tool involves dispensing a polyol lubricant for the reduction of friction between the two diamond surfaces. The lubricant forms a reduced friction surface film on the diamond. The polyol lubricant may be mixed with water. The polyol lubricant may contain ethylene glycol, glycerol, or a combination with water.

Abstract: The present disclosure includes a lubricant for use in a roller cone rock bit, where the lubricant comprises a non-grease formulation. The lubricant can comprise synthetic lubricating fluids and combinations thereof as well as combinations of synthetic fluid or fluids with mineral oil or oils. The lubricant can contain one or more additional ingredients and have a minimum viscosity of 100 centistokes at 212° F. The additional ingredients include fluid soluble or dispersed extreme pressure and antiwear additives, and solid lubricants.

Abstract: Downhole tool bearings are provided with diamond enhanced materials. The diamond enhanced materials comprise diamond grains in a matrix of tungsten or silicon carbide. A brazed diamond grit or diamond particles coated with a reactive braze may be utilized for bearing applications. Bearing rings formed at least in part with diamond enhanced material are installed on at least one of the bearing pin journal, the nose and the cone cavity. The bearing rings may be continuous rings or partial rings and attached to the journal pin or cone cavity. These may include thrust bearings, rollers, roller race, balls and ball races made of diamond enhanced material. These bearing surfaces also are formed at least in part with diamond enhanced material and attached to portions of the journal or cone bearing surfaces.

Abstract: A journal bearing element for use in forming a roller cone bit coupled to a bearing shaft to prevent circumferential sliding. Also included are material compositions of the journal bearing element. A journal bearing element is fixed in place relative to a head section and comprised of dense high purity powdered metal alloys with uniform micro-structure. A preferred material is comprised of a metal made of a carbon content of about 2.3% by weight, chromium of about 14% by weight, vanadium of about 9% by weight, and molybdenum at about 1% by weight.

Abstract: An earth boring bit has a bit body with at least one bearing pin. A cone is rotatably mounted on the bearing pin. A seal assembly is located between the cone and the bearing pin, the seal assembly having at least one flexible seal member. A flexible pressure compensating diaphragm is mounted in the body. The diaphragm has one side adapted to be exposed to borehole fluids and another side in contact with lubricant contained in bearing spaces between the cone and the bearing pin. The flexible seal member and the diaphragm are formed of a fluorinated elastomer. The elastomer is either a perfluoroelastomer (FFKM) or a fluoroelastomer (FKM).

Abstract: A thrust washer located between the thrust surfaces of the head and the cone of a drill bit allows for radial rotation between the cone, thrust washer, and head during drilling operations. The thrust washer also accommodates axial rotation between the cone and the head. The mating thrust surfaces between the thrust washer and the head are contoured to allow the thrust washer to rotate axially with the cone, and provide increased bearing contact between the thrust washer and the cone.

Abstract: A metal face seal for an earth boring drill bit where the drill bit has a bit body, at least one bit leg, a bearing pin on each bit leg, and a cone rotatably mounted on each bearing pin. The metal face seal is located in the cavity formed between the interior surface of the cone and the bearing pin. The metal face seal consists of a rigid seal ring having a forward surface that engages a rotating seal surface of the cone. An energizer ring biases the rigid seal ring toward the rotating seal surface. A secondary seal engages the bearing pin surface, the energizer ring, and the rigid seal ring. The secondary seal ring has a protuberance on its forward side for filling void spaces between the energizer ring, the rigid seal ring, and the secondary seal ring.

Abstract: An earth boring bit has a bit body with a depending bearing pin. An insert ring is mounted on the bearing pin. The insert ring has an inner diameter greater than an outer diameter of the bearing pin, defining a clearance between the insert ring and the bearing pin to allow the insert ring to float relative to an axis of the bearing pin. An inner seal is in sealing engagement with the bearing pin and the inner diameter of the insert ring. A cone is rotatably mounted on the bearing pin, the cone having a cavity containing an outer seal groove. An outer seal located in the outer seal groove is in dynamic sealing engagement with an outer diameter of the insert ring. An anti-rotation member engages a portion of the insert ring to prevent rotation of the insert ring.

