Patent Application
20190112888
Not Applicable
Not Applicable
This disclosure relates to the field of electrical and other type of conduit (hydraulic, pneumatic etc.) passed through a wellhead or similar surface-deployed well valve system.
Many oil and gas wells (especially higher pressure wells) have a well closure valve assembly (“Christmas tree” or “Xmas tree”) within a surface wellhead assembly. While Xmas trees come in many different variations and are made by several different manufacturers they are fundamentally similar in nature in containing surface valves and fittings to perform specific functions. One of the important features on a Xmas tree is a master valve to safely shut-in a well in the event of an emergency. Typically, shut-in is performed using an Emergency Shut Down (ESD) process which automatically closes the master valve using an attached actuator, such as an electric, hydraulic or pneumatically powered actuator. Therefore, it is important that a well can be safely shut in using the actuated master valve.
Modifications and changes to the Xmas tree and related fittings and flow lines are undesirable as the assembly is certified to industry and/or governmental safety standards and re-certification or acceptance of different safety systems can take excessive time and be very expensive.
In most existing applications conduit (cable, control line tubing, coil tubing, etc.) is not permanently left protruding through the Xmas tree as this would prevent the master valve from closing. Where cable passage through a Xmas tree is required such as wireline or coil tubing intervention operations, additional components (for example spool pieces) are assembled to the Xmas tree or wellhead to provide the required safety barriers.
In some applications such as cable or coil tubing deployed downhole pumps, insert gas lift, insert safety valves etc. it is required to have conduits and/or cables permanently placed inside the production tubing which need to exit through the Xmas tree. While there are some known devices which can obtain such functionality, such known solutions all have undesirable features which may make them unacceptable for safety or cost reasons.
Considerations in providing a feed through for a cable or tubing include that: (i) retaining existing Xmas tree safety functionality is desirable. In particular the master valve needs to be automatically (actuated) closed in the event of an ESD; (ii) it is undesirable to modify the Xmas tree components. An exception to the foregoing is around the “swab” valve usually at the top of the Xmas tree as this is the entry port already used for well interventions; (iii) it is undesirable to adjust flowlines attached to the wellhead because re-certification can be very expensive.
An aspect of the present disclosure relates to a wellhead valve assembly feedthrough for a cable or conduit, comprising:
In some example operations, the moveable upper connector may be extended and retracted to selectively make and break a connection to accommodate required operations associated with the wellhead valve assembly and/or associated wellbore.
The wellhead valve assembly feedthrough may comprise an actuator, such as a linear actuator, coupled to the upper connector. Operation of the actuator may provide movement to the upper connector. The linear actuator may comprise at least one of an electrically, pneumatically and hydraulically operated actuator.
The lower connector may be disposed below a master valve in the wellhead assembly. The moveable upper connector may be moveable through the master valve. The moveable upper connector may be retractable to a position above the master valve. In some examples the moveable upper connector may be retractable to disconnect from the lower connector prior to operation, for example a closing operation, of the master valve.
The master valve may comprise a power operated actuator. In such an arrangement the master valve may be defined as an actuated master valve. The power operated actuator may comprise at least one of an electrical, pneumatic and hydraulic powered actuator.
In some examples the master valve may comprise a manually operated valve.
The lower connector may be disposed below an upper master valve in the wellhead valve assembly. The moveable upper connector may be moveable through the upper master valve. In some examples the moveable upper connector may be retractable to disconnect from the lower connector prior to operation, for example a closing operation, of the upper master valve. The upper connector may be retractable to above the upper master valve.
The upper master valve may comprise a power operated actuator. In such an arrangement the upper master valve may be defined as an actuated master valve. The power operated actuator may comprise at least one of an electrical, pneumatic and hydraulic powered actuator.
The lower connector may be disposed below a lower master valve in the wellhead valve assembly. The moveable upper connector may be moveable through the lower master valve. In some examples the moveable upper connector may be retractable to disconnect from the lower connector prior to operation, for example a closing operation, of the lower master valve. The upper connector may be retractable to at least above the lower master valve.
The lower master valve may comprise a manually operated actuator. However, in other examples the lower master valve may comprise a power operated actuator.
The lower connector may be disposed in a tubing hanger in the wellhead valve assembly. In some examples the lower connector may be disposed above a flowline outlet in the tubing hanger.
The sealed exit may comprise a sealed exit spool. The exit spool may be disposed above a swab valve on top of the wellhead valve assembly. The exit spool may be disposed between a swab valve on top of the wellhead and a least one wing valve in the wellhead.
The sealed exit may comprise a crown plug.
The segment of conduit or cable may comprise a spring-shaped segment. The spring shaped segment may assist in movement, for example retraction, of the upper connector following disconnection from the lower connector. For example, when the lower and upper connectors are in a connected state the spring-shaped segment may be extended in an “energised” state, such that following disconnection the effect of elastic recovery may cause or assist retraction of the lower connector.
