Abstract: A rock drill apparatus has features that allow it to be attached to a conventional impact tool. The rock drill attachment has a housing that is secured to the impact tool carriage below the hammer of the impact tool. A tappet is carried in the housing of the rock drill attachment for axial movement in response to blows from the hammer. The tappet is nonrotatable with respect to the housing and is adapted to deliver blows to a tool shank. A conversion device is coupled between the tappet and the tool shank to convert downward movement of the tappet into rotation of the tool shank prior to the impact of the tappet on the tool shank. A spring moves the tappet away from the tool shank after impact for repeating the cycle. The conversion device includes a sleeve with inclined splines that engage inclined splines on the tool shank. A clutch locks the sleeve to the tappet during downward movement to rotate the tool shank. During upward movement, the clutch allows the sleeve to rotate with respect to the tappet.

Abstract: An improvement in blowout preventer apparatus of the type having a radially compressible annular packing mounted within a housing chamber, the housing having axially aligned upper and lower conical bores communicating with an inner bore of the annular packing, the packing axially expanding towards said upper and lower bores upon said radial compression, a plurality of rigid end ring segments attached to sectored webs of the ends of the packing and thereby individually movable axially outwardly and radially inwardly relative to the upper and lower conical bores to control the packing axial expansion during radial compression of the packing has keying means cooperating with the rigid end ring segments of the packing and the conical bores for guiding a sector-wise movement of the segments in individually separate and predetermined paths along the conical bores to a common radial position independent of the uniformity of the packing radial compression and/or axial expansion.

Abstract: Disclosed is a well packer for releasable setting within a well conduit, including a seal assembly for sealing the packer to the conduit and an anchor assembly for anchoring the packer to the conduit. The packer is set in stages by hydraulic pressure. The seal assembly is extended, and locked, in sealing configuration; the anchor assembly is then set, and locked, in gripping engagement with the conduit. The packer is released by longitudinal movement of a central mandrel relative to the seal and anchoring assemblies. The release of the packer also occurs in stages, with the seal assembly unlocked and released from its set configuration followed by like operations relative to the anchor assembly. A hold-down system prevents premature release of the packer by securing the mandrel against such relative longitudinal movement.

Abstract: An oil well blowout preventer includes a radially compressible annular packing having radially-sectored end portions in a housing having axially aligned upper and lower bores communicating with the inner bore of the packing and with the sectored ends, and also includes hydraulic means for radially constricting the packing, thereby causing it to axially expand. A plurality of circumferentially-arranged rigid wedge members carried by the sectored end portions are individually movable radially into the bores to control the axial expansion whereby radial sectors of the packing may move sequentially inward to effect a seal between the upper and lower bores in response to progressive axial expansion of the packing as the packing undergoes nonuniform sector-wise radial compression. The inward radial movement of the rigid members are limited by stops to a common radial position independent of the uniformity of the radial compression.

Abstract: A depth determining device has features for informing the operator of the depth of the cutting tool of a hydraulic drilling machine. The drilling machine is for earth boreing and has a piston carried in a cylinder and secured to a driven kelly. The device has a transducer mounted at the top of the cylinder for transmitting a sound wave through hydraulic fluid to the tap of the piston and detecting the return of the wave at the top of the cylinder. A counter determines the elapsed time for the sound travel. The elapsed time is converted into depth and displayed.

Abstract: Disclosed herein is an earth boring bit of otherwise conventional construction except for the bearing and cutter retention. A snap ring is used to retain the cutter, the grooves that receive the ring and the ring construction being such that the ring is forced into the retainer groove when the cone is thrust inward. The ring cannot therefore accidentally return to its assembly position to permit cutter loss. This enables the use of exclusively frictional bearings and retainer means of exceptional strength and reliability.

