Remote hydraulic valve control system

A remote hydraulic system for controlling a valve of a wellhead or frac manifold includes a remote hydraulic skid, control skid, and power supply skid. The remote hydraulic skid includes a hydraulic reservoir, a hydraulic pump, an accumulator, a hydraulic manifold operatively coupled to the accumulator, and a hydraulic valve operatively coupled to the hydraulic manifold. The hydraulic valve is operatively coupled to the valve of the wellhead or frac manifold by a hydraulic line. The control skid includes an interface and is operatively coupled to the remote hydraulic skid by a control line. The control skid is adapted to control the actuation of the hydraulic valve. The power supply skid is coupled to the remote hydraulic skid to provide the power necessary to drive the hydraulic pump on the remote hydraulic skid. The remote hydraulic skid is positioned within a hazardous zone around the wellhead, while the control skid and power supply skid are positioned outside of the hazardous zone.

TECHNICAL FIELD/FIELD OF THE DISCLOSURE

The present disclosure relates generally to oilfield equipment and specifically to hydraulic systems for wellhead equipment.

BACKGROUND OF THE DISCLOSURE

During well completions or during workover, an assembly of valves, commonly referred to as a frac tree, is coupled to the wellhead. The valves of the frac tree are used to allow fluid conduits passing into and out of the well to be selectively opened or closed. Additional valves may be positioned on manifolds to transmit frac fluid to the frac tree. During certain operations, such as hydraulic fracturing, the frac tree may contain large pressures within the well. In some cases, valves of the frac tree may be opened and closed hydraulically. However, due to the hazards involved with wellbore operations including, for example, high pressures and potentially flammable atmospheres, the area around the frac tree may be too dangerous for wellsite personnel to remain in the vicinity to manually operate the valves of the frac tree.

SUMMARY

The present disclosure provides for a remote hydraulic system for controlling a valve of a wellhead or frac manifold. The remote hydraulic system may include a remote hydraulic skid. The remote hydraulic skid may include a hydraulic reservoir, a hydraulic pump, and an accumulator.

The remote hydraulic skid may include a hydraulic manifold operatively coupled to the accumulator. The remote hydraulic skid may include a hydraulic valve operatively coupled to the hydraulic manifold. The hydraulic valve may be operatively coupled to the valve of the wellhead or frac manifold by a hydraulic line. The remote hydraulic system may include a control skid. The control skid may include an interface. The control skid may be operatively coupled to the remote hydraulic skid by a control line. The control skid may be adapted to control the actuation of the hydraulic valve. The remote hydraulic system may include a power supply skid coupled to the remote hydraulic skid to provide the power necessary to drive the hydraulic pump on the remote hydraulic skid. The remote hydraulic skid may be positioned within a threshold distance of the wellhead defining a hazardous zone. The control skid and power supply skid may be positioned outside of the hazardous zone.

The present disclosure also provides for a method. The method may include providing a power supply skid and positioning the power supply skid outside of a threshold distance of a wellhead or a frac manifold defining a hazardous zone. The method may include providing a remote hydraulic skid. The remote hydraulic skid may include a hydraulic reservoir, a hydraulic pump, accumulator, and a hydraulic manifold. The remote hydraulic skid may include a hydraulic valve operatively coupled to the hydraulic manifold and having an output port. The method may include positioning the remote hydraulic skid within the hazardous zone. The method may include operatively coupling the hydraulic pump to the power supply skid by a supply umbilical and coupling the output port of the hydraulic valve to a port of a valve of the wellhead or the frac manifold by a hydraulic line. The method may include providing a control skid, the control skid including an interface. The method may include positioning the control skid outside of the hazardous zone and operatively coupling the control skid to the remote hydraulic skid by a control line. The control skid may be adapted to control the actuation of the hydraulic valve. The method may include providing power to the remote hydraulic skid with the power supply skid, actuating the hydraulic valve with the control skid, and providing hydraulic fluid to the valve of the wellhead or the frac manifold.

