Abstract: The present invention relates to a method of determining the proppant friction generated in a fracture of a subterranean formation during a hydraulic fracturing treatment involving injection stages of pad and of proppant-laden fluids. This method is based on close monitoring of surface pressure to define a “net pressure rate” which defines an increase or decrease of net pressure while the job is being pumped, and then relates it with the pressure changes observed with the onset of proppant stages of varying concentrations.

Abstract: A universal joint assembly includes a cross and an end fitting having respective rotational centers that are precisely co-axially aligned with one another to minimize rotational imbalance. The cross has a pair of outwardly extending trunnions, upon which respective bearing cups are rotatably supported. A span control sleeve is press fit about each of the bearing cups. Each of the span control sleeves includes an outwardly extending flange portion that is precisely located relative to the rotational center of the cross. The end fitting is formed having a pair of inwardly facing surfaces that are precisely located relative to the rotational center of the end fitting. When the cross is assembled with the end fitting, the outwardly extending flange portions of the span control sleeves abut the inwardly facing surfaces of the end fitting. As a result, the rotational center of the cross is precisely aligned with the rotational center of the end fitting.

Abstract: A twist ring for placement in an annular groove having a generally C-shaped region with two ends. The twist ring has a first leg extending from one end and a second leg extending from the second end. The twist ring additionally has at least one finger projecting inwardly from the C-shaped region.

Abstract: A shaft assembly with recirculating ball roller joint unit for use with an automotive steering column or the like has an inner shaft extending lengthwise within an outer shaft. A recirculating ball joint is provided between the shafts. The ball joint includes a shell assembly having two shells which together surround the inner shaft. Each shell has an outer cage, an inner cage and a retainer defining ball races, with balls recirculating in the races in rolling engagement with the inner shaft.

Abstract: Wheel bearing unit for motor vehicles, comprising a roller bearing and a constant-velocity joint arranged inside the roller bearing. The outer part of the constant-velocity joint is situated opposite the inner ring flange of the bearing with clearance, and the outer part has an axially aligned extension section, in the area of which torque is transmitted. Only the extension section has radially directed projections, which project into recesses of the inner ring or the inner ring flange.

Abstract: The invention is an apparatus for cleaning auger flightings having a mounting attachable to an auger support frame, and an auger cleaning device having a single shaft positioned in the mount; a disk slidable on and rotatable about the shaft; the disk having a series of lobes extending radially from the disk and adapted to be interposed in the flightings of an auger; a stop fixable on the shaft; and a spring to bias the disk against the stop.

Abstract: Boot systems and boot attachment methods are provided to protect a double-tube vehicle driveshaft from premature wear or corrosion. One boot system comprises a boot portion having annular folds, opposite ends, and collar portions. The collar portions adjoin the boot portion at its opposite ends. At least one of the collar portions has a splined portion. The boot system may be utilized in a driveshaft comprising first and second members having splined portions. The second member of such a driveshaft is telescopically resident within the first member, and the splined portion of the first member cooperates with the splined portion of the second member. The boot attachment method involves sliding the boot over at least a part of the first and second members of the driveshaft, and securing the first and second collar portions to the respective first and second members.

Abstract: A cross member unit for universal joints has a cross member (6) with four trunnions (17). Each two trunnions define a common longitudinal axis (7). Each trunnion (17) has an end face (18), a first sealing face (21) and a pre-sealing face (24). The pre-sealing face (24) is remote from the end face 18 and has a diameter increasing relative to the first sealing face (18). A bearing bush (9) is on each trunnion (17). Each bearing bush (9) has an open end 29 and has rolling contact members 27 rotatably supporting the trunnion (17) around the longitudinal axis (7) of the trunnion (17). An annular seal (30) is provided in each bearing bush 9. The annular seal (30) is held in the bearing bush 9 by a press fit. The annular seal (30) includes an annular carrier (31) which projects from the open end (29) of the bearing bush (9). The annular seal includes at least one first sealing lip (35) which is in contact with the first sealing face (18) of the trunnion (17).

Abstract: It is intended that the induced thrust and slide resistance of a constant velocity joint should be further reduced. To this end, there is provided a constant velocity joint comprising an outer joint member having three track grooves each having circumferentially opposed roller guide surfaces, a tripod member having three radially projecting leg shafts, a roller inserted in each track groove, and a ring fitted on each leg shaft to rotatably support the roller, the roller being movable along the roller guide surfaces axially of the outer joint member. The roller includes a set of annular roller segments, with a plurality of balls interposed between outer raceway surfaces formed on the inner periphery of the annular roller segments and a single inner raceway surface formed on the outer periphery of the ring.

Abstract: An instrument support member with an integrated air conducting unit to be mounted between the A-columns of a motor vehicle is composed of at least two metal shells which are connected to each other by plasma jet welding with an effective focus remote from the nozzle, and a plastic tube surrounded by the shells. The plastic tube is mounted at a radial distance from the shells.

Abstract: The coaxial first and second flywheels of a torsional vibration damper, e.g., in the power train of a motor vehicle, are rotatable relative to each other against the opposition of one or more arcuate coil springs which is or are confined in an annular chamber defined by at least one of the flywheels. One end of the coil spring or each coil spring bears, directly, or indirectly, against a single retainer or against one of several discrete retainers on one of the flywheels, and the other end of the coil spring or each coil spring bears, directly or indirectly, against a single retainer or against one of several discrete retainers of the other flywheel. At least one slide is interposed between the radially outermost portions of discrete convolutions provided between an internal surface of the at least one flywheel and one or more discrete coil springs, one for each slide.

