A bumper spring assembly having a one piece mandrel including an integral head piece is further configured with a cage assembly retained on the mandrel with a cage nut locked to the mandrel to obviate the need for pins, set screws, and the like, to provide a more robust assembly. In two embodiments the cage nut is locked to the mandrel in a swaging operation. Improved flow of fluids through and around the bumper spring assembly are also provided.

A bumper spring assembly having a one piece mandrel including an integral head piece is further configured with a cage assembly retained on the mandrel with a cage nut locked to the mandrel to obviate the need for pins, set screws, and the like, to provide a more robust assembly. In two embodiments the cage nut is locked to the mandrel in a swaging operation. Improved flow of fluids through and around the bumper spring assembly are also provided.

Embodiments of a perforating gun assembly for use in a wellbore are disclosed herein. In one embodiment, the perforating gun assembly includes at least a tubular carrier gun body having an outer diameter, an inner diameter, and a threaded portion extending a distance (d) along an outer surface and proximate an uphole end thereof; and a swell sleeve located radially inside of the tubular carrier gun body, the swell sleeve extending along at least 90% of the distance (d).

Embodiments of a perforating gun assembly for use in a wellbore are disclosed herein. In one embodiment, the perforating gun assembly includes at least a tubular carrier gun body having an outer diameter, an inner diameter, and a threaded portion extending a distance (d) along an outer surface and proximate an uphole end thereof; and a swell sleeve located radially inside of the tubular carrier gun body, the swell sleeve extending along at least 90% of the distance (d).

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.

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.

There is disclosed a threaded joint for coupling together rods, tubes, pipes etc. The joint consists of helical box and pin thread segments each defined by a pressure flank and a clearance flank spaced apart from each other with alternating roots and crests. The pressure flank is defined by an S-curve extending between the root and the crest, which is defined by a first curvature c1 adjacent to the root and a second curvature c2 adjacent to the crest. c1 and c2 curve in opposing directions with an inflection point “i” between curvatures c1 and c2.

There is disclosed a threaded joint for coupling together rods, tubes, pipes etc. The joint consists of helical box and pin thread segments each defined by a pressure flank and a clearance flank spaced apart from each other with alternating roots and crests. The pressure flank is defined by an S-curve extending between the root and the crest, which is defined by a first curvature c1 adjacent to the root and a second curvature c2 adjacent to the crest. c1 and c2 curve in opposing directions with an inflection point “i” between curvatures c1 and c2.

A system for blocking rotation between a first tubular and a second tubular includes a key positioned within a recess formed in the first tubular. The system also includes a retention fastener securing the key to the first tubular, the retention fastener being arranged within an elongated aperture extending through the key. The system further includes an installation fastener moving the key from a storage configuration when in a first position to an engaged configuration when in a second position, the installation fastener having a tapered face that engages at least a portion of the key. The system also includes teeth arranged along a bottom portion of the key, proximate the second tubular, the teeth engaging the second tubular via rotation of the key about the retention fastener and blocking rotation of the first tubular relative to the second tubular in a first direction.

A system for blocking rotation between a first tubular and a second tubular includes a key positioned within a recess formed in the first tubular. The system also includes a retention fastener securing the key to the first tubular, the retention fastener being arranged within an elongated aperture extending through the key. The system further includes an installation fastener moving the key from a storage configuration when in a first position to an engaged configuration when in a second position, the installation fastener having a tapered face that engages at least a portion of the key. The system also includes teeth arranged along a bottom portion of the key, proximate the second tubular, the teeth engaging the second tubular via rotation of the key about the retention fastener and blocking rotation of the first tubular relative to the second tubular in a first direction.