The present disclosure also provides for a remote hydraulic system for controlling a valve of a wellhead or frac manifold. The remote hydraulic system may include an accumulator skid, the accumulator skid including a hydraulic reservoir and a hydraulic pump. The remote hydraulic system may include a remote hydraulic skid. The remote hydraulic skid may include a hydraulic manifold, the hydraulic manifold operatively coupled to the hydraulic pump of the accumulator skid by a supply umbilical. The remote hydraulic skid may include a hydraulic valve, the hydraulic valve operatively coupled to the hydraulic manifold, the hydraulic valve operatively coupled to the valve of the wellhead or frac manifold by a hydraulic line. The remote hydraulic system may include a control skid, the control skid including an interface, the control skid operatively coupled to the remote hydraulic skid by a control line, the control skid adapted to control the actuation of the hydraulic valve. The remote hydraulic skid may be positioned within a threshold distance of the wellhead defining a hazardous zone. The accumulator skid and control skid may be positioned outside of the hazardous zone.

The present disclosure also provides for a method. The method may include providing an accumulator skid, the accumulator skid including a hydraulic reservoir and a hydraulic pump. The method may include providing a remote hydraulic skid. The remote hydraulic skid may include a hydraulic manifold and a hydraulic valve, the hydraulic valve operatively coupled to the hydraulic manifold, the hydraulic valve having an output port. The method may include positioning the remote hydraulic skid within a threshold distance of a wellhead or a frac manifold defining a hazardous zone. The method may include operatively coupling the hydraulic manifold to the hydraulic pump of the accumulator skid by a supply umbilical. The method may include coupling the output port of the hydraulic valve to a port of a valve of the wellhead or the frac manifold by a hydraulic line. The method may include providing a control skid, the control skid including an interface, positioning the control skid outside of the hazardous zone, and operatively coupling the control skid to the remote hydraulic skid by a control line, the control skid adapted to control the actuation of the hydraulic valve. The method may include providing hydraulic fluid to the remote hydraulic skid with the accumulator skid, actuating the hydraulic valve with the control skid, and providing hydraulic fluid to the valve of the wellhead or the frac manifold.

DETAILED DESCRIPTION

FIG.1depicts wellsite10. Wellsite10may include one or more wells, depicted as wellheads15. One or more of wellheads15may include a valve assembly coupled to wellhead15, depicted as and referred to herein as frac trees20. In some embodiments, wellsite10may also include one or more frac manifolds21, which may be used to supply fluid to frac trees20during hydraulic fracturing operations. Each frac tree20may include one or more valves including, for example and without limitation, master valves22, wing valves24, and swab (or crown) valve26. In some embodiments, one or more valves of frac tree20may be hydraulically operated such that opening and closing of the frac tree20valves may be controlled by remote hydraulic system100. In some embodiments, any such valves, such as swab (or crown) valve26shown inFIG.1A, may include hydraulic valve actuator28. Hydraulic valve actuator28may be adapted to control the opening and closing of swab (or crown) valve26as hydraulic fluid is introduced into opening port31or closing port32as further described below.

Remote hydraulic system100may be positioned at wellsite10. In some embodiments, such as shown inFIGS.1-4, remote hydraulic system100may include power supply skid101, remote hydraulic skid131, and control skid161. In some embodiments, as shown inFIG.1, remote hydraulic skid131may be positioned near frac tree20. In some embodiments, power supply skid101and control skid161may be positioned a distance away from remote hydraulic skid131to, for example and without limitation, allow an operator of control skid161to remain a safe distance away from frac tree20while a wellbore operation is underway. Thus, the operator may be able to operate remote hydraulic system100and thereby control the operations of valves of frac tree20during such a wellbore operation. For example and without limitation, in some embodiments, control skid161may be positioned outside of the defined hazardous zone30. Hazardous zone30may be defined as an area within a threshold distance about frac tree20, wherein the threshold distance may be defined based on anticipated conditions around frac tree20. For example and without limitation, in some embodiments, hazardous zone30may be identified as a Class I or Class II location as defined by the NEC, wherein Class I locations are those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitable mixtures, and Class II locations are those that are hazardous because of the presence of combustible dust. In some embodiments, the threshold distance may also take into account the presence of equipment containing high-pressure fluids including, for example and without limitation, frac tree20and frac manifold21. In some cases, for example and without limitation, hazardous zone30may be defined as extending between 25 and 150 feet from frac tree20and frac manifold21. In some cases, for example and without limitation, hazardous zone30may be defined as extending 50 feet from frac tree20and frac manifold21.

