Abstract: Methods and apparatus enable reliable and improved isolation between two portions of a bore extending through a casing string disposed in a borehole. A downhole deployment valve (DDV) may provide the isolation utilizing a valve member such as a flapper that is disposed in a housing of the DDV and is designed to close against a seat within the housing. The DDV includes an operating mechanism for opening/closing the DDV. In use, pressure in one portion of a well that is in fluid communication with a well surface may be bled off and open at well surface while maintaining pressure in another portion of the casing string beyond the DDV.

Abstract: A method of drilling a subsea wellbore includes drilling the wellbore by injecting drilling fluid through a tubular string extending into the wellbore from an offshore drilling unit (ODU) and rotating a drill bit disposed on a bottom of the tubular string. The method further includes, while drilling the wellbore: mixing lifting fluid with drilling returns at a flow rate proportionate to a flow rate of the drilling fluid, thereby forming a return mixture. The lifting fluid has a density substantially less than a density of the drilling fluid. The return mixture has a density substantially less than the drilling fluid density. The method further includes, while drilling the wellbore: measuring a flow rate of the returns or the return mixture; and comparing the measured flow rate to the drilling fluid flow rate to ensure control of a formation being drilled.

Abstract: A flow sub for use with a drill string includes: a tubular housing having a longitudinal bore formed therethrough and a flow port formed through a wall thereof; a bore valve operable between an open position and a closed position, wherein the bore valve allows free passage through the bore in the open position and isolates an upper portion of the bore from a lower portion of the bore in the closed position; and a sleeve disposed in the housing and movable between an open position where the flow port is exposed to the bore and a closed position where a wall of the sleeve is disposed between the flow port and the bore; and a bore valve actuator operably coupling the sleeve and the bore valve such that opening the sleeve closes the bore valve and closing the sleeve opens the bore valve.

Abstract: Methods and apparatus enable reliable and improved isolation between two portions of a bore extending through a casing string disposed in a borehole. A downhole deployment valve (DDV) may provide the isolation utilizing a valve member such as a flapper that is disposed in a housing of the DDV and is designed to close against a seat within the housing. The DDV includes an operating mechanism for opening/closing the DDV. In use, pressure in one portion of a well that is in fluid communication with a well surface may be bled off and open at well surface while maintaining pressure in another portion of the casing string beyond the DDV.

Abstract: Methods and apparatus enable reliable and improved isolation between two portions of a bore extending through a casing string disposed in a borehole. A downhole deployment valve (DDV) may provide the isolation utilizing a valve member such as a flapper that is disposed in a housing of the DDV and is designed to close against a seat within the housing. The DDV includes an operating mechanism for opening/closing the DDV. In use, pressure in one portion of a well that is in fluid communication with a well surface may be bled off and open at well surface while maintaining pressure in another portion of the casing string beyond the DDV.

Abstract: Methods and apparatus enable reliable and improved isolation between two portions of a bore extending through a casing string disposed in a borehole. A downhole deployment valve (DDV) may provide the isolation utilizing a valve member such as a flapper that is disposed in a housing of the DDV and is designed to close against a seat within the housing. The DDV includes an operating mechanism for opening/closing the DDV. In use, pressure in one portion of a well that is in fluid communication with a well surface may be bled off and open at well surface while maintaining pressure in another portion of the casing string beyond the DDV.

Abstract: Methods and apparatus enable reliable and improved isolation between two portions of a bore extending through a casing string disposed in a borehole. A downhole deployment valve (DDV) may provide the isolation utilizing a valve member such as a flapper that is disposed in a housing of the DDV and is designed to close against a seat within the housing. The DDV includes an operating mechanism for opening/closing the DDV. In use, pressure in one portion of a well that is in fluid communication with a well surface may be bled off and open at well surface while maintaining pressure in another portion of the casing string beyond the DDV.

Abstract: A method for drilling a wellbore includes drilling the wellbore by advancing the tubular string longitudinally into the wellbore; stopping drilling by holding the tubular string longitudinally stationary; adding a tubular joint or stand of joints to the tubular string while injecting drilling fluid into a side port of the tubular string, rotating the tubular string, and holding the tubular string longitudinally stationary; and resuming drilling of the wellbore after adding the joint or stand.

Abstract: Methods and apparatus for communicating between surface equipment and downhole equipment. One embodiment of the invention provides a wellhead assembly that allows electrical power and signals to pass into and out of the well during drilling operations, without removing the valve structure above the wellhead. Another embodiment of the invention provides an electromagnetic casing antenna system for two-way communication with downhole tools. Another embodiment of the invention provides an antenna module for a resistivity sub that effectively controls and seals the primary/secondary interface gap.

Abstract: Methods and apparatus for utilizing a downhole deployment valve (DDV) to isolate a pressure in a portion of a bore are disclosed. The DDV system can include fail safe features such as selectively extendable attenuation members for decreasing a falling object's impact, a normally open back-up valve member for actuation upon failure of a primary valve member, or a locking member to lock a valve member closed and enable disposal of a shock attenuating material on the valve member. Actuation of the DDV system can be electrically operated and can be self contained to operate automatically downhole without requiring control lines to the surface. Additionally, the actuation of the DDV can be based on a pressure supplied to an annulus.

