Abstract: An apparatus for gripping a down hole tubular for support and rotation, or a string of such tubulars, includes a body element adapted to be rotated at high torques either by a top head drive or a rotary table of an earth drilling machine. Gripping elements are mounted in a central cavity of the body element, and each gripping element includes a lower gripping portion shaped to engage a tapered shoulder of a length of drill pipe to support the drill pipe and an upper gripping portion shaped to engage the tool joint of the drill pipe to rotate the drill pipe. First guides are secured between the body element and the lower gripping portions in the central cavity, and these first guides are oriented to approach one another toward a lower portion of the body element. Second guides are secured between the upper and lower gripping portions, and these second guides are oriented to approach one another at an acute angle with respect to the axis.

Abstract: An earth drilling machine of the type having a boom mounted adjacent a mast to move a tubular between a lower, horizontal boom position and an upper, vertical boom position also includes a lifter configured to move a length of downhole tubular between a lower lifter position aligned with a tubular storage device and an upper lifter position aligned with the lower boom position. An automatic sequencing system includes multiple position sensors responsive to the position of at least the boom, the lifter and a length of downhole tubular at selected positions. A sequencing system is responsive to the position sensors for automatically coordinating movement of the lifter and the boom to reduce or eliminate delays occasioned by tubular handling.

Abstract: A lifting device for down hole tubulars is used with an earth drilling machine of the type having a boom for moving a down hole tubular from a horizontal position at an intermediate level to a raised position aligned with a drilling axis, and a tubular holding device for holding a down hole tubular horizontally at a lower level, beneath the intermediate level. The lifting device includes first and second spaced, parallel tracks oriented to extend substantially from the lower level substantially to the upper level and first and second dolleys, each guided for movement along a respective one of the tracks and configured to retain the down hole tubular. The dolleys are moved between the lower and intermediate levels by an actuator which is connected to both of the dolleys by a mechanical linkage which includes tension members. This mechanical linkage positively synchronizes movement of the dolleys along the tracks to maintain the tubular horizontal as it is moved between the lower and intermediate levels.

Abstract: A feeding device for down hole tubulars includes a frame which defines a support surface. First and second stops are arranged to reciprocate in stop guides between an upper position, in which the stops interrupt movement of a tubular, and a lower position in which the stops allow movement of the tubular. The stop guides are moveable relative to one another to adjust the separation between the stops as appropriate for tubulars of different diameters. A tilting actuator arm cycles the stops between upper and lower positions to control the feeding of tubulars along the support surface.

Abstract: A centering spinner for centering and spinning down hole tubulars having a range of diameters. The centering spinner includes a frame capable of admitting a down hole tubular therein and a plurality of roller assemblies pivotally coupled to the frame to converge upon and center the down hole tubular. According to a further feature, adjacent rollers of the roller assemblies of the centering spinner are axially displaced with respect to a down hole tubular retained therein.

Abstract: An apparatus for gripping a down hole tubular for rotation in a drilling machine includes a support member adapted for connection to the quill of the drilling machine. The support member supports three or more guides which converge toward one another in a selected direction. A clamping dog or engaging member is mounted to slide in each of the guides to move into engagement with a down hole tubular when positioned toward a first end of the guide and out of engagement with the down hole tubular when positioned toward a second end of the guide. A linkage interconnects the engaging members, and includes an acutating member exposed at an upper portion of the support member. This actuating member moves vertically along an axis between open and closed positions, which causes the engaging members to release or engage the tubular.

Abstract: Compact casing tongs include a tube which is secured to a connector, the connector in turn being supported and rotated by a quill of a top head drive assembly. The lower end of the tube regidly supports a set of cams which define multiple recesses. A jaw is mounted in each recess, and each of the jaws is connected to a brake ring positioned outside the tube. By externally braking the brake ring while the quill connector body is rotated the jaws are shifted out of the recesses to grip the exterior of a casing positioned within the tube. The tube is dimensioned to ensure that the jaws engage the body of the casing beneath the upper collar of the casing.

Abstract: An earth drilling machine includes a crown block assembly, a travelling block assembly and a drawworks. The drawworks includes a drum which rotates about a drum axis. The drum axis is oriented at right angles to a fast line plane defined by a fast line sheave included in the crown block assembly. In this way, the fleet angle between the drum and the fast line sheave is kept substantially equal to zero. Various sheave arrangements are described which combine proper selection of sheave pitch diameter, sheave axis angle, and sheave placement to ensure that the fleet angle of all of the sections of line extending between the crown block assembly and the travelling block assembly are reeved with a fleet angle exactly equal to zero. In this way line wear is reduced and the height, weight and windage of the mast are all minimized.

Abstract: A top head drive cooling system is provided for an earth drilling machine of the type having a mast, a top head drive assembly mounted for movement along the mast, a quill included in the top head drive assembly, and an electric motor for rotating the quill. This cooling system includes an air duct mounted to the mast and defining a slot extending along the mast. The slot is sealed by a pair of flexible resilient lips which bridge the slot, and a blower is situated at ground level to blow cooling air into the air duct. A conduit is provided on the top head drive assembly, and the conduit extends between the lips into the air duct and conducts air from the air duct to the electric motor. The portion of the conduit which extends into the air duct is preferably tapered at both ends in order to provide a sliding seal against the lips. A position measuring system is coupled to the conduit and is positioned within the air duct.

