Abstract: A universal joint assembly (12) includes a coupling hub member (26) and a female coupling member (24). The female coupling member (24) includes a receptacle (28) at one end for receiving a pivot end (30) of the coupling hub member (26). The joint (12) includes a central bearing structure (34) interposed between the coupling hub member (26) and female coupling member (24) for enabling the coupling members to pivot up to a maximum pivot angle with respect to each other about a coupling axis. The universal joint (12) also includes a plurality of torque transmitting rollers (50), each received in a different roller slot and spaced apart about the periphery of the coupling hub member (26) near its pivot end (30). The roller slots are formed on both the coupling hub member (26) and female coupling member (24) and enable the torque transmitting rollers (50) to transmit torque between the coupling members while rolling with respect to the roller surfaces as the coupling members pivot about the coupling axis.

Abstract: A navigable downhole drilling system incorporating a drilling motor having a system of sensors and information processors for determining the depth, inclination, direction and thrust of the drilling motor. Accordingly, the drilling operation can be continuously monitored and adjusted to ensure desired directional drilling. A programmed processor may be incorporated into the drilling system to guide the drilling motor along a predetermined course. A generator assembly provides power to the processors and sensors as a result of the precessional rotation of the rotor within the stator of the drilling motor. The overall length of the drilling system is minimized by piggybacking the thrust bearings with the power generation unit and siamesing the transmission assembly for the drilling motor with the power section of the motor. As a result, a downhole drilling system of navigable length is created which can be readily directed along the desired course.

Abstract: A power generation unit associated with a downhole drilling motor capable of producing sufficient rotational speeds to produce power for operating downhole devices associated with the drilling operation. The power generation unit takes advantage of the high speed precessional rotation of the rotor within the stator to drive the generator. The assembly includes a multi-lobed rotor displaceable within a stator using drilling fluid pumped therethrough. A crankshaft, mounted at one end concentric with the rotor and at its high speed take-off end concentric with the stator, transfers the rotor center precession to the shaft of the generator. In a preferred embodiment, the generator will include a socket for simply connecting downhole devices requiring electrical power.

Abstract: A composite stator construction for a downhole drilling motor which provides improved sealing and distortion properties. The elastomer which maintains the sealing/pumping action of the motor is applied in a uniform thickness to a rigid metallic form. In the stator, the rigid former has the basic configuration of the stator and is mounted within the casing of the motor. In the rotor, the elastomer can be applied directly to a metallic rotor core. The basic geometry is provided by the metallic former thereby reduces distortion of the lobes under increased torsional forces.

Abstract: A selectively adjustable double bend positive positioning directional drilling system for kickoff from a main well bore to change the directiion of drilling. The tool is selectively adjustable to facilitate running into the vertical well bore and subsequently to provide an aggressive build rate upon kickoff. The tool string incorporates a pair of kickoff pads--a lower fixed pad and an upper rotatively adjustable pad. As the tool is run into the well bore the adjustable pad is oriented away from the bend in the motor housing. Once in the hole, the string would be rotated relative to the adjustable pad by the reactive torque of the downhole motor and locked in the desired orientation. The adjustable pad incorporates an internal slot system to guide rotation and lock the pad in position. Alternatively, a single arm underreamer-type assembly could be used as the upper kickoff pad.

Abstract: A geothermal wellhead repair unit including a mechanically set packer to isolate the wellhead for removal and repair thereof. The packer is run into the well string using a running tool. The packer is set by placing tension on the mandrel to set the packing elements and the slip assembly. Once the packer is set, the running tool can be disengaged without fear of collapsing the packer and the wellhead removed for repair or replacement. Upon replacement of the wellhead, the running tool can be used to unset and retrieve the packer.

Abstract: A geothermal wellhead repair unit including a mechanically set packer to isolate the wellhead for removal and repair thereof. The packer is run into the well string using a running tool. The packer is set by placing tension on the mandrel to set the packing elements and the slip assembly. Once the packer is set, the running tool can be disengaged without fear of collapsing the packer and the wellhead removed for repair or replacement. Upon replacement of the wellhead, the running tool is used to unset and retrieve the packer.

Abstract: A geothermal wellhead repair unit including a mechanically set packer to isolate the wellhead for removal and repair thereof. The packer is run into the well string using a running tool. The packer is set by placing tension on the mandrel to set the packing elements and the slip assembly. Once the packer is set, the running tool can be disengaged without gear of collapsing the packer and the wellhead removed for repair or replacement. Upon replacement of the wellhead, the running tool can be used to unset and retrieve the packer.

Abstract: A mud saver valve for insertion within the drill string to retain mud in the drill pipe and prevent the mud column from flowing past the valve when pumping is interrupted. The valve body has a tubular body and a piston having an axial passage for the flow of drilling mud. This piston is biased within the body by a spring and axially movable in response to the mud flow. A check valve plug is disposed within the bore which may be removed to run wireline tools. The plug is seated within a reduced diameter portion of the body and includes a replaceable inner sleeve which engages the piston to prevent flow through the valve. The inner sleeve is replaced as it becomes worn due to the erosive forces of the drilling mud.

Abstract: A mud saver valve for insertion within the drill string to retain mud in the drill pipe preventing the mud column from flowing past the valve when pumping is interrupted. The mud saver valve includes an internal check valve which permits increased flow of mud upward through the valve when a predetermined downhole pressure is reached. The increased flow of the check valve prevents a blow-out of the plug spear in the event sudden upward pressure is encountered. The check valve forms a part of the plug spear which is removable from the mud saver valve to facilitate the running of wireline tools.

