Abstract: The present invention relates to a wiper plug and internal drop ball mechanism that may be used in conjunction with a downhole surge reduction tool to run, hang, and cement casing liners in a wellbore. The apparatus of the present invention comprises a wiper plug assembly removably attached to the drill string within the casing liner, a drop ball sub attached below the wiper plug assembly which releases a float valve actuator ball having a diameter larger than the drill string, and float equipment having a plurality of flapper valves. The apparatus of the present invention may further comprise a diverter tool connected between the drill string and the casing liner.

Abstract: A method and apparatus for use in the oil well industry for running in drilling/production liners and sub-sea casings down a borehole on a drill pipe using a running tool with the benefits of surge pressure reduction are disclosed. A surge pressure reduction tool in accordance with the present invention includes a diverter device having a set of flow holes which diverter device can be shifted between a “surge pressure reduction” mode and a “cementing” or “circulation” mode. A tool in accordance with the present invention further includes a volume compensation device which enables the diverter device to shift axially downward into the cementing or circulation mode even where the drilling/production liner or sub-sea casing is plugged with drill cuttings or downhole debris.

Abstract: The present invention relates to a float collar apparatus for regulating the passage of fluid through a drilling/production liner or sub-sea casing. Apparatus of the present invention is fabricated using plastic flapper valves and valve-actuating sleeve components in contrast to prior art float collar components which are fabricated almost entirely of hard metals. Particularly, the plastic may be nylon, phenolic, or a phenolic-nylon laminate. The use of plastic components in the float collar apparatus of the present invention provides a substantial reduction in time and resources expended during drilling out of the float collar once cementing operations are completed. Additionally, the float collar apparatus of the present invention is fabricated from a pre-determined combination of plastic components and metal components thereby ensuring that the improved float collar can still endure substantial hydrostatic stresses encountered during casing liner running in and cementing operations.

Abstract: The present invention relates to a float collar apparatus for regulating the passage of fluid through a casing liner or sub-sea casing. Apparatus of the present invention is fabricated using plastic flapper valves and sleeve components in contrast to prior art float collar components which are fabricated almost entirely of hard metals. The use of plastic components in the float collar apparatus of the present invention provides a substantial reduction in time and resources expended during drilling out of the float collar once cementing operations are completed. Additionally, the float collar apparatus of the present invention is fabricated from a pre-determined combination of plastic components and metal components thereby ensuring that the improved float collar can still endure substantial hydrostatic stresses encountered during casing liner running in and cementing operations.

Abstract: Improvements are disclosed in surge reduction tools for running in casings or casing liners downhole with the ability to restore circulation in the event a tight hole condition is encountered. The improved tool includes among other features 1.) an axial indexing apparatus which allows the valving sleeve to be moved downward in predetermined increments to allow alternate closing and opening of the vent ports, 2.) a camming sleeve and Bellville spring washers which provide the surge reduction tool with a more predictable release pressure than has heretofore been available, 3.) a dart directing sleeve which has a smaller, smoother bore than the drill string and provides the important function of aligning the dart before it lands in the seat so that the dart resistance when passing through the seat is minimized, and 4.

Abstract: A method and apparatus for use in the oil well industry for running in drilling/production liners and sub-sea casings down a borehole through drilling fluid on a drill pipe using a multifunction diverter tool with the benefits of surge pressure reduction are disclosed. In accordance with the present invention, a multi-function diverter tool includes a housing assembly with a set of flow holes formed therein and a sliding sleeve arranged within the housing assembly having two sets of flow ports formed therein at different axial locations along the sleeve. By aligning either set of flow ports of the sleeve with the flow holes of the housing, the tool is set in a “surge pressure reduction” mode. By shifting, or axially indexing, the sleeve downward, the set of flow holes becomes blocked by the sleeve thus setting the tool in a “circulation” or “cementing” mode. This shifting or indexing is accomplished using an indexing mechanism.

