Abstract: A retention system for attaching a collar to a pipe. The collar has an internally-disposed groove configured for placement of a ring. The ring is sized such that in one orientation, it can enter the collar between torque-transmitting features into the internally-disposed groove. Once in the groove, the ring may be adjusted such that its aperture is generally aligned with the axis of the collar. In this orientation, the features retain the ring within the groove. A bolt and a pipe may then be placed within the collar from opposite sides. The bolt is attached to the pipe through the ring. Once joined, the collar is joined to the pipe, forming its box end. Such a retention system may be used to join a series of inner pipe members of a dual-member pipe assembly, as in horizontal directional drilling.

Abstract: An apparatus and method for preventing drill string drag. Rotation encoders are provided for tracking the rotation of an inner and outer member of a dual-member drill string. Based upon the drilling conditions, the readings of the encoder can detect when the inner member is dragging on the outer member. When such a drag condition is detected, a processor can trigger remedial measures, which may include increasing a rotation rate of the inner member, sending a warning signal, stopping operation, or a combination of these.

Abstract: A retention system for attaching a collar to a pipe. The collar has an internally-disposed groove configured for placement of a ring. The ring is sized such that in one orientation, it can enter the collar between torque-transmitting features into the internally-disposed groove. Once in the groove, the ring may be adjusted such that its aperture is generally aligned with the axis of the collar. In this orientation, the features retain the ring within the groove. A bolt and a pipe may then be placed within the collar from opposite sides. The bolt is attached to the pipe through the ring. Once joined, the collar is joined to the pipe, forming its box end. Such a retention system may be used to join a series of inner pipe members of a dual-member pipe assembly, as in horizontal directional drilling.

Abstract: A pipe assembly used in horizontal directional drilling operations. The pipe assembly has an outer member, an inner member, and first removable collar. The inner member has a polygonal outer profile of uniform shape along its length and is partially contained within the outer member. The first removable collar is supported on the inner member within the outer member and limits relative axial movement of the inner member and the outer member.

Abstract: An insert for installation on an inner pipe member of a dual-pipe member assembly. The insert is interposed between an external shoulder formed on the inner pipe member and an internal shoulder formed in an outer pipe member. Shoulder-to-shoulder impacts between pipe members results in wear to the insert, rather than to either pipe member. The insert has the shape of an unclosed loop and is positioned within an endless external groove formed in the inner pipe member.

Abstract: A bearing assembly having independently rotatable concentric inner and outer tubes. A bearing chamber containing multiple bearings is disposed between the tubes, allowing thrust but not rotation to be transferred between them. The bearing chamber is sealed from the inside of the inner tube. To prevent high pressure fluid from leaking from the inner tube to an exterior of the tool through the bearing chamber, damaging components, a flow path is formed. An annular piston responds to high pressure within the bearing chamber and the inner tube, opening a flow path from the inner tube to the environment.

Abstract: A connection system for a lid in a beacon housing. The lid is connected to the housing at a tab at a first end, after a lip of the lid is placed under a shelf at its second end. The tab has a cross-bore for receiving a connection pin through both the cross-bore and corresponding holes in the housing which form a continuous passage. The lid is placed under tension to reduce relative vibration between the lid and the housing. A set screw is placed within the tab to place a force on the connection pin. Further set screws are distributed about the lid and place the lid in tension relative to the housing. The lid can be removed by reducing the tension provided by the set screws, removing the connection pin, and adjusting the lid such that it is no longer under the shelf of the housing.

Abstract: A system for connecting a drill bit and pipe puller to a drill string. The system includes a downhole tool having an internal cavity and a through-hole in its wall. A coupler may be slidingly received in the cavity and connected using one or more fasteners which interconnect a groove in the coupler to the wall of the downhole tool. Fasteners used may be screws or bolts interconnecting the wall of the tool with radial holes in the coupler. Alternatively, bolts may interconnect the wall with a circumferential groove on the coupler. A drill bit may be threaded into the coupler. The coupler allows drill bits and other tools to be connected and disconnected from a downhole tool without unthreading the drill bit.

Abstract: A bearing assembly having independently rotatable concentric inner and outer tubes. A bearing chamber containing multiple bearings is disposed between the tubes, allowing thrust but not rotation to be transferred between them. The bearing chamber is sealed from the inside of the inner tube. To prevent high pressure fluid from leaking from the inner tube to an exterior of the tool through the bearing chamber, damaging components, a flow path is formed. An annular piston responds to high pressure within the bearing chamber and the inner tube, opening a flow path from the inner tube to the environment.

Abstract: A retention system for attaching a collar to a pipe. The collar has an internally-disposed groove configured for placement of a ring. The ring is sized such that in one orientation, it can enter the collar between torque-transmitting features into the internally-disposed groove. Once in the groove, the ring may be adjusted such that its aperture is generally aligned with the axis of the collar. In this orientation, the features retain the ring within the groove. A bolt and a pipe may then be placed within the collar from opposite sides. The bolt is attached to the pipe through the ring. Once joined, the collar is joined to the pipe, forming its box end. Such a retention system may be used to join a series of inner pipe members of a dual-member pipe assembly, as in horizontal directional drilling.