Abstract: An earth boring drill bit has staggered rows of wear resistant inserts that are positioned to provide more inserts in the rows without sacrificing insert supporting metal. The staggered rows include a first or heel row of inserts that is positioned next to the gage surface of the cutter. The second or adjacent row is located farther from the gage surface and staggered with the first row so that the first and second row inserts alternate in contacting the bottom of the borehole. Each insert has a centerline that intersects the cutter axis. The first row inserts intersect the cutter axis at a greater angle than the second row inserts. This positioning results in a more uniform section of metal between the holes of the first and second row inserts, enabling a closer spacing.

Abstract: A hydraulically operated earth boring machine, improved with a flowmeter and indicator to show the instantaneous and the greatest depth of the drilling tool.

Abstract: Disclosed is a system including two or more fluid pressure piston-and-cylinder assemblies. The cylinders are linked in pairs so that retraction of both piston rods reduces the length of the pair of assemblies to the length of a single assembly. Operation of both pistons in a pair provides an effective stroke twice the length of a single assembly stroke. In a particular embodiment, a double cylinder system is used as a pickup system for elevating equipment along a mast in a well workover rig.

Abstract: An annulus valve apparatus integrated within a tubing hanger controls fluid flow through a tubing-casing annulus formed between a casing and a tubing string located within and generally concentric to the casing and connected to the tubing hanger. The tubing hanger is landed within the casing and sealing relation thereto and divides the annulus into an upper and lower portion. Fluid flow passages located within the hanger body communicate between the portions of the annulus above and below the hanger. An annulus opening means, mounted to the hanger body, allows fluid to pass between the fluid flow passages and the portion of the annulus below the hanger. The opening means is spring biased to close the passages to fluid flow. A plurality of control fluid passages in the hanger body communicate between the opening means and the hanger bore, which is aligned with the tubing bore, and pass a hydraulic control fluid from the hanger bore to the opening means.

Abstract: A seal assembly releasing tool is shown having an outer support case and an inner unlocking element rotatably mounted on a shaft and coupled by a planetary gear train. The seal assembly is provided with cam surfaces into which cam followers latch for securely connecting the tool to the seal assembly and enabling the outer case to turn the assembly in one direction while the inner element turns the locking sleeve of the seal assembly in the other direction to release the seal assembly.

Abstract: An earth boring drill bit, particularly for large diameter shafts, has a cutter assembly with improved bearing and seal arrangement and an improved cutting insert arrangement. A cutter assembly has an axle with an enlarged central portion and reduced portions on both sides. A cutter sleeve is carried on bearings by the central portion of the axle. An annular member with a central bore is secured to each side of the cutter sleeve. A metal face seal is secured between the reduced portion and the central bore on each side. The cutter contains rows of hard metal inserts secured in holes in the exterior. To reduce tracking, the inserts within a row are separable into groups with varied pitch within each group. The groups cycle with two groups having a gradual increase in pitch and two groups having decreasing pitch.

Abstract: An earth boring drill bit has a drilling fluid nozzle with features that protect the nozzle retaining ring from erosion and avoid pressing cracks. The drill bit has a passage with at least one outlet and a nozzle located at the outlet for discharging fluid. The nozzle has a shell mounted in the outlet and retained by a retaining ring. An insert is bonded inside the shell. The insert is of tungsten carbide or ceramic for resisting erosion. The insert has an extended portion that extends below the rim of the outer member for protecting the retaining ring from flowing drilling fluid.

Abstract: A downcrowding device for an earth boring apparatus has an improved take-up device for taking up slack in the downcrowding cable. The downcrowding device is of the type having a rotatable drum, hydraulic rams for moving the drum downwardly, a brake for preventing rotation of the drum while moving downwardly, and a downcrowding cable that is connected directly to the top of the kelly and wrapped around the drum. The take-up device includes a take-up sheave that is suspended from the mast. A take-up cable is wrapped around the drum for rotating the drum in the opposite direction to the downcrowding cable. The take-up cable is reeved over the take-up sheave and is connected to the top of the kelly. The cable tensioner is located between the mast and the take-up sheave for allowing the sheave to move downwardly with respect to the mast as the kelly and drum move downwardly during drilling.

