Abstract: A process for retrieving a bottom hole assembly through a casing string may include: installing a casing string in a borehole, the casing string including a bottom hole assembly releasably engaged thereto and moveable through an inner diameter of the casing string; releasing the bottom hole assembly from engagement with the casing string; reducing hydrostatic pressure in the casing string inner diameter above the bottom hole assembly so that the casing string inner diameter pressure above the bottom hole assembly is lower than a fluid pressure below the bottom hole assembly; permitting reverse circulation down through an annulus between the casing string and the borehole to permit the bottom hole assembly to rise up through the casing string toward the surface; and retrieving the bottom hole assembly from the casing string.

Abstract: A wireline entry sub includes a body having an upper end, a lower end and a longitudinal, center axis therebetween, the body adapted for connection below a top drive to a wellbore string of tubulars; a slot on the body open a depth from a body outer surface to at least the longitudinal center axis; a wireline entry port extending through the body from the slot to open adjacent the lower end; and means for facilitating rig up of the wireline entry sub.

Abstract: A method for drilling boreholes using casing as the drill string and for removing a drilling assembly from the wellbore while leaving the casing in the well bore. In the method, the drilling assembly is prepared for removal from the wellbore by launching a release tool and manipulating the drilling assembly using the release tool.

Abstract: A pipe handling device for mounting to use with a top drive and possibly a pipe engaging apparatus, includes a link arm having a first end pivotally connectable to move with the top drive and an outboard end pivotally connectable to a pipe elevator segment, and a drive system to drive the outboard end of the link arm at least between a lower position and a raised position. A pipe handling system and method may include or employ the pipe handling device.

Abstract: A valve (30), a drill string valve assembly (10) and a method of drilling using compressed fluid as a drill drilling fluid are described. The valve and valve assembly (10) may be used in order to prevent escape of compressed fluid during the time that a connection is being made into the drill string. The valve (10) can be insertable into a drill string inner diameter to seal against fluid passage past the body except through the valve (30) and can be selected to maintain fluid pressure in the drill string when the upper end of the drill string is open to atmosphere. The valve can also be capable of being releasably engaged to a drive mechanism, such as a top drive (40) which is handling the drill string (12) to be slidably moved within the drill string, as driven by the drive mechanism, but releasable from the drive mechanism, when the drive mechanism is removed from the drill string.

Abstract: A crimpable wear band (105) tool has been invented for installation on casing (6), used in well bore drilling. A wear band (105) is provided having a cylindrical body which when coaxially placed over a pipe and substantially radially inwardly displaced at a plurality of points (i.e. crimped) about the circumference of a section of cylindrical body, attaches to the pipe to create a connection having structurally significant axial and torque load transfer capacity. When crimped according to the methods of the present invention, the load transfer capacity of the connection between the wear band (105) tool and the pipe (6) can be arranged to substantially prevent significant relative movement of the wear band tool on the pipe under loads that may be encountered when using one or more of the pipes as components of a tubular string used for drilling or running the casing in to complete a well bore.

Abstract: A method for drilling a borehole includes; providing a drill string of drill pipe including a center bore, a distal end, a bit assembly at the distal end; hanging a liner from the drill string, thereby forming an annular space between the drill string and the liner and with the bit assembly extending from a lower end of the liner; positioning the drill string with the liner attached thereto in a borehole such that a second annular space is formed between the liner and the borehole wall; operating the bit assembly to proceed with drilling the borehole; and circulating drilling fluid down through the center bore of the drill string out through the bit assembly and down through the second annular space between the liner and the borehole wall, the drilling fluid returning up through the annular space between the drill string and the liner.

Abstract: A cement float for use in a wellbore tubing string includes: a mandrel having a bore extending from a first end to a second end including a fluid flow control device therein, and outer surfaces defining a tapering outer diameter from the first end to the second end; an outer lock sleeve having an outer surface and a sleeve bore therethrough, the outer lock sleeve retained at least about the outer surfaces of the mandrel surfaces and defining interfaces therebetween, the sleeve being expandable radially outwardly by driving the mandrel against the sleeve bore to place the cement float in anchoring position within the tubing string.

Abstract: A crimpable centralizer has been invented for installation on pipe, such as would be useful in well bore drilling and casing operations. The present invention provides a centralizer having a cylindrical body which when coaxially placed over a pipe and substantially radially inwardly displaced at a plurality of points (i.e. crimped) about the circumference of a section of the cylindrical body, attaches to the pipe to create a connection having structurally significant axial and torque load transfer capacity. When crimped according to the methods of the present invention, the load transfer capacity of the connection between the centralizer and the pipe can be arranged to substantially prevent significant relative movement of the centralizer on the pipe under loads that may be encountered when using one or more of the pipes as components of a tubular string used for drilling or completing well bores.