Abstract: Methods and apparatus for utilizing a downhole deployment valve (DDV) to isolate a pressure in a portion of a bore are disclosed. The DDV system can include fail safe features such as selectively extendable attenuation members for decreasing a falling object's impact, a normally open back-up valve member for actuation upon failure of a primary valve member, or a locking member to lock a valve member closed and enable disposal of a shock attenuating material on the valve member. Actuation of the DDV system can be electrically operated and can be self contained to operate automatically downhole without requiring control lines to the surface. Additionally, the actuation of the DDV can be based on a pressure supplied to an annulus.

Abstract: Methods and apparatus for communicating between surface equipment and downhole equipment. One embodiment of the invention provides a wellhead assembly that allows electrical power and signals to pass into and out of the well during drilling operations, without removing the valve structure above the wellhead. Another embodiment of the invention provides an electromagnetic casing antenna system for two-way communication with downhole tools. Another embodiment of the invention provides an antenna module for a resistivity sub that effectively controls and seals the primary/secondary interface gap.

Abstract: Methods and apparatus for utilizing a downhole deployment valve (DDV) to isolate a pressure in a portion of a bore are disclosed. The DDV system can include fail safe features such as selectively extendable attenuation members for decreasing a falling object's impact, a normally open back-up valve member for actuation upon failure of a primary valve member, or a locking member to lock a valve member closed and enable disposal of a shock attenuating material on the valve member. Actuation of the DDV system can be electrically operated and can be self contained to operate automatically downhole without requiring control lines to the surface. Additionally, the actuation of the DDV can be based on a pressure supplied to an annulus.

Abstract: Methods and apparatus enable reliable and improved isolation between two portions of a bore extending through a casing string disposed in a borehole. A downhole deployment valve (DDV) may provide the isolation utilizing a valve member such as a flapper that is disposed in a housing of the DDV and is designed to close against a seat within the housing. The DDV includes an operating mechanism for opening/closing the DDV. In use, pressure in one portion of a well that is in fluid communication with a well surface may be bled off and open at well surface while maintaining pressure in another portion of the casing string beyond the DDV.

Abstract: Methods and apparatus for communicating between surface equipment and downhole equipment. One embodiment of the invention provides a wellhead assembly that allows electrical power and signals to pass into and out of the well during drilling operations, without removing the valve structure above the wellhead. Another embodiment of the invention provides an electromagnetic casing antenna system for two-way communication with downhole tools. Another embodiment of the invention provides an antenna module for a resistivity sub that effectively controls and seals the primary/secondary interface gap.

Abstract: Methods and apparatus for communicating between surface equipment and downhole equipment. One embodiment of the invention provides a wellhead assembly that allows electrical power and signals to pass into and out of the well during drilling operations, without removing the valve structure above the wellhead. Another embodiment of the invention provides an electromagnetic casing antenna system for two-way communication with downhole tools. Another embodiment of the invention provides an antenna module for a resistivity sub that effectively controls and seals the primary/secondary interface gap.

Abstract: Methods and apparatus for utilizing a downhole deployment valve (DDV) to isolate a pressure in a portion of a bore are disclosed. Any combination of fail safe features may be used with or incorporated into the DDV such as redundant valve members, an upward opening flapper valve or a metering flapper below a sealing valve. In one aspect, a barrier or diverter located in the bore above a valve member of the DDV permits passage through the bore when the valve member is open and actuates when the valve member is closed. Once actuated, the barrier or diverter either stops or diverts any dropped objects prior to the dropped object reaching and potentially damaging the valve member. In another aspect, the tool string tripped in above the DDV includes an acceleration actuated brake that anchors the tool string to a surrounding tubular if the tool string is dropped.

Abstract: Methods and apparatus for utilizing a downhole deployment valve (DDV) to isolate a pressure in a portion of a bore are disclosed. The DDV system can include fail safe features such as selectively extendable attenuation members for decreasing a falling object's impact, a normally open back-up valve member for actuation upon failure of a primary valve member, or a locking member to lock a valve member closed and enable disposal of a shock attenuating material on the valve member. Actuation of the DDV system can be electrically operated and can be self contained to operate automatically downhole without requiring control lines to the surface. Additionally, the actuation of the DDV can be based on a pressure supplied to an annulus.

Abstract: Methods and apparatus for communicating between surface equipment and downhole equipment. One embodiment of the invention provides a wellhead assembly that allows electrical power and signals to pass into and out of the well during drilling operations, without removing the valve structure above the wellhead. Another embodiment of the invention provides an electromagnetic casing antenna system for two-way communication with downhole tools. Another embodiment of the invention provides an antenna module for a resistivity sub that effectively controls and seals the primary/secondary interface gap.

Abstract: Methods and apparatus for utilizing a downhole deployment valve (DDV) to isolate a pressure in a portion of a bore are disclosed. Any combination of fail safe features may be used with or incorporated into the DDV such as redundant valve members, an upward opening flapper valve or a metering flapper below a sealing valve. In one aspect, a barrier or diverter located in the bore above a valve member of the DDV permits passage through the bore when the valve member is open and actuates when the valve member is closed. Once actuated, the barrier or diverter either stops or diverts any dropped objects prior to the dropped object reaching and potentially damaging the valve member. In another aspect, the tool string tripped in above the DDV includes an acceleration actuated brake that anchors the tool string to a surrounding tubular if the tool string is dropped.