The segment of cable or conduit may comprise a plastic portion. Such an arrangement may facilitate easier shearing (for example by a valve such as a master valve) in the event of the segment of cable or conduit not retracting sufficiently.
The lower connector may be mounted, for example suspended, in the wellhead valve assembly. In such an arrangement the cable or conduit may be supported by or suspended from the wellhead valve assembly.
The cable or conduit may extend within the wellbore to provide power and/or communication to/from a downhole location. In one example the cable or conduit may be coupled to a submersible pump deployed at a selected depth in the wellbore.
The wellhead valve assembly may comprise a Christmas tree, such as a vertical Christmas tree, horizontal Christmas tree or the like.
The wellhead valve assembly may facilitate redress and/or change-out of one or more valves contained therein. In some examples complete change-out of one or more valves may be permitted. In some examples one or more parts of a valve may be exchanged, for example all or part of valve internals may be exchanged.
The cable or conduit, for example the segment of the cable or conduit, may be coupled or otherwise in communication with an Emergency Shutdown (ESD) system. The ESD system may de-energise the cable or conduit prior to any disconnection event. Such an arrangement may minimise any risk associated with disconnection and/or shearing while the cable or conduit is energised, for example with electrical current, hydraulic pressure, pneumatic pressure and the like.
An aspect of the present disclosure relates to a method for making and/or breaking a connection between upper and lower connectors within a wellhead valve assembly feedthrough. The method may comprise operating a wellhead valve assembly feedthrough according to any other aspect.
An aspect of the present disclosure relates to a wellhead valve assembly feedthrough for a cable or conduit, comprising:
The actuator may be a linear actuator. The linear actuator may comprise at least one of an electrically operated, a pneumatically operated and a hydraulically operated actuator.
The exit spool may be disposed above a swab valve on top of the wellhead. The exit spool may be disposed between a swab valve on top of the wellhead and a least one wing valve in the wellhead.
The master valve may comprise a power operated actuator. The power operated actuator may comprise at least one of an electrical, pneumatic and hydraulic powered actuator.
The lower connector may be disposed below an upper master valve in the wellhead valve assembly. The upper connector may be moveable through the upper master valve. In some examples the moveable upper connector may be retractable to disconnect from the lower connector prior to operation, for example a closing operation, of the upper master valve. The upper connector may be retractable to above the upper master valve.
The upper master valve may comprise a power operated actuator. In such an arrangement the upper master valve may be defined as an actuated master valve. The power operated actuator may comprise at least one of an electrical, pneumatic and hydraulic powered actuator.
The lower connector may be disposed below a lower master valve in the wellhead valve assembly. The upper connector may be moveable through the lower master valve. In some examples the moveable upper connector may be retractable to disconnect from the lower connector prior to operation, for example a closing operation, of the lower master valve. The upper connector may be retractable to at least above the lower master valve.
The lower master valve may comprise a manually operated actuator. However, in other examples the lower master valve may comprise a power operated actuator.
The segment of conduit or cable may comprise a spring-shaped segment.
An aspect of the present disclosure relates to a wellhead feedthrough for a cable or conduit, comprising:
An aspect of the present disclosure relates to a wellhead valve assembly feedthrough for a cable or conduit, comprising:
The plastic cable or conduit may be shearable by the master valve when the master valve is operated by at least one of an electric, a pneumatic and an hydraulic actuator.
The master valve may comprise a lower master valve. The master valve may comprise an upper master valve.
An aspect of the present disclosure relates to a wellhead valve assembly feedthrough for a cable or conduit, comprising:
These and other aspects of the present disclosure will now be described, by way of example only, with reference to the Figures, in which:
Some examples of the electrical cable 102 may be in the form of a tubing encapsulated cable (TEC). An electrical power take-off and signal decoding sub 106 may be disposed intermediate the cable head 104 and the electric motor 108. The electrical power take-off and signal decoding sub 106 may include circuitry (not shown separately) of types known in the art for controlling the operating speed of the electric motor 108 and its direction of rotation in the present example. The sub 106 may also have circuits (not shown separately) for decoding command signals to operate valves in a valve sub 118. The electric motor 108 may be any type known in the art used in ESP systems, for example, a multi-phase induction motor. Depending on the type of pump used, a rotational output of the electric motor 100 may be coupled through a torque converter 110. If used, the torque converter 110 may reduce the rotational speed and increase the torque at its output relative to its input, or vice versa. Rotational output of the torque converter 110 (if used) may pass through a protector/seal assembly 112 and a positive displacement pump 116 such as a progressive cavity pump. The type of pump is not intended to limit the scope of the present disclosure. A fluid discharge for the pump 116 is shown at ports 5. In this respect ports 5 may function as a pump discharge when the pump 116 is operated in a normal or forward direction of rotation. However, when the pump 116 is operated in a reverse direction the ports 5 may function as a pump inlet. The pump 116 may also be a centrifugal pump which does not have a torque converter.