Abstract: The present invention relates to a wiper plug and internal drop ball mechanism that may be used in conjunction with a downhole surge reduction tool to run, hang, and cement casing liners in a wellbore. The apparatus of the present invention comprises a wiper plug assembly removably attached to the drill string within the casing liner, a drop ball sub attached below the wiper plug assembly which releases a float valve actuator ball having a diameter larger than the drill string, and float equipment having a plurality of flapper valves. The apparatus of the present invention may further comprise a diverter tool connected between the drill string and the casing liner.

Abstract: The present invention relates to a wiper plug and internal drop ball mechanism that may be used in conjunction with a downhole surge reduction tool to run, hang, and cement casing liners in a wellbore. The apparatus of the present invention comprises a wiper plug assembly removably attached to the drill string within the casing liner, a drop ball sub attached below the wiper plug assembly which releases a float valve actuator ball having a diameter larger than the drill string, and float equipment having a plurality of flapper valves. The apparatus of the present invention may further comprise a diverter tool connected between the drill string and the casing liner.

Abstract: Method and apparatus are disclosed for use in cementing a tubular member which is run into a borehole using a drill string. A landing collar is attached to the tubular member near the bottom of the tubular member, and the landing collar has an opening at least five inches in diameter. A liner wiper assembly is releasably suspended from the drill string. The liner wiper assembly comprises a lower liner wiper plug comprising float valves and an upper liner wiper plug. With the method and apparatus of the present invention, plugging problems are minimized.

Abstract: The present invention relates to improvements in drill slip assemblies for use in holding a drill pipe or other tubular member in a vertical position above or within a wellbore. The invention comprises a plurality of slip segments assembled in a slip bowl, each segment containing a plurality of dies which grip the tubular member to prevent any axial displacement. The invention provides at least three improvements over prior art drill slips. First, the outer surface of the slip segment assembly, particularly the lower nose region, is fully supported by the inner surface of the slip bowl such that no portion of the slip segment assembly extends below the bowl. Second, the slip segments are fabricated from forged steel, making them more durable and able to carry higher loads. Third, each die in the lowermost set of hardened dies is fabricated having a rounded bottom end with a tapered profile to complement the rounded bottom of the axial grooves cut into each slip segment.

Abstract: The present invention provides a drop ball sub that may be used to drop a large ball having an outer diameter larger than the inner diameter of a restriction in the wellbore such as the running tool used to run a first casing string through a second casing string. A smaller ball is used to control dropping of the large ball. The smaller ball has an outer diameter smaller than the restriction. The drop ball sub of the present invention may be used to operate any downhole tool that would benefit by receipt of a large ball. By dropping a larger ball, in one use of the invention larger valves can be controlled in the float equipment that provide a larger fluid flow path. A larger fluid flow path reduces surge pressure and enables the system to handle more debris. The present invention provides a system that preferably provides for a diverter tool above the running tool and a diverter tool below the running tool.

Abstract: The present invention relates to a wiper plug and internal drop ball mechanism that may be used in conjunction with a downhole surge reduction tool to run, hang, and cement casing liners in a wellbore. The apparatus of the present invention comprises a wiper plug assembly removably attached to the drill string within the casing liner, a drop ball sub attached below the wiper plug assembly which releases a float valve actuator ball having a diameter larger than the drill string, and float equipment having a plurality of flapper valves. The apparatus of the present invention may further comprise a diverter tool connected between the drill string and the casing liner.

Abstract: The present invention relates to a wiper plug and internal drop ball mechanism that may be used in conjunction with a downhole surge reduction tool to run, hang, and cement casing liners in a wellbore. The apparatus of the present invention comprises a wiper plug assembly removably attached to the drill string within the casing liner, a drop ball sub attached below the wiper plug assembly which releases a float valve actuator ball having a diameter larger than the drill string, and float equipment having a plurality of flapper valves. The apparatus of the present invention may further comprise a diverter tool connected between the drill string and the casing liner.

Abstract: Improvements are disclosed in surge reduction tools for running in casings or casing liners downhole with the ability to restore circulation in the event a tight hole condition is encountered. The improved tool includes among other features 1.) an axial indexing apparatus which allows the valving sleeve to be moved downward in predetermined increments to allow alternate closing and opening of the vent ports, 2.) a camming sleeve and Bellville spring washers which provide the surge reduction tool with a more predictable release pressure than has heretofore been available, 3.) a dart directing sleeve which has a smaller, smoother bore than the drill string and provides the important function of aligning the dart before it lands in the seat so that the dart resistance when passing through the seat is minimized, and 4.

