Abstract: The invention concerns a method for casing a borehole which consists of successively lowering an unlimited plurality of strings of casing having a common diameter, the next one through the preceding one, to be installed one beneath the other and being sealingly connected. Thus a next casing (6) is lowered folded through the preceding casing (5) and the expansion process consists either in injecting pressurized fluid through the drillstring (54) towards the next casing (6) so as to re-inflate it, or the next casing (6) is a cylindrical pipe having a diameter smaller than the internal diameter of the preceding casing (5) and the expansion process consists in forcing a cylindrical gauge (52) from the top end (26) to the bottom bell (28) of the next casing (6) so as to increase its diameter to make it equal to the diameter of the preceding casing (5). The method can use a cementing shoe (34) and a metal-to-metal seal (29) between the casing string.

Abstract: A tubing hanger suspension assembly for an oil and gas well completion system and a method of installing same. The tubing hanger suspension assembly includes a tubing hanger housing which is positioned in the wellhead housing. The tubing hanger assembly includes a sealing and lockdown mechanism capable of providing sealing and load support of the production tubing in the production casing string. A stab sub assembly connected to the upper end of the tubing hanger suspension assembly and lower end of the Christmas tree assembly provides downhole hydraulic and electric functionality and annulus access to the production tubing.

Abstract: The present invention generally provides apparatus and methods for reducing the pressure of a circulating fluid in a wellbore. In one aspect of the invention an ECD (equivalent circulation density) reduction tool provides a means for drilling extended reach deep (ERD) wells with heavyweight drilling fluids by minimizing the effect of friction head on bottomhole pressure so that circulating density of the fluid is close to its actual density. With an ECD reduction tool located in the upper section of the well, the friction head is substantially reduced, which substantially reduces chances of fracturing a formation.

Abstract: A spearhead assembly (10) comprises a base (12) provided with a slot (14) at one end (16) which opens onto an outer surface (13) of the base (12). The outer surface (13) is composed of three contiguous surface portions (18, 20 and 22). A spearpoint (20) is pivotally coupled at its proximal end (26), which is disposed in the slot (14), to the base (12). A distal end (28) of the spearpoint (24) extends or projects beyond the slot (14) and the surface (13) of the base (12). A spearpoint positioning system (30) urges the spearpoint (24) toward one of three annually spaced positioned. These positions are characterised by the spearpoint (24) extending substantially perpendicular to parallel opposed edges of the slot (14) which open onto, or are flanked by, the surface portions (18), (20 and 22). Moving the spearpoint from one position to another requires the application of an external force.

Abstract: A controller for a pump for pumping a drilling fluid from a storage unit to a downhole tool includes at least one actuation device coupled to a control console of the pump, and at least one connector coupled to the at least one actuation device and a pump control mechanism of the control console.

Abstract: Solutions for the propagation of a hydraulic fracture in a permeable elastic rock and driven by injection of a Newtonian fluid. Through scaling, the dependence of the solution on the problem parameters is reduced to a small number of dimensionless parameters.

Abstract: Embodiments of the present invention generally provide a more reliable variable choke flow control valve. In one embodiment, a variable choke valve for use in a wellbore is provided. The valve includes a tubular housing having an axial bore therethrough and a port through a wall thereof. The valve further includes a tubular sleeve having an axial bore therethrough and first and second holes through a wall thereof and disposed within the housing. The first hole is larger than the second hole, and the sleeve is actuatable among three positions: a first position where the first hole is aligned with the port, a second position where the second hole is aligned with the port, and a third position where the sleeve wall is aligned with the port.

Abstract: A pin connector with a seal assembly using a unique wet connect assembly. The pin connector is formed from a tubular having an upper tubular portion and a lower tubular portion. The lower tubular portion has an upper tubular body and a lower tubular body with a lower tubular body face. A first pin engages the wet connect assembly. The first pin has a first pin outer surface, which can be connected to the wet connect assembly.

Abstract: A rolling cone drill bit including multiple cones with regions of intermeshing and non-intermeshing cutter elements. In the non-intermeshed regions, an array of cutter elements is disposed about the cone surface in a non-circumferential arrangement with the cutter elements being mounted at differing radial distances from the bit axis. This non-circumferential arrangement, which may be a spiral, multiple spirals, other patterns of offset cutter elements, or a random arrangement, provides a composite cutting profile having substantial width and bottomhole coverage and is free of ridge-producing voids. In certain embodiments, the composite cutting profiles of the arrays at least partially overlap, and may be arranged to cover a portion of or the entire non-intermeshed region on the cones.

Abstract: A method and apparatus are provided for installing control lines and pipe into a well. The pipe-holding spider that is normally mounted on the rig floor is supported by a table elevated above the rig floor. Supporting the spider on an elevated table provides personnel with access to a portion of the length of the pipe string below the elevated spider and above the rig floor for applying a fastener to secure the control line to the pipe string. The control line is supplied from above the spider and is positioned by a control line guide supported on the spider or a sleeve to pass through the spider outside the path of the pipe gripping members, such as slips.

