Abstract: An anchor (A) or guide assembly (GA) connects with a workstring (WS) that may include a drill string (DS). The guide assembly (GA) includes an internal tubular member (ITM) to releasably connect with the workstring (WS). A tube (CT) is within the internal tubular member (ITM). The internal tubular member (ITM) is releasably secured with an outer tubular member (OTM). The internal tubular member (ITM) is releasably secured with an anchor surface. The workstring (WS) is released from the internal tubular member (ITM) to move relative to the guide assembly (GA) to extend the tube (CT) from the internal tubular member (ITM) for performing various operations.

Abstract: A retrievable whipstock which can be hydraulically set within a wellbore and following the drilling procedure mechanically released and retrieved for future use. The whipstock includes a whip which directs a milling tool from the main well and a hydraulically actuated packer or anchor for setting the whipstock in the wellbore. The whip includes ratchet teeth on its side edges for mating engagement with a retrieval tool. The retrieval tool includes a nose piece to ensure proper orientation relative to the whipstock and a clamping ring with ratchet teeth to engage the teeth of the whip. The whipstock is released through the application of tension through the retrieval tool allowing removal from the wellbore.

Abstract: Offshore well slots are recovered by cutting off old drive or surface pipe below the mud line to form a stub end. A new drivepipe is installed with a guide and shield device disposed on the scarfed lower end or "mule shoe" of the new drivepipe. The guide and shield device includes a saddle contiguous with the lower end of the new drivepipe having one or more hooks formed on the outer surface thereof for engagement with the stub end to locate the device and the new drivepipe. Shear pins interconnect the new drivepipe with the device and are sheared in response to downward driving action on the new drivepipe or allowing the full weight of the drivepipe to be exerted on the shield device after engagement with the old drivepipe.

Abstract: A whipstock setting apparatus includes a whipstock with a mandrel secured thereto and depending therefrom. A cutter, or mill is connected to a work string and releasably connected to the whipstock. A packer assembly including a mechanical weight set packer and upper and lower cone and slip means are mounted on the mandrel above and below the packer. The mandrel is releasably connected to the packer assembly to prevent premature longitudinal movement therebetween and to accommodate relative longitudinal movement therebetween when desired.

Abstract: Core samples are obtained through production wells by inserting a milling tool through the production tubing string on the distal end of coilable tubing to mill out a window in the well casing. The milling tool is deflected by a whipstock set in the casing at a predetermined point and encased in cement which, upon setting, is bored to form a pilot bore for the milling tool. A fluid-motor-driven core barrel is run into the well on the coilable tubing after the milling operation is complete and core drilling is carried out in an underbalanced condition by reducing wellbore pressure through gas lift so as to minimize core invasion by wellbore fluids, including spent core drilling fluids.

Abstract: A one-trip whipstock assembly incorporating a hydraulically set anchor which includes an interlock for maintaining the anchor in its set position upon interruption of hydraulic pressure. The anchor is connected to the lower end of the assembly which also includes a whipstock for diverting cutting tools and a locator sub for positioning the assembly in the cased well bore. The whipstock assembly is designed to be run into the well using a running string or a mill attached to the upper end of the whipstock in order to locate and set the whipstock and mill the casing in only one trip.

Abstract: There is provided a new and useful coring assembly for mounting on the end of a drill string and comprising a core barrel; abrading means on at least a part of the core barrel; a reaming collar mounted about a lower section of the core barrel and selectable between a first condition in which the collar is rotatable with the barrel and a second condition in which the collar is rotatable relative to and slidable longitudinally relative to the core barrel; a housing suspended from the core barrel; a deflection crank extending between the housing and the core barrel; and means within the housing for transferring power from a power source to the crank for selectively rotating the crank for moving the core barrel between a first position in which the core barrel and the housing are aligned and a second position in which the barrel and the housing are not aligned.

Abstract: Apparatus and method for deflecting the drilling direction of a rotary drill string and drill bit through a borehole wall include an anchor, a housing, and a chute. The anchor anchors the apparatus in the borehole. The housing is connectable to the anchor and has an uphole end, a downhole end, a sidewall extending between the uphole end and the downhole end, and a passageway extending through the housing. The passageway has an entrance through the uphole end of the housing and an exit through the sidewall of the housing. The chute is slidably disposed in the housing passageway and has an uphole end, a downhole end, a sidewall extending between the uphole end and the downhole end, and a passageway extending through the chute from the uphole end through the downhole end. The chute passageway passes the drill bit and drill string through the chute.

Abstract: Apparatus for radial drilling into selected formations adjacent an earth borehole, the apparatus consisting of concentric, counterwound spring shafts operating in conjunction with a rotary drive source and a guide housing positionable to direct the rotating bendable shaft down and outward in a radial direction. The apparatus includes bit weight limiting means and guide housing locking means which enable effective radial drilling operation in any selected angular and/or radial directions to greatly multiply and enlarge the producing formation interface.

Abstract: An electrode well extending into a subterranean formation containing viscous hydrocarbons comprising a plurality of electrode tubes which are formed by extension of an elongated tube from the surface above the formation using a coiled tube injection unit or lowering the tubes on drill pipe, diverting the tubes radially outwardly from the wellbore into the formation and penetrating the formation with the electrode tubes using hydraulic jetting action by pumping fluid through the tubes during the insertion process. The tubes are installed axially spaced apart using respective tube guide members which are inserted into the wellbore and operate to form a curved path for diverting the tubes into the formation during the insertion process and for supporting the end of the tube after its insertion into the wellbore.

Abstract: A method and apparatus for forming substantially horizontal drain holes into a subterranean formation from a substantially vertical cased wellbore. A casing anchor is set in the casing adjacent the formation and a whipstock is used to mill a window in the casing. A flexible drill string is then used to drill the horizontal drain hole through the window. In one modification, a deflection tool having a deflection surface which has a radius of curvature of between 11 and 28 feet is used for both the milling and drilling operations. In another modification, the milling operation is carried out with a sidetracking whipstock which is then replaced with the above-described deflection tool to carry out the drilling operation. In still another modification, a whipstock adaptor is positioned onto a sidetracking whipstock after the milling operation to convert the sidetracking whipstock into a deflecting tool having the desired radius of curvature for carrying out the drilling operation.

Abstract: A compass card is provided for use in achieving the angular alignment of a whipstock relative to a whipstock anchor having a keyway therein for subsequent insertion in a packer apparatus for use in a subterranean well. The compass card comprises an annular card having polar coordinates in mirror image reverse relationship on one face thereof and may have a plurality of sheet-like magnetic elements secured to the other face adjacent a central opening therein.

Abstract: The device disclosed includes a housing which can be moved through the bore hole and anchored in the desired location for drilling a lateral hole. Located in the housing is a drill string guide or conductor having a bendable lower end. The conductor is movable to a position where its lower end is either inherently or forceably bent so that it provides a curved path leading toward the side wall of the bore hole. The conductor guides a drill string extending through the conductor to cause the drill string to drill a lateral hole in the side wall of the well bore. The drill string and conductor can be retracted into the housing when the lateral hole has been drilled, or a portion of the drill string may be left in the lateral hole as a drain pipe.