Abstract: An improved float shoe/collar apparatus is provided for use during casing run in or floated in. The apparatus has an inner tubular member and outer tubular member, movable upon release of shear pins to cause longitudinal movement relative to each other. The movement of the inner tubular member closes a plurality of downward jets and opens a plurality of upward jets. The apparatus also is equipped with a set of check valves, held open on run in, and activated to close upon cementing to prevent “u-tubing” of fluid back into the casing.

Abstract: The present invention relates to improvements in drill slip assemblies for use in holding a drill pipe or other tubular member in a vertical position above or within a wellbore. The invention comprises a plurality of slip segments assembled in a slip bowl, each segment containing a plurality of dies which grip the tubular member to prevent any axial displacement. The invention provides at least three improvements over prior art drill slips. First, the outer surface of the slip segment assembly, particularly the lower nose region, is fully supported by the inner surface of the slip bowl such that no portion of the slip segment assembly extends below the bowl. Second, the slip segments are fabricated from forged steel, making them more durable and able to carry higher loads. Third, each die in the lowermost set of hardened dies is fabricated having a rounded bottom end with a tapered profile to complement the rounded bottom of the axial grooves cut into each slip segment.

Abstract: The present invention provides a drop ball sub that may be used to drop a large ball having an outer diameter larger than the inner diameter of a restriction in the wellbore such as the running tool used to run a first casing string through a second casing string. A smaller ball is used to control dropping of the large ball. The smaller ball has an outer diameter smaller than the restriction. The drop ball sub of the present invention may be used to operate any downhole tool that would benefit by receipt of a large ball. By dropping a larger ball, in one use of the invention larger valves can be controlled in the float equipment that provide a larger fluid flow path. A larger fluid flow path reduces surge pressure and enables the system to handle more debris. The present invention provides a system that preferably provides for a diverter tool above the running tool and a diverter tool below the running tool.

Abstract: A float shoe/collar apparatus and method is disclosed for multi-purpose use in running a tubular string such as a casing string or liner into a wellbore and for optimizing cementing operations. In one presently preferred embodiment, the present invention permits auto filling of the tubular string as the string is lowered into the wellbore. If desired, circulation can be effected through down jets for washing the wellbore as necessary. After the tubular string is positioned, the down jets can be blocked off and up jets opened to thereby direct cement upwardly to optimize cement placement. Check valves can also be activated in accord with the present invention to prevent flow from the wellbore into the tubular string. In one embodiment, the invention comprises an inner member and tubular member. The inner member is movable upon release of shear pins to cause longitudinal movement relative to the outer member.

Abstract: The present invention relates to improvements in drill slip assemblies for use in holding a drill pipe or other tubular member in a vertical position above or within a wellbore. The invention comprises a plurality of slip segments assembled in a slip bowl, each segment containing a plurality of dies which grip the tubular member to prevent any axial displacement. The invention provides at least three improvements over prior art drill slips. First, the outer surface of the slip segment assembly, particularly the lower nose region, is fully supported by the inner surface of the slip bowl such that no portion of the slip segment assembly extends below the bowl. Second, the slip segments are fabricated from forged steel, making them more durable and able to carry higher loads. Third, each die in the lowermost set of hardened dies is fabricated having a rounded bottom end with a tapered profile to complement the rounded bottom of the axial grooves cut into each slip segment.

Abstract: Method and apparatus are disclosed for use in cementing a tubular member which is run into a borehole using a drill string. A landing collar is attached to the tubular member near the bottom of the tubular member, and the landing collar has an opening at least five inches in diameter. A liner wiper assembly is releasably suspended from the drill string. The liner wiper assembly comprises a lower liner wiper plug comprising float valves and an upper liner wiper plug. With the method and apparatus of the present invention, plugging problems are minimized.