Abstract: A constant velocity universal ball joint comprising an outer joint part having a first axis and comprising an inner aperture in which there are provided substantially longitudinally extending first ball tracks, an inner joint part having a second axis and forming a ball hub positioned in the inner aperture of the outer joint part and being provided with substantially longitudinally extending second ball tracks, torque transmitting balls guided in first and second ball tracks associated with one another in pairs, and an annular ball cage which is arranged between the outer joint part and inner joint part and comprises circumferential distributed ball windows in which the individual balls are held in a common plane and guided on to the angle-bisecting plane between the first axis and the second axis, wherein at least the ball tracks of one of the joint parts—outer joint part or inner joint part—comprise a track cross-section which remains uniform along the length of same, whose second derivative ris

Abstract: An axial plunging unit for transmitting torque within a driveline, includes a profiled sleeve (11) with circumferentially distributed longitudinally extending first ball grooves (12), a profiled journal (13) with circumferentially distributed longitudinally extending second ball grooves (14), and balls (15) which are arranged in pairs of first and second ball grooves (12, 14) in groups (k) of balls, wherein the number of first ball grooves (11) corresponds to m times the number k of the groups of balls and wherein the longitudinal axes of the first, second, etc. to the mth of the first ball grooves 12, as counted circumferentially, are positioned on different pitch circle diameters.

Abstract: A torsionally flexible coupling having a rotational axis (1), including a first ring (2) and a second ring (3, 4), which enclose each other [one enclosing the other] at a radial distance, at least one ring-shaped first spring element (5) made of elastomeric material being positioned in the annular clearance (13) formed by the radial distance; and a belt pulley (7) being fastened, relatively having torsional flexibility, to at least one of the rings (2; 3, 4) with the aid of a second spring element (6) made of an elastomeric material, and being supported on at least one of the rings (2; 3, 4) at least in the radial direction with the aid of a sliding bearing (8, 9); the sliding bearing (8, 9) being formed by a rubber layer (9) having at least two embedded sliding rings (8).

Abstract: A flexible shaft coupling device having two hubs with jaws extending from each hub toward the other hub. A flexible elastomeric belt or cushions fill the gaps between adjacent pairs of jaws. A retaining ring is mounted around the belt or cushions to keep the belt or cushions securely in place. There are a plurality of locking pins adjacent to the edges of the retaining ring and preferably on the interior surface of the ring. These are received in grooves cut in the exterior surface of the belt. When the retaining ring is placed over the belt, the belt is retained between the locking pins. Raised portions or nubs are placed at the entrance and exits of the grooves so that when the ring is rotated with respect to the belt, the locking pins pass over the nubs to securely lock the retaining ring around the edges of the belt. Alternatively the edges of the belt or cushions are tapered to engage the pins in locking engagement.

Abstract: Drive shaft coupling having in-series bellows segments of different flexural resistance. The bellows segment nearest a tube section presents less flexural resistance than the immediate following bellows segment. Each individual bellows segment may be dimensioned in such a way that stress is distributed evenly over all bellows segments so that the component may be optimized; for example, with respect to installation and strength.

Abstract: Ring-shaped ridges (23, 24) that extends in the circumferential direction and is capable of falling toward a bellows portion (12) when a larger cylindrical portion (11) comes into press contact therewith are formed on the outer peripheral surface of the bushing (2). Since the ring-shaped ridges (23, 24) fall toward the bellows portion (12) when being tightened, when a pressure is exerted from grease, the pressure acts in the direction of restoring the ring-shaped ridge (23) to the original posture. Therefore, the ring-shaped ridge (23) serves as a dam and is brought into press contact with the larger cylindrical portion (11) at a high bearing pressure.

Abstract: The invention concerns a driving disc for transmitting the torque from one drive unit to a hydrodynamic converter (2). The driving disc (5) has one leg (51) extending in radial direction and fastened on the output shaft (1) of the drive unit and one leg (52) extending in axial direction and fastened on supporting devices (4) of a housing (3) of the hydrodynamic converter (2). By recesses (10) spaced apart from each other in peripheral direction of the driving disc (5), there are formed in the leg (52) extending in axial direction bracket arrangements which serve to fasten the leg (52) extending in axial direction on supporting device (4) situated in the housing (3). The bracket arrangements are each formed by tongue-shaped brackets (11, 12; 11′, 12′) which seen in peripheral direction extend successively from both sides of the recess (10). The end areas of the brackets (11, 12; 11′, 12′) are each fastened on one supporting device (4).

Abstract: My universal joint will use the outer and inner members to hold the balls in alignment. The male or female part would hold the ball in a half spherical recess and the other component would have a race groove to allow movement. It will also have means of attachment on each end with both ends being integral components of the final product. The male and female components could be made out of a pipe, tube, bar or cylinder of any length desired. The male component could consist of the unit holding 3 balls. This method would turn the friction wear of a rubbing surface into a rolling movement that would allow more speed of motion and less vibration. If necessary, in order to provide more bearing surface, increase torque, speed and reduce vibrations, it would be possible to use several paired ball tracks and ball seats. The center ball would impart rolling movement to all balls in contact with the ball race.

Abstract: An improved plate adapter for use with flexible couplings is disclosed which incorporates radially outwardly disposed pilot flanges for engagement with the hub and sleeve of the half coupling which pilot flanges are designed to form a pressfit relationship with the mating surfaces of the hub and sleeve. A suitable bolting arrangement is provided to aid in fitting of the adapter plate to the half coupling as well as to assist in removal of same. Additionally, the fastener arrangement enables fine adjustment of the radial runout of the sleeve of the half coupling relative to the axis of rotation of the shaft to which the half coupling is secured.