Abstract: A method for building a dual-member drill string comprising an inner drill string and an outer drill string. Inner pipe sections are connected using non-threaded connections, while outer pipe sections are connected using threaded connections. A new inner pipe section is rotated in a first direction until the inner pipe section applies torque to the existing inner pipe string. If the magnitude of the torque applied to the inner pipe string exceeds a pre-determined threshold value, the inner pipe section is automatically rotated in an opposite second direction. The inner pipe section rotates between opposite directions, once torque is sensed in each direction, until the inner pipe section is coupled to the inner pipe string.

Abstract: A system for connecting a drill bit and pipe puller to a drill string. The system includes a downhole tool having an internal cavity and a through-hole in its wall. A coupler may be slidingly received in the cavity and connected using one or more fasteners which interconnect a groove in the coupler to the wall of the downhole tool. Fasteners used may be screws or bolts interconnecting the wall of the tool with radial holes in the coupler. Alternatively, bolts may interconnect the wall with a circumferential groove on the coupler. A drill bit may be threaded into the coupler. The coupler allows drill bits and other tools to be connected and disconnected from a downhole tool without unthreading the drill bit.

Abstract: A retention system for attaching a collar to a pipe. The collar has an internally-disposed groove configured for placement of a ring. The ring is sized such that in one orientation, it can enter the collar between torque-transmitting features into the internally-disposed groove. Once in the groove, the ring may be adjusted such that its aperture is generally aligned with the axis of the collar. In this orientation, the features retain the ring within the groove. A bolt and a pipe may then be placed within the collar from opposite sides. The bolt is attached to the pipe through the ring. Once joined, the collar is joined to the pipe, forming its box end. Such a retention system may be used to join a series of inner pipe members of a dual-member pipe assembly, as in horizontal directional drilling.

Abstract: A system for connecting a drill bit and pipe puller to a drill string. The system includes a downhole tool having an internal cavity and a through-hole in its wall. A coupler may be slidingly received in the cavity and connected using one or more fasteners which interconnect a groove in the coupler to the wall of the downhole tool. Fasteners used may be screws or bolts interconnecting the wall of the tool with radial holes in the coupler. Alternatively, bolts may interconnect the wall with a circumferential groove on the coupler. A drill bit may be threaded into the coupler. The coupler allows drill bits and other tools to be connected and disconnected from a downhole tool without unthreading the drill bit.

Abstract: A system for connecting a drill bit and pipe puller to a drill string. The system includes a downhole tool having an internal cavity and a through-hole in its wall. A coupler may be slidingly received in the cavity and connected using one or more fasteners which interconnect a groove in the coupler to the wall of the downhole tool. Fasteners used may be screws or bolts interconnecting the wall of the tool with radial holes in the coupler. Alternatively, bolts may interconnect the wall with a circumferential groove on the coupler. A drill bit may be threaded into the coupler. The coupler allows drill bits and other tools to be connected and disconnected from a downhole tool without unthreading the drill bit.

Abstract: A bearing assembly having independently rotatable concentric inner and outer tubes. A bearing chamber containing multiple bearings is disposed between the tubes, allowing thrust but not rotation to be transferred between them. The bearing chamber is sealed from the inside of the inner tube. To prevent high pressure fluid from leaking from the inner tube to an exterior of the tool through the bearing chamber, damaging components, a flow path is formed. An annular piston responds to high pressure within the bearing chamber and the inner tube, opening a flow path from the inner tube to the environment.

Abstract: An insert for installation on an inner pipe member of a dual-pipe member assembly. The insert is interposed between an external shoulder formed on the inner pipe member and an internal shoulder formed in an outer pipe member. Shoulder-to-shoulder impacts between pipe members results in wear to the insert, rather than to either pipe member. The insert has the shape of an unclosed loop and is positioned within an endless external groove formed in the inner pipe member.

Abstract: A method for building a dual-member drill string comprising an inner drill string and an outer drill string. Inner pipe sections are connected using non-threaded connections, while outer pipe sections are connected using threaded connections. A new inner pipe section is rotated in a first direction until the inner pipe section applies torque to the existing inner pipe string. If the magnitude of the torque applied to the inner pipe string exceeds a pre-determined threshold value, the inner pipe section is automatically rotated in an opposite second direction. The inner pipe section rotates between opposite directions, once torque is sensed in each direction, until the inner pipe section is coupled to the inner pipe string.

Abstract: A pipe assembly used in horizontal directional drilling operations. The pipe assembly has an outer member, an inner member, and first removable collar. The inner member has a polygonal outer profile of uniform shape along its length and is partially contained within the outer member. The first removable collar is supported on the inner member within the outer member and limits relative axial movement of the inner member and the outer member.

Abstract: A bearing assembly having independently rotatable concentric inner and outer tubes. A bearing chamber containing multiple bearings is disposed between the tubes, allowing thrust but not rotation to be transferred between them. The bearing chamber is sealed from the inside of the inner tube. To prevent high pressure fluid from leaking from the inner tube to an exterior of the tool through the bearing chamber, damaging components, a flow path is formed. An annular piston responds to high pressure within the bearing chamber and the inner tube, opening a flow path from the inner tube to the environment.