Abstract: A thermal jacket shield for a drilling motor which permits drilling operations in high temperature wells without failure of the motor. The thermal shield includes a multiple passageway casing to shroud the motor and through which is circulated drilling fluid used to operate the drilling motor. The motor is positioned within concentric inner and outer shells which form a fluid annulus through which the fluid is circulated. An intermediate housing sub connected to the lower end of the drilling motor includes a nozzle through which a controlled quantity of drilling fluid is passed into the annulus formed by the inner and outer annular shells. Outlet ports in the outer shell allow the drilling fluid to flow to the exterior of the tool. As a result, cooling fluid is continuously passed through the jacket shield to maintain the operating temperature of the motor at an acceptable temperature.

Abstract: A detonation assembly for an explosive wellhead severing system which employs a battery pack lowerable through a drill string to engage and power the detonation assembly positioned within the well bore. The lowerable unit includes a biased shutter which seals the contacts from discharge of the battery pack by the surrounding fluids. The shuttered unit is lowered into contact with the receiving unit to arm the detonation assembly. Until the power unit is lowered into engagement, the severing system is not armed. In case of malfunction or misfire, the power unit can be retrieved to disarm the detonator assembly. The entire assembly is housed within the drill string to isolate the critical elements from the surrounding environment.

Abstract: A drill string apparatus for the controlled absorption of both axial and torsional forces exhibited on the well string during drilling operations. The device is adapted to be connected in the drill string above the drilling tool in order to control the forces acting on the bit and to arrange the mean weight on bit for the selected drilling operation. Generally, the apparatus includes an outer casing coupled at its upper end to the drill string and an inner assembly telescopically received within the outer casing and connected at its lower end to the lower part of the bottom hole assembly or the drilling tool. Rotational torque is transferred from the drill string and outer casing to the inner assembly and drill bit by a series of helical splines. The mean weight on bit is controlled through an interchangeable pressure control nozzle mounted at the top of the inner assembly.

Abstract: An underreamer including a body having a bore therethrough, an arm mounted at its upper end to the body, a sleeve member detachably secured to the lower end of each arm and adapted to receive the frictional wear caused by the rotation of the conical cutter mounted thereto. Bearings and seals disposed between the cutter and the sleeve member provide smooth rotation of the cutter. In addition, locking pins and bearings extending between the arm and the sleeve member secure the sleeve on the arm. The arms are pivotally mounted in slots in the body and mechanical structure is provided for moving the arms to their cutting position with their lower ends positioned radially outward from the body.

Abstract: A seal element for oil well tools, such as drilling cutters and roller reamers, which allows the drilling media to permeate into the bearing system of the cutter to cool and lubricate the internal mechanism. The seal element is adapted to control the particle size of contaminants flowing into the bearing system by filtering the drilling media. The bearings act as agitators during operation of the cutter to promote fluid motion through the bearing system. The seal and lubrication system may be utilized as a back-up to the conventional lubrication supply or as supplemental lubrication.

Abstract: A packing assembly for a whipstock in which the whipstock can be run into a well casing to a level above the bottom and milling through the casing wall without having to make a round trip with the well string. The packing assembly includes slip-type anchors which initially set the assembly and packing elements which sealingly engage the well casing to seal off the casing while anchoring the device. Disposed between the packing elements is a spacer ring which is axially movable in response to the fluid pressure within the well casing to enhance the sealing engagement of the packing elements. The spacer ring includes an O-ring seal which provides improved sealing between the spacer ring and the inner mandrel to which it is mounted. In order to compress the packing elements while preventing extrusion thereof, an overleaf ring and retainer arrangement is provided thereby enhancing sealing engagement of the packing assembly.

Abstract: A method and apparatus for setting an underwater conductor pipe in which the conductor pipe is lowered into the wellhole on a drill string as the borehole is being formed by a drill bit and underreamer positioned at the end of the drill string below the end of the conductor pipe. The drill string and conductor pipe are detachably interconnected by a housing latch which includes means for detachably securing the drill string and drilling assembly to the conductor pipe. The drill string is provided with an upper latch sub, which retains and supports the drill string in its fully extended position within the conductor pipe, and a lower latch sub which retains and supports the drill string in the retracted position. As the apparatus is lowered a drill motor actuates the drilling assembly such that the well hole is formed in the ocean floor. Drilling continues until the permanent guide base of the conductor pipe engages the ocean floor.

Abstract: A drilling head with an upper body assembly removably clamped onto a stationary spool via a bayonet-type coupler clamp rotated into clamped and unclamped positions by a remote controlled hydraulic motor connected to the clamp by a ring and pinion gear. The upper body assembly has a kelly bushing, a corrugated drive bushing rotatable with the kelly bushing, a drive ring rotatable with the drive bushing a bearing assembly surrounding the drive ring, and an elastomeric stripper connected to the drive ring for rotation therewith. The stripper is adapted for sealing engagement with a rotating kelly drive which slides down through the drilling head. Quick connect/disconnect lubrication fittings on the clamp and upper body assembly are releasably mated upon rotation of the clamp to the clamped position to provide lubrication from a single lubrication line to both the bearing assembly and seals via passageways formed in the outer body of the upper body assembly.