In some embodiments, as depicted inFIGS.2and3, power supply skid101, remote hydraulic skid131and control skid161may be operatively coupled to allow control of valves of frac tree20and frac manifold21. Although a single power supply skid101and a single remote hydraulic skid131are depicted, any number of power supply skids101and remote hydraulic skids131may be used and controlled by a single control skid161without deviating from the scope of the present disclosure.

In some embodiments, power supply skid101may include one or more systems for generating, storing, and supplying electric power to remote hydraulic skid131, control skid161, and any other pieces of wellsite equipment desired. For example and without limitation, in some embodiments, power supply skid101may include one or power supplies including, for example and without limitation, generator181and solar panels183. Generator181may, in some embodiments, be driven by a diesel motor. Because generator181is positioned outside of hazardous zone30, the possible negative effects of operating a heat-generating device and possible fire or explosion hazard proximate frac tree20is reduced. Thus, generator181may be operated without regard for the status of frac tree20including, for example and without limitation, continuously. Similarly, solar panels183may operate to passively generate electricity.

In some embodiments, power supply skid101may include energy storage device185. Energy storage device185may be any device suitable for storing electrical power, such as may be generated by generator181and solar panels183. Energy storage device185may be, for example and without limitation, one or more of batteries, kinetic energy storage devices, or capacitor banks. In some embodiments, power supply skid101may include controller187. Controller187may, in some embodiments, control the operation of power supply skid101including controlling operation of generator181, charging of energy storage device185, conditioning power from solar panels183, and supplying electric power to remote hydraulic skid131and control skid161. In some embodiments, controller187may be positioned in control skid161or may be controlled at least in part by control skid161. In some embodiments, power supply skid101may be connected to main power supply189to, for example and without limitation, use the utility grid for electric power to operate remote hydraulic system100or charge energy storage device185.

In some embodiments, remote hydraulic skid131may include hydraulic fluid reservoir103. Hydraulic fluid reservoir103may be a tank used to store hydraulic fluid104for use in remote hydraulic system100. Remote hydraulic skid131may include one or more pumps105positioned to pump hydraulic fluid104from hydraulic fluid reservoir103to charge accumulator bottles108. In some embodiments, pumps105may be, for example and without limitation, positive displacement pumps such as piston pump, screw pump, or progressing cavity pump. Pumps105may transfer hydraulic fluid into supply line107.

In some embodiments, pumps105may be driven by electric motors106. Electric motors106may be explosionproof electric motors as understood in the art. By selecting explosionproof electric motors, operation of pumps105by electric motors106within hazardous zone30may be safer than the operation of other pump arrangements including, for example, diesel motors, due to the reduced likelihood of, for example and without limitation, ignition of flammable gases within hazardous zone30. Electric motors106may be supplied with electric power from power supply skid101via umbilical191. In other embodiments, pumps105may be pneumatically driven, in which case rather than electric power, pneumatic power is supplied from power supply skid101.

In some embodiments, with reference toFIGS.2-4, remote hydraulic skid131may include relief valve109, which may be used to avoid overpressurization of accumulator bottles108. In some embodiments, remote hydraulic skid131may include filter111positioned to filter hydraulic fluid104as it passes through remote hydraulic skid131.

In some embodiments, remote hydraulic skid131may include hydraulic manifold133. Hydraulic manifold133may receive hydraulic fluid from accumulator bottles108. Hydraulic manifold133may be operatively coupled to control valves135a-d. In some embodiments, for example and without limitation, control valves135a-dmay be pneumatically, hydraulically, or electromechanically actuated via hydraulic control valves such as a directional control shuttle valve. Each of the control valves135a-dmay be operatively coupled to an opening and closing port of a valve of frac tree20(or frac manifold21as discussed above), shown inFIGS.3,4, such as master valve22, wing valves24, and swab valve26, via a respective hydraulic line137a-h. In some embodiments, when one or more of control valves135a-dare opened, high-pressure hydraulic fluid from hydraulic manifold133may flow through the respective hydraulic line137a-h and into the corresponding valve of frac tree20, thereby causing the respective valve of frac tree20or frac manifold21to open or close.