Abstract: A drilling machine includes a drilling substructure skid which defines two spaced parallel skid runners and a platform. The platform supports a draw works mounted on a draw works skid, and a pipe boom is mounted on a pipe boom skid sized to fit between the skid runners of the drilling substructure skid. The drilling substructure skid supports four legs which in turn support a drilling platform on which is mounted a lower mast section. The legs are pivotably mounted both at the platform and at the driling substructure skid and a pair of platform cylinders are provided to raise and lower the drilling platform. A pair of rigid, fixed length struts extend diagonally between the platform and the substructure skid away from the platform such that the struts do not extend under the platform and obstruct access to the region under the platform. Preferably, the pipe boom skid mounts a pipe boom as well as a boom linkage, a motor, and a hydraulic pump adapted to power the pipe boom linkage.

Abstract: A top head drive assembly for a drilling machine includes a wrench assembly used to make up and break out threaded connections. This wrench assembly is mounted for axial movement on rails of the top head drive assembly, and is positioned immediately under the quill. The top head drive assembly also includes a tubular support assembly which includes slip type inserts for supporting a string of down hole tubulars. This support assembly can be pivoted out of alignment with the drilling axis or can be locked in alignment with the drilling axis. A plurality of centering elements are mounted under the support assembly and are movable to center the upper end of a tubular for insertion into the tubular support assembly. Preferably, both the top head drive assembly load beam and the support beam of the support assembly are formed of box sections having converging side plates and internal diagonal brace plates which transmit downward forces on the beam into forces tending to cause the side plates to diverge.

Abstract: A top head drive assembly includes a tubular quill having a central passageway aligned with an axis. The quill is supported for rotation on a load beam included in the top head drive assembly such that the quill is movable along the axis through a range of travel sufficient to provide thread protection to the down hole tubulars during tubular handling operations. Splines drivingly connect the quill with a transmission such that the transmission is operative to rotate the quill throughout the range of travel of the quill along the axis. A blowout preventer valve is mounted in an upper part of the quill to move axially and rotationally with the quill in order to eliminate sliding or rotary seals between the blowout preventer valve and the drill string.

Abstract: An internal wrench for an earth drilling machine of the type having a mast, a top head drive assembly mounted for movement along the mast and a quill rotated by the top head drive assembly includes a body having an upper end and a lower end sized to fit within a length of casing. The upper end of the body is mounted to the quill for rotation with the quill and several jaws are mounted to the lower end of the body to move between an extended position in which the jaws engage in interior surface of the casing to rotate the casing with the body, and a retracted position in which the jaws are out of engagement with the interior surface. The jaws are selectively moved between the extended and retracted positions in response to rotation of the body by a system which includes a drag ring which operates the jaws and a friction brake which engages the drag ring. A plug is mounted to an intermediate portion of the body to mate with threads at the upper end of the casing to seal off the casing.

Abstract: A drilling machine includes a drilling substructure skid which defines two spaced parallel skid runners and a platform. The platform supports a draw works mounted on a draw works skid, and a pipe boom is mounted on a pipe boom skid sized to fit between the skid runners of the drilling substructure skid. The drilling substructure skid supports four legs which in turn support a drilling platform on which is mounted a lower mast section. The legs are pivotably mounted both at the platform and at the drilling substructure skid and a pair of platform cylinders are provided to raise and lower the drilling platform. A pair of rigid, fixed length struts extend diagonally between the platform and the substructure skid away from the platform such that the struts do not extend under the platform and obstruct access to the region under the platform. Preferably, the pipe boom skid mounts a pipe boom as well as a boom linkage, a motor, and a hydraulic pump adapted to power the pipe boom linkage.

Abstract: A drilling apparatus of the type having a drilling mast and a transfer arm mounted at a first axis adjacent the mast to move between a lower position near ground level and an upper position aligned with the mast is provided with a reaction point anchor fixed with respect to the drilling mast and spaced from the first axis. A fixed length link is pivotably mounted to the transfer arm at a second axis, spaced from the first axis, and a first single stage cylinder is pivotably mounted at one end to the distal end of the link and at the other end to the transfer arm. A second single stage hydraulic cylinder is pivotably mounted at one end to the distal end of the link and at the other end to the reaction point.

Abstract: An elevator for drill pipe which includes at least two jaws for supporting a length of pipe and structure for maintaining the jaws in clamping engagement with the pipe. The structure includes linkage means coupled to the jaws for maintaining the jaws clamped to the pipe when the elevator and pipe are urged apart by gravity due to the weight of the pipe as when the pipe is raised or otherwise supported by the elevator. Additionally or alternatively, the elevator includes a pressure actuator assembly connected to the jaws for applying a positive force against the jaws for maintaining the jaws clamped to the pipe independent of the effect of gravity and, thus, independent of the orientation of the elevator.