Abstract: Disclosed herein is a large diameter earth boring bit with improved nozzle placement. The bit is of the type having a cutter support with several rotatable cutters mounted below. The bit is connected to a string of pipe having an input and a return flow passage. Nozzles are located on the cutter support for the discharge of fluid onto the borehole bottom to sweep cuttings into an intake port in the cutter support. An outer zone nozzle is located at the periphery of the cutter support for cleaning the gage area of the borehole.Several inner zone nozzles are spaced between the periphery and the intake port. The inner zone nozzles are positioned so that the area of influence of each nozzle overlaps with its next inward nozzle. This creates a continuous stream that entrains cuttings and sweeps them to the intake.

Abstract: A stabilizer for attachment to drill string in large diameter earth boring or shaft drilling to center the drill string and maintain alignment of the drill bit. The stabilizer has an inner hub that is rigidly secured to the drill string above the bit. A rubber tube inside the inner hub is compressed to lock the inner hub to the drill string. An outer hub encircles the inner hub. A bearing is mounted between the inner hub and outer hub to allow rotation with respect to each other. The bearing includes a frusto-conical ring in contact with individual pads that are exposed to the drilling fluid. A number of arms extend radially outward from the outer hub to centralize the drill string. The arms are telescopingly received in the outer hub and are pinned together by tie bars at their outer ends to allow them to be quickly removed.

Abstract: An improved pressure compensator for earth boring drill bits for minimizing the pressure differential between the lubricant and the well bore. A flexible diaphragm is located in the lubricant reservoir for separating the lubricant from the borehole fluid. The diaphragm is positioned in the reservoir so that a substantial void space exists on the borehole fluid side of the reservoir. A retainer holds the diaphragm in this position, requiring a positive lubricant pressure to stretch the diaphragm in order to fill the void space. For lubricating the bit, the lubricant is introduced under pressure sufficient to stretch the diaphragm. The lubricant pressure is then released, allowing the compensator to return to its original shape which in turn causes the excess lubricant to be expelled. This assures complete filling and a desired void space.

Abstract: A hydraulic mast digger has a kelly head with improved retaining and sealing features. The digger is of the type having a kelly with a bearing assembly mounted between the kelly and a bearing sleeve. The bearing sleeve is reciprocally carried in the hydraulic cylinder and moves in response to hydraulic fluid pressure. The bearing assembly allows rotation of the kelly with respect to the bearing sleeve. A cap is secured by threads to the bearing sleeve above the top of the kelly to define a piston. The cap has an upwardly facing shoulder located below the upper edge of the bearing sleeve. A retainer is rigidly secured to the cap and extends down into the space between the cap and bearing sleeve. A locking device locks the retainer to the bearing sleeve. Preferably the locking device includes a key that fits within slots formed on the retainer and bearing sleeve. A primary seal encircles the retainer.

Abstract: An impact tool for mining, demolition work and the like. An energy storing device such as a coil spring, when compressed, accelerates a hammer to deliver a blow to a working tool. The hydraulic cocking mechanism has a compression chamber and a bias chamber. A shaft extends through the compression chamber and into the bias chamber. The shaft has an annular stop attached to it and reciprocally carries a compression sleeve above the annular stop. A bias member extends into the bias chamber. Input hydraulic pressure urges the bias member to press the compression sleeve into seating contact with the annular stop to define a piston. Hydraulic input pressure acting at the same time below the piston urges the shaft upward to cock the spring. At the top of the stroke, ports and passages reduce the pressure difference above and below the piston to allow the spring to force the shaft down for impact. On the downstroke, the compression sleeve and annular stop separate.

Abstract: An earth boring drill bit for large diameter shafts has an improved cutter arrangement. The drill bit has a cutter support member with a number of cutters mounted to it for disintegrating the earth formation face. At least one inner cutter is mounted near the center for cutting the center area. A number of gage cutters are mounted at the periphery to cut the gage area of the shaft. A number of intermediate cutters are spaced between the inner and gage cutters. Each intermediate cutter overlaps one-half of its width with an adjacent intermediate cutter.