Because umbilical191carries only electric power, the complexity associated with rigging up remote hydraulic system100and any adverse effects caused by running individual hydraulic lines to control valves135a-dmay be reduced. Additionally, because remote hydraulic skid131includes hydraulic pumps105, hydraulic fluid reservoir103, hydraulic manifold133, and control valves135a-d, without being bound to theory, the pressure drop between hydraulic manifold133or accumulator bottles108and frac tree20may be reduced from the amount of pressure drop associated with multiple hydraulic lines that extend outside of hazardous zone30, which may allow for a reduction in the amount of hydraulic hose that needs to be installed and retrieved, increase the responsiveness of valves of frac tree20and reduce pressure demand on accumulator bottles108.

In some embodiments, each control valve135a-dmay be controlled by control skid161. Control skid161may include interface163to allow an operator to control the operation of control valves135a-d. In some embodiments, interface163may include one or more manual controls. In other embodiments, interface163may include one or more digital controls including, for example and without limitation, a touchscreen interface as discussed further herein below. In some embodiments, control skid161may electrically, pneumatically, or hydraulically control the actuation of control valves135a-dvia one or more corresponding control lines165a-d. In some embodiments, for example and without limitation, control skid161may electrically actuate control valves135a-d, which may be pneumatically or hydraulically actuated. In some embodiments, control skid161may control the operation of pump105.

Although four control valves135a-dare depicted inFIG.3, remote hydraulic skid131may include any number of control valves within the scope of the present disclosure. Additionally, althoughFIG.3depicts only a single frac tree20, remote hydraulic skid131may be configured to control the valves of multiple frac trees20within the scope of the present disclosure.

In some embodiments, as shown inFIG.5-8, remote hydraulic system200may be positioned at wellsite10. In such an embodiment, remote hydraulic skid231may be positioned near frac tree20. In some embodiments, accumulator skid201, transfer pump skid253, and control skid261may be positioned a distance away from remote hydraulic skid231to, for example and without limitation, allow an operator of control skid261to remain a safe distance away from frac tree20while a wellbore operation is underway. Thus, the operator may be able to operate remote hydraulic system200and thereby control the operations of valves of frac tree20during such a wellbore operation. For example and without limitation, in some embodiments, control skid261may be positioned outside of the defined hazardous zone30.

In some embodiments, as depicted inFIGS.6and7, accumulator skid201, remote hydraulic skid231, transfer pump skid253, and control skid261may be operatively coupled to allow control of valves of frac tree20and frac manifold21. Although a single accumulator skid201and a single remote hydraulic skid231are depicted, any number of accumulator skids201, remote hydraulic skids231, and transfer pump skids253may be used and controlled by a single control skid261without deviating from the scope of the present disclosure.

In some embodiments, accumulator skid201may include hydraulic fluid reservoir203. Hydraulic fluid reservoir203may be a tank used to store low or no pressure hydraulic fluid204for use in remote hydraulic system200. Accumulator skid201may include one or more pumps205positioned to charge accumulator bottles208of accumulator skid201. In some embodiments, pumps205may be, for example and without limitation, positive displacement pumps such as piston pump, screw pump, or progressing cavity pump. Pumps205may output hydraulic fluid into supply umbilical207for supply to remote hydraulic skid231as further discussed below.

In some embodiments, accumulator skid201may be positioned near to remote hydraulic skid231within wellsite10such that the length of supply umbilical207may be reduced. By reducing the length of supply umbilical207, without being bound to theory, the pressure drop along supply umbilical207may be reduced from the amount of pressure drop associated with a supply umbilical that extends outside of hazardous zone30.

In other embodiments, such as shown inFIG.5, accumulator skid201may be positioned outside of hazardous zone30. By using a single, larger supply umbilical207as opposed to a plurality of smaller hydraulic lines directly connecting between an accumulator skid positioned outside hazardous zone30and frac tree20, the total pressure drop for each line, the complexity of the system, the time required to rig up or down the system, and the weight of the system may be reduced.

Additionally, by locating remote hydraulic skid231at a location nearer to frac tree20, the response time of the valve may be reduced as compared to a system where remote hydraulic skid231is positioned outside of hazardous zone30as there is a shorter distance for the hydraulic fluid to travel and there is less fluid resistance in the hose.

In some embodiments, with reference toFIGS.6and7, accumulator skid201may include relief valve209, which may be used to avoid overpressurization of accumulator bottles208. In some embodiments, accumulator skid201may include filter211positioned to filter hydraulic fluid204as it passes through accumulator skid201.