A flow bypass 4 may be disposed below the pump 116. The valve sub 118 may be disposed below the flow bypass 4 and may include valves that may be remotely operated to cause selective operation of various components of the ESP system 100 as required.
In one example of a cable/conduit feedthrough, as shown in
In the present example an additional spool 52 may be disposed below the swab valve 51 and above the wing valves 54. A cable outlet 53 in the spool 52 includes an upper conduit linear actuator 53A and a side connector 53C. The upper conduit linear actuator 53A may be installed through the swab valve 51 such that an upper electrical connector 56A would be disposed just above the actuated master valve 55B when the upper conduit linear actuator 53A is deactivated. A lower electrical connector 56B may be disposed just below the manually operable master valve 55A. The gap between the two connectors 56A, 56B may be approximately the height of both master valves 55A, 55B. When actuated, the upper conduit linear actuator 53A would extend the upper electrical connector 56A and mate the electrical connectors 56A, 56B. If the upper conduit linear actuator 53A is powered down, a spring (not shown separately) may provide passive biasing force to disengage the connectors 56A, 56B and retract the upper connector 56A to its rest position just above the actuated master valve 55B. The actuated master valve 55B may then be closed, for example in the event of an ESD. In this respect, an associated ESD system may shut-down or de-energise the cable prior to disconnection.
The portion of the conduit or cable traversing the actuated master valve 55B may be made from plastic or other relatively soft material such that it could be sheared by the actuated master valve 55B in the event the connectors 56A, 56B do not disengage correctly. Also the linear actuator assembly 53A could be in a controlled environment to improve reliability. The connectors 56A, 56B may be wet mate-able although in most applications a moderate IP (Ingression Protection) rating would suffice. The linear actuator 53A could be powered by electricity, hydraulics or pneumatics. An example of an electric linear actuator that may be used in some examples may be a model 2000N electric linear actuator (stroke up to 300 mm) sold by SKF Solution Factory, 3443 North Sam Houston Parkway West Building 5 Houston, Tex. 77086. The linear actuator 53A may be modified for the space and operating environment requirements within the wellhead Xmas tree 50.
The example shown in
If it is not possible to add a spool (e.g., 52) below the swab valve 51, which may be the case for solid body Xmas trees, the spool 52 and an additional swab valve (not shown) could be connected above the existing swab valve 51, which would be kept open during ordinary ESP operations.
Some possible benefits of the example shown in
Another example may comprise a telescopic linear actuator 52A above the swab valve 51 as illustrated in
When operated in one direction the telescopic linear actuator 52A would deploy a conduit with connector through the Xmas tree to mate with the TEC connector and hanger 102A. When operated in the other direction the telescopic linear actuator 52A would disconnect and recover the conduit and connector back into the actuator sub. The linear actuator 52A could be fabricated using relatively soft materials such as plastic so that in the event of failure, the actuated master valve 55B can easily shear the portions of the actuator and conduit passing through the master valve 55B and seal the well.
Other examples may require the need for some intervention in the well after the master valve 55B has been actuated. Referring to
Referring to
Another example is shown in
Another possible example is shown in
The tubing hanger 174 may comprise a side exit flow line 54A from which well fluids may be discharged.
A lower crown plug 172 may be sealingly engaged in an interior through bore in the tubing hanger 174. An ESP cable 102 or other conduit may be coupled to a suspension device 166 supported in the tubing hanger 174 above the flow line 54A. An upper crown plug 168 may be sealingly engaged in the through bore above the lower crown plug 172. Electrical, hydraulic and/or pneumatic connection between the lower crown plug 172 and the upper crown plug 168 may be made or released by a telescoping joint 162 which may include suitable electrical and or fluid connectors, e.g., a wet mate-able connector 164, to establish electrical and or fluid communication between the upper crown plug 168 and the lower crown plug 172. In examples wherein the connection through the tree body 50A is an electrical cable (ESP cable 102), a dry mating connector 160 may be disposed on the upper end of the upper crown plug 168 to enable an electrical “pigtail” 102A to be connected and disconnected from the ESP cable 102 as required.
While the present disclosure has been described with respect to a limited number of examples, those skilled in the art, having benefit of this disclosure, will appreciate that other examples can be devised which do not depart from the scope of the claims. Accordingly, the scope of the present disclosure should be limited only by the attached claims.
Continuation of International Application No. PCT/GB2017/051721 filed on Jun. 13, 2017. Priority is claimed from U.S. Provisional Application No. 62/349,685 filed on Jun. 14, 2016. Both the foregoing applications are incorporated herein by reference in their entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62349685 | Jun 2016 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/GB2017/051721 | Jun 2017 | US |
| Child | 16219804 | US |