Abstract: An earth boring bit has a bearing pin with a sleeve mounted on it. The sleeve is fixed against rotation but able to float relative to the bearing pin. A cone fits over and forms a bearing surface with the sleeve. The sleeve and bearing pin are configured to have a clearance between them that has a forward portion that progressively decreases in a rearward direction. The clearance progressively decreases in a forward direction from the rearward end of the sleeve. The cone and the sleeve are able to tilt in unison with each other relative to the bearing pin when the bit is loaded.

Abstract: An earth boring bit has a bearing pin with a sleeve mounted on it. The sleeve is fixed against rotation but able to float relative to the bearing pin. A cone fits over and forms a bearing surface with the sleeve. The sleeve and bearing pin are configured to have a clearance between them that has a forward portion that progressively decreases in a rearward direction. The clearance progressively decreases in a forward direction from the rearward end of the sleeve. The cone and the sleeve are able to tilt in unison with each other relative to the bearing pin when the bit is loaded.

Abstract: 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.

Abstract: An elastomeric seal ring is located between each bearing pin and each cone of an earth-boring bit. An excluder ring or band is imbedded within the inner diameter of the seal ring. A portion of the inner diameter of the seal ring as well as the excluder ring are in dynamic sealing contact with the bearing pin. The excluder ring may be harder and more wear resistant than the seal ring. The excluder ring may have lubricating properties. An outer excluder ring may be located on the outer diameter of the seal ring for engaging the cone to resist rotation.

Abstract: An earth boring bit has a bit body with a depending bearing pin. An insert ring is mounted on the bearing pin. The insert ring has an inner diameter greater than an outer diameter of the bearing pin, defining a clearance between the insert ring and the bearing pin to allow the insert ring to float relative to an axis of the bearing pin. An inner seal is in sealing engagement with the bearing pin and the inner diameter of the insert ring. A cone is rotatably mounted on the bearing pin, the cone having a cavity containing an outer seal groove. An outer seal located in the outer seal groove is in dynamic sealing engagement with an outer diameter of the insert ring. An anti-rotation member engages a portion of the insert ring to prevent rotation of the insert ring.

Abstract: 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.

Abstract: A method of forming a seal for a subterranean drilling tool employs irradiation. The seal is formed of a single homogeneous elastomeric material. The seal has an exterior surface with at least one portion that is in sliding engagement with part of a seal gland of the drilling tool. A property gradient is formed in the elastomeric material on at least this portion. The property gradient is formed by exposing the seal to an environment to define a property that changes from a first level to a second level without essentially changing the composition of the elastomeric material. The step of exposing is done by irradiating the seal with an electron beam.

Abstract: 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.

Abstract: An earth-boring bit has a bit body and at least one bearing shaft depending inwardly and downwardly from the bit body. The bearing shaft has a base where it joins the bit body. At least one cutter is mounted for rotation on the bearing shaft and has radial and axial surfaces that cooperate with the base of the bearing shaft to define a bearing seal gland. A bearing is defined between the cutter and bearing shaft. A seal element is disposed in the seal gland. A secondary seal is disposed in the seal gland opposite the cutter axial surface and cooperates with the seal element to at least partially seal the gland against entry of debris from the exterior of the bit.

Abstract: A heavy-duty lubricating grease is shown which includes a synthetic fluid base and a thickener system. The heavy-duty grease can be used in both rolling element and journal type rock bit bearings to drill in heavy-duty, high temperature applications, such as in the bearing structures of rock bits used to drill hot subterranean formations.

Abstract: An earth-boring bit has a bit body and at least one bearing shaft depending inwardly and downwardly from the bit body. The bearing shaft has a base where it joins the bit body. At least one cutter is mounted for rotation on the bearing shaft and has radial and axial surfaces that cooperate with the base of the bearing shaft to define a bearing seal gland. A bearing is defined between the cutter and bearing shaft. A seal element is disposed in the seal gland. A secondary seal is disposed in the seal gland opposite the cutter axial surface and cooperates with the seal element to at least partially seal the gland against entry of debris from the exterior of the bit.