In some embodiments, remote hydraulic skid231may include hydraulic manifold233. Hydraulic manifold233may receive hydraulic fluid from supply umbilical207. Hydraulic manifold233may be operatively coupled to control valves235a-d. In some embodiments, for example and without limitation, control valves235a-dmay be pneumatically, hydraulically, or electromechanically actuated hydraulic control valves such as a directional control shuttle valve. Each of the control valves235a-dmay be operatively coupled to an opening and closing port of a valve of frac tree20(or frac manifold21as discussed above), shown inFIG.7as master valve22, wing valves24, and swab valve26, via a respective hydraulic line237a-h. In some embodiments, when one or more of control valves235a-dare opened, high-pressure hydraulic fluid from hydraulic manifold233may be allowed to flow through the respective hydraulic line237a-hand into the corresponding valve of frac tree20, thereby causing the respective valve to open or close.

In some embodiments, remote hydraulic skid231may include return reservoir239. Return reservoir239may, in some embodiments, receive hydraulic fluid that returns from a valve of frac tree20when the valve is opened or closed. In some embodiments, return reservoir239may be fluidly coupled to transfer pump skid253via return umbilical255. Transfer pump skid253may include transfer pump257, positioned to pump hydraulic fluid from return reservoir239to hydraulic fluid reservoir203.

In some embodiments, each control valve235a-dmay be controlled by control skid261. Control skid261may include interface263to allow an operator to control the operation of control valves235a-d. In some embodiments, interface263may include one or more manual controls including, for example and without limitation, buttons, dials, or other components. In other embodiments, interface263may include one or more digital controls including, for example and without limitation, a touchscreen interface as discussed further herein below. In some embodiments, control skid261may electrically, pneumatically, or hydraulically control the actuation of control valves235a-dvia one or more corresponding control lines265a-d. In some embodiments, for example and without limitation, control skid261may electrically actuate control valves235a-d, which may be pneumatically or hydraulically actuated. In some embodiments, control skid261may control the operation of pump205and transfer pump257.

Although four control valves235a-dare depicted inFIG.7, remote hydraulic skid231may include any number of hydraulic control valves within the scope of the present disclosure. Additionally, althoughFIG.7depicts only a single frac tree20, remote hydraulic skid231may be configured to control the valves of multiple frac trees within the scope of the present disclosure.

In some embodiments, remote hydraulic system200may include accumulator skid201, remote hydraulic skid231, transfer pump skid253, and control skid261. With reference toFIGS.5-8, in order to operate remote hydraulic system200at wellsite10, accumulator skid201, remote hydraulic skid231, transfer pump skid253, and control skid261may be transported to wellsite10. Remote hydraulic skid231may be positioned relatively close to wellhead15with which remote hydraulic system200will be utilized, while accumulator skid201, transfer pump skid253, and control skid261may be positioned a distance away from wellhead15outside of hazardous zone30. Supply umbilical207and return umbilical255may be operatively coupled to remote hydraulic skid231from accumulator skid201and transfer pump skid253, respectively. Hydraulic lines237a-hmay be operatively coupled between control valves235a-dand opening ports31and closing ports32of valves of frac tree20. Control lines265a-dmay be operatively coupled between control skid261and remote hydraulic skid231. Pump205may be activated to charge accumulator bottles208such that hydraulic fluid may be supplied to remote hydraulic skid231. As desired, one or more of control valves235a-dmay be opened to supply hydraulic fluid to the valves of frac tree20in order to open or close valves of frac tree20using control skid261.

FIG.9depicts an example of graphical user interface300for control skid161/261consistent with at least one embodiment of the present disclosure. In some embodiments, graphical user interface300may be adapted for use in a digital, touchscreen-based embodiment of interface163. GUI300may include one or more controls adapted to allow an operator to control the operation of remote hydraulic system100/200. In some embodiments, GUI300may provide one or more screens for user interaction with remote hydraulic system100/200. For example and without limitation, in some embodiments, GUI300may include status overview display300aas shown inFIG.9, wherein visual indicators303display the status of valve of frac tree20. In some embodiments, GUI300may be used to control multiple frac trees20. In some embodiments, elements of GUI300as discussed herein may be color-coded to allow for association with particular frac trees20or otherwise assist with visual identification thereof.