Abstract: A closed-loop circulating system for drilling wells has control of the flow rates in and out of the wellbore. Kicks and fluid losses are quickly controlled by adjusting the backpressure. Kick tolerance and tripping margins are eliminated by real-time determination of pore and fracture pressure. The system can incorporate a rotating BOP and can be used with underbalanced drilling.

Abstract: A rolling cone drill bit is provided that has gage inserts on the first row from the bit axis to cut to full gage diameter that have a cutting portion enhanced with a layer of super abrasive material. The gage cutting surface has a center axis that is canted to be more normal to the gage curve such that its point of contact at gage is away from the thinner portion of the layer of super abrasive material.

Abstract: A settable and unsettable seal arrangement includes a metal-to-metal seal element; a setting/releasing sleeve in operable communication with the seal element; a retraction ring fixedly attached to the setting/releasing sleeve; a load preservation and unsetting sleeve fixedly attached to the seal element; and a resilient member operably disposed between the setting/releasing sleeve and the load preservation and unsetting sleeve and method for setting and unsetting.

Abstract: A down hole heating system for use with oil and gas wells which exhibit less than optimally achievable flow rates because of high oil viscosity and/or blockage by paraffin (or similar meltable petroleum byproducts). The heating unit the present invention includes shielding to prevent physical damage and shortages to electrical connections within the heating unit while down hole (a previously unrecognized source of system failures in prior art systems). The over-all heating system also includes heat retaining components to focus and contain heat in the production zone to promote flow to, and not just within, the production tubing.

Abstract: A roller cone drill bit may include optimally designed bearing structures and cutting structures. The roller cone drill bit may include three cone assemblies rotatably mounted on respective spindles via respective bearing structures. Each cone assembly may have a respective cutting structure with a minimal moment center located along each respective axis of rotation. Each respective bearing structure has a center point located proximate each respective minimal moment center.

Abstract: A conversion apparatus comprising a first plate and a second plate. The first plate comprises at least one coupling mechanism, and the second plate comprises at least one coupling mechanism. The first plate is configured to couple with a blow-out preventer (BOP) body. The second plate is configured to couple with the first plate a bonnet assembly. A lock ring groove is formed in one of the first plate, the second plate, and between the first plate and the second plate.

Abstract: An earth auger presents a shank having a spiral earth removing structure therearound. The structure first presents a series of spirally positioned housings with cutting teeth therein followed by a spiral cutting edge about the shank. The teeth are radially, vertically and angularly oriented so as to remove earth in a stair-step fashion with a pneumatic drill-like action. The cutting teeth are further arranged so that each subsequent cutting tooth, as measured from the initial shank penetrating end, removes earth prior to the contact of the preceding cutting tooth housing so as to preclude earth contact. The earth relief, the spiral cutting teeth arrangement, the radial displacement of the teeth relative to the shank, the vertical displacement among the teeth and the angular relationship of the teeth, alone and in combination, enhance drilling.

Abstract: A submersible pumping system includes a pump, a motor that drives the pump and a separator assembly. The separator assembly is for separating gas from the fluid and includes an intake and a vent above the intake. Fluid enters the separator assembly at the intake and the vent returns a portion of the fluid into wellbore for recirculation into the intake.

Abstract: A guide frame (1) for an earth drilling apparatus includes a support plate (6) for holding the drive unit (7) and a handle frame (2) having handle sections (17, 18) for holding and guiding the earth drilling apparatus. Operator-controlled elements (19a, 19b, 19c) for controlling the drive unit (7) are arranged in the region of the handle section (18). The handle sections (17, 18) of the handle frame (2) lie in a plane (5) above the support plate (6). The handle frame (2) encloses the drive unit (7) as a closed frame and is connected via a carrier frame (8) to the support plate (6). The carrier plate (8) is fixed to the handle frame (2) via several coupling elements (20). Each coupling element (20) includes a vibration damper (24) which is arranged between the carrier frame (8) and the handle frame (2). In this way, the handle frame is decoupled by the carrier frame from the drive unit with respect to vibration without affecting the bracing of reaction forces via the handle frame.

Abstract: An active differential pressure device (APD device) in fluid communication with a returning fluid creates a differential pressure across the device, which controls pressure below the APD Device. In embodiments, a control unit controls the APD Device to provide a selected pressure differential at a wellbore bottom, adjacent a casing shoe, in an intermediate wellbore location, or in a casing. In one arrangement, the control system is pre-set at the surface such that the APD Device provides a substantially constant pressure differential. In other arrangements, the control system adjusts an operating parameter of the APD Device to provide a desired pressure differential in response to one or more measured parameters. Devices such as an adjustable bypass can be used to control the APD Device. In other embodiments, one or more flow control devices coupled to the return fluid reduce the effective pressure differential provided by the APD Device.