Abstract: A method for drilling boreholes using casing (16) as the drill string and for advancing a casing string toward the bottom of the borehole is described. In the method, the drilling assembly (26) is used as a guide over which the drill string (16) is advanced toward the bottom of the borehole prior to removing the drilling assembly from the wellbore.

Abstract: An axial force generating tool for applying a force on a structure positioned within a borehole is taught. The tool includes a housing (19) sized to fit within the borehole in which the tool is required to act; an outer seal (38) disposed about the housing and selected to create a seal between the housing and the borehole; an inner bore (32) through the housing including a seal to prevent flow from the inner bore out through the lower end; an opening (34) to the inner bore above the seal; a bracing means (36) for maintaining the housing against axial movement in the borehole once the housing is in a selected position within the borehole; a piston (27) mounted in sliding engagement wiht the housing for axial movement relative to the housing, the piston positioned to act between a pressure differential establishable between the inner bore and the borehole between the seal and the lower end to drive the piston axially relative to the housing; and a grapple connected to the piston for axial movement therewith.

Abstract: A method for drilling in unconsolidated formation is taught. In particular, a method for borehole stabilization in an unconsolidated formation includes providing a drill string; rotating the drill string to drive a drill bit to drill a borehole having a borehole wall; driving the drill string against the borehole wall while rotating the drill string to plaster the surface of the borehole wall.

Abstract: A drill string valve assembly includes a tubular valve body, including an outer surface and an inner bore for housing a valve mechanism to control fluid flow through the bore; and an axial load support releasably securable to the outer surface of the valve body, the axial load support including an upper releasable load bearing connection to the tubular body and a lower releasable load bearing connection to the tubular valve body.

Abstract: A shoulder ring (10) for installing in the J-space between the installed pin ends within a coupling collar is taught having a body with a central opening therethrough, a first end face (12) on the body, an opposite end face (14) on the body, an inner surface (16) adjacent the central opening and extending between the first end face and the opposite end face and an outer surface (18) extending between the first end face and the opposite end face, the body having a substantially uniform cross sectional shape between the first end face, the opposite end face, the inner surface and the outer surface and the ring shaped such that its radius to the outer surface varies around the outer surface circumference to form a plurality of lobes (12).

Abstract: A method for drilling a borehole includes; providing a drill string of drill pipe including a center bore, a distal end, a bit assembly at the distal end; hanging a liner from the drill string, thereby forming an annular space between the drill string and the liner and with the bit assembly extending from a lower end of the liner; positioning the drill string with the liner attached thereto in a borehole such that a second annular space is formed between the liner and the borehole wall; operating the bit assembly to proceed with drilling the borehole; and circulating drilling fluid down through the center bore of the drill string out through the bit assembly and down through the second annular space between the liner and the borehole wall, the drilling fluid returning up through the annular space between the drill string and the liner. An apparatus for use in this method is also described.

Abstract: An apparatus for facilitating the connection of tubulars using a top drive, which apparatus comprises a body (2; 102) connectable to said top drive, said body (2; 102) comprising at least one gripping element (5; 105) radially displaceable by hydraulic or pneumatic fluid to drivingly engage said tubular (30; 110) to permit a screw connection between said tubular and a further tubular to be tightened to the required torque.

Abstract: A method and apparatus for drilling directional wellbores using a casing string as a drill stem is taught. A retrievable bit is mounted at an end of the casing string and either a mud motor with a bent housing and/or bent sub or a rotary steerable tool is used to direct the bit to drill directionally.

Abstract: A method for drilling in unconsolidated formation is taught. In particular, a method for borehole stabilization in an unconsolidated formation includes providing a drill string; rotating the drill string to drive a drill bit to drill a borehole having a borehole wall; driving the drill string against the borehole wall while rotating the drill string to plaster the surface of the borehole wall.

Abstract: A method for preparing casing for use in a wellbore such as for example, in preparation, for use to line a borehole through a formation or to act as a drill string and thereafter to remain in hole. In the method, a device supporting the use of the wellbore casing is crimped onto the outer surface of the casing. The device supporting casing use can be to facilitate run in through the borehole, to maintain positioning relative to the borehole, to accommodate wear against the wall of the borehole into which the casing is run or to enhance the results of cementing. The devices supporting the use of the casing are attached by crimping to the casing to create a connection having structurally significant axial and torque load transfer capacity.

Abstract: A tubing centralizer for borehole drilling disclosed. The centralizer includes a retaining collar and an outer sleeve. In a method for installing the centralizer onto a joint of tubing, the retaining collar is mounted onto the joint of tubing and the outer sleeve is installed thereover.