초록 ▼

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 m

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.

대표청구항 ▼

The invention claimed is: 1. A method of drilling a wellbore, comprising: running a drill string into the wellbore and a bore of a casing string, the casing string comprising: a first hydraulic port, a valve member moveable between an open position and a closed position, wherein the valve member su

The invention claimed is: 1. A method of drilling a wellbore, comprising: running a drill string into the wellbore and a bore of a casing string, the casing string comprising: a first hydraulic port, a valve member moveable between an open position and a closed position, wherein the valve member substantially seals a first portion of the casing bore from a second portion of the casing bore in the closed position, a valve actuator operable to open the valve member in response to receiving hydraulic fluid from the first hydraulic port, and a hydraulic actuator comprising a hydraulic fluid reservoir and in fluid communication with the casing bore and an annulus defined between the casing and the wellbore and operable to inject hydraulic fluid into the first hydraulic port in response to annulus pressure exceeding casing bore pressure; increasing the annulus pressure so that the annulus pressure is greater than the casing bore pressure, thereby opening the valve member; and drilling the wellbore using the drill string. 2. The method of claim 1, wherein: the casing string further comprises a second hydraulic port, the valve actuator is further operable to close the valve member in response to receiving hydraulic fluid from the second hydraulic port, the hydraulic actuator is further operable to inject hydraulic fluid into the second hydraulic port in response to casing bore pressure exceeding annulus pressure, and the method further comprises: retracting the drill string through the open valve member; and decreasing the annulus pressure so that the casing bore pressure is greater than the annulus pressure, thereby closing the valve member. 3. The method of claim 1, wherein: the hydraulic actuator further comprises a cylinder and a piston disposed in the cylinder, and the hydraulic fluid reservoir is defined between the piston and the cylinder. 4. The method of claim 1, wherein: the hydraulic actuator further comprises a base pipe or shroud and a bladder, and the hydraulic fluid reservoir is defined between the base pipe or shroud and the bladder. 5. A valve system for use in a wellbore, comprising: a downhole deployment valve (DDV), comprising: a housing having a bore formed therethrough and a first hydraulic port formed through a wall thereof; a valve member disposed within the housing and movable between an open position and a closed position, wherein the valve member substantially seals a first portion of the bore from a second portion of the bore in the closed position; and a valve actuator: disposed in the housing, in fluid communication with the first hydraulic port, and operable to open the valve member in response to receiving hydraulic fluid from the first hydraulic port; and a hydraulic actuator: comprising a hydraulic fluid reservoir, connected to the DDV housing and the first hydraulic port, and operable to: receive wellbore pressure and DDV bore pressure, inject hydraulic fluid into the first hydraulic port in response to wellbore pressure exceeding DDV bore pressure. 6. The valve system of claim 5, wherein: the casing string further comprises a second hydraulic port, the valve actuator is in fluid communication with the second hydraulic port and further operable to close the valve member in response to receiving hydraulic fluid from the second hydraulic port, and the hydraulic actuator is connected to the second hydraulic port and further operable to inject hydraulic fluid into the second hydraulic port in response to casing bore pressure exceeding annulus pressure. 7. The valve system of claim 5, wherein: the hydraulic actuator further comprises a cylinder and a piston disposed in the cylinder, and the hydraulic fluid reservoir is defined between the piston and the cylinder. 8. The valve system of claim 5, wherein: the hydraulic actuator further comprises a base pipe or shroud and a bladder, and the hydraulic fluid reservoir is defined between the base pipe or shroud and the bladder. 9. A method of drilling a wellbore, comprising: running a drill string into the wellbore and a bore of a casing string, the casing string comprising: a first hydraulic port, a valve member moveable between an open position and a closed position, wherein the valve member substantially seals a first portion of the casing bore from a second portion of the casing bore in the closed position, a valve actuator operable to open the valve member in response to receiving fluid from the first hydraulic port, and a hydraulic actuator in fluid communication with the casing bore and an annulus defined between the casing and the wellbore and operable to alternate between a first position and a second position, the hydraulic actuator directing fluid from the first hydraulic port into the annulus in the first position, and directing fluid from the casing bore into the first hydraulic port in the second position; increasing the annulus pressure above a predetermined pressure and decreasing the annulus pressure below the predetermined pressure, thereby alternating the hydraulic actuator and opening the valve member; and drilling the wellbore using the drill string. 10. The method of claim 9, wherein: the casing string further comprises a second hydraulic port, the valve actuator is further operable to close the valve member in response to receiving fluid from the second hydraulic port, the hydraulic actuator is further operable to direct fluid from the casing bore into the second hydraulic port in the first position and direct fluid from the second hydraulic port into the annulus in the second position, and the method further comprises: retracting the drill string through the open valve member; and increasing the annulus pressure above the predetermined pressure and decreasing the annulus pressure below the predetermined pressure, thereby alternating the hydraulic actuator and closing the valve member. 11. A valve system for use in a wellbore, comprising: a downhole deployment valve (DDV), comprising: a housing having a bore formed therethrough and a first hydraulic port formed through a wall thereof; a valve member disposed within the housing and movable between an open position and a closed position, wherein the valve member substantially seals a first portion of the bore from a second portion of the bore in the closed position; and a valve actuator: disposed in the housing, in fluid communication with the first hydraulic port, and operable to open the valve member in response to receiving fluid from the first hydraulic port; and a hydraulic actuator: connected to the DDV housing and the first hydraulic port, and operable to: direct fluid from the first hydraulic port into the wellbore in a first position, direct fluid from the DDV bore into the first hydraulic port in a second position, and alternate between the first and second positions in response to wellbore pressure exceeding a predetermined pressure. 12. The valve system of claim 11, wherein: the casing string further comprises a second hydraulic port, the valve actuator is in fluid communication with the second hydraulic port and further operable to close the valve member in response to receiving fluid from the second hydraulic port, and the hydraulic actuator is connected to the second hydraulic port and further operable to direct fluid from the casing bore into the second hydraulic port in the first position and direct fluid from the second hydraulic port into the annulus in the second position.