CEMENT HEAD WITH MOVABLE PLUG CAGE AND PRESSURE BALANCED PLUG LAUNCH INDICATOR
A cement head is disclosed that includes a cement head body that houses a moveable cage which protects a cement plug until the cement plug is released into a cement flow path. The cage is moveable between a first position in which cement slurry flows around the cage, and a second position in which cement slurry flows through the cage to facilitate launch of the cement plug into a wellbore. The cage may include a lifting device to assist with moving the cage from the second position to the first position after launch of the cement plug. The cement head may be a modular design that includes multiple cement head bodies, and may also include a pressure balanced plug launch indicator and torque keys.
The accompanying drawings are part of the present disclosure and are incorporated into the specification. The drawings illustrate examples of embodiments of the disclosure and, in conjunction with the description and claims, serve to explain various principles, features, or aspects of the disclosure. Certain embodiments of the disclosure are described more fully below with reference to the accompanying drawings. However, various aspects of the disclosure may be implemented in many different forms and should not be construed as being limited to the implementations set forth herein. Like numbers refer to like elements, but are not necessarily the same or identical elements throughout.
This disclosure generally relates to an improved cement head for launching cementing plugs and/or wiping devices for well cementing operations.
In oil well cementing operations, cementing plugs are placed at the beginning and/or end of a predetermined amount of cement slurry being pumped into a wellbore. Prior to placement, the cementing plugs are housed in a cement head that may include a stationary cage or container for protecting the plug prior to release. Some conventional cement heads may include double or triple chambers for receiving multiple plugs within a single cement head body. Conventional cement heads may also require many additional components, such as manifolds to control the flow of cement through the cement head and biasing mechanisms to introduce the cementing plugs into the cement slurry flow path. Biasing mechanisms for introducing a cement plug, however, are susceptible to malfunction due to blockage by build-up of the cement slurry in the cement head and/or corrosive failure in harsh environments.
Conventional cement heads may also include tattle tales to indicate that the cement plug has been launched from the cement head. Tattle tale assemblies may include both internal components that are located within the cement head body and external components which are located outside the cement head body. Tattle tale assemblies may be exposed to high pressures within the cement head body. Because of the pressure differential experienced across the tattle tale assembly, conventional tattle tale assemblies are susceptible to malfunction or failure.
Embodiments of the cement head of the present disclosure are configured to overcome the above issues and may include a moveable internal cage for introducing the cementing plug into a wellbore. The cement head of the present disclosure may also be equipped with a pressure balanced plug launch indicator including a tattle tale assembly that may be less susceptible to malfunction in environments where a pressure differential is present across the cement head.
In accordance with an embodiment of the disclosure, a cement head cap may be attached to one end of the cement head. Cement slurry may enter through an opening in the cap and may be channeled around the moveable internal cage by an internal lid. In some exemplary embodiments, the opening in the cap may include lateral ports that are configured to introduce cement slurry from a lateral side of the cement head. A flow path of the cement slurry may be diverted and/or redirected by the moveable internal cage which is located within the cement head body and which is moveable between at least two positions. The movable cage may house at least one cement plug installed therein and may be held in a first position in close proximity to the cap and/or lid, at least in part, by a plug release mechanism. In the first position, the cement slurry is channeled around the cage along an initial operating flow path such that the cage protects the cement plug from unnecessary contact with the cement slurry. A top end of the cage may be include an expanded or flanged offset portion, for example. The offset portion may redirect the cement slurry from the initial operating flow path located around the cage, to a launching flow path that goes through the cage to launch the cement plug.
The plug release mechanism may include, as a non-limiting example, a flapper that is located at a lower end of the cage and extends transversely across a bottom of the cage to hold the cage in the first position. When the flapper is released, the flapper is allowed to swing/pivot in a downward direction and the cage is allowed to move to a second position away from the cap and/or lid. When the cage is in the second plug release position and the cement slurry has been redirected through the cage, the cement slurry flows at least partially along an upper surface of the cement plug to create a force to move the cement plug out of the cement head body and into the wellbore.
Release of the cement plug from the cage actuates the pressure balanced plug launch indicator which includes multiple sealing systems and is configured to prevent malfunction in environments with differential pressures that act on the components of the plug launch indicator. After release of the cement plug, in some embodiments a lifting device, such as a lever or handle, may be operated to move the cage from the second position back to the first position to prepare the cement head for receipt of another cement plug. In other embodiments, the cage may include a return mechanism, such as a spring assembly, that automatically returns the cage to the first position. The disclosure, however, is not intended to be limited by these exemplary embodiments and other configurations for how the cage is moved from the second position back to the first position are contemplated. As non-limiting examples, other configurations may include push button assemblies, mechanisms that automatically return the cage upon release of the cement plug, etc.
Main components of the cement head, such as the cement head body, cap, and adapter, may be rotationally locked with respect to each other by, for example, a key. The key may allow the cement head to be used on top drive applications where rotation of the work string is desired. The cement head main components may also include breech lock buttress profile connections for high capacity hook strength applications.
In applications that require multiple plugs and/or wiping devices to be launched into the well casing, the cement head in accordance with the disclosure may be configured to include modular components that permit stacking of the cement head components. This arrangement allows multiple plugs to be arranged for sequential release using multiple modular-type cement heads, and eliminates the need to stock various types and/or configurations of cement heads.
Although this disclosure describes a cement head that may be used in wellbore cementing applications, the present invention is not intended to be limited to the disclosed apparatuses or environments and modifications are considered to be within the scope of this disclosure. For example, the disclosed cement head may be implemented in any environment that may require plugging operations.
As shown in
A tattle tale indicator 14A and a tattle tale actuator 14B may be arranged on the tattle tale body 12 to notify an operator when the cement plug 101 has been launched. The tattle tale actuator 14B may be installed on a central region of the tattle tale body 12 in a launch path of the cement plug 101, and the tattle tale indicator 14A may be installed at one or both ends of the tattle tale body 12.
The pivot pin 11G (
The redirected cement slurry 200 flows through the space 204 and into the gap 73 between the lid 7 and the cement plug 101, and pushes the cement plug 101 downstream and out of the cage 11. As shown in
In accordance with embodiments of the disclosure and as described above, the flow path of the cement slurry 200 entering the cement head 100 is directed around the cage 11 when the cage 11 is in a first position (
When the cement plug 101 is launched, the cement plug 101 contacts and rotates the tattle tale actuator 14B located in the bore 1A of the cement head body 1. Rotation of the tattle tale actuator 14B by the cement plug 101 rotates the tattle tale body 12 around its longitudinal axis, which moves the tattle tale indicator 14A from the initial pre-launch position (
As shown in
In a non-limiting example in accordance with embodiments of the disclosure, when the release pin 17 is to be actuated, the pin puller knob 24 may be moved in an axial direction of the plug launch mechanism 15 to release the lock pin 23 from slots in the pin puller crown 21. The pin puller knob 24 may then be rotated and released to fix the lock pin 23 in a disengaged position which allows the bonnet 22 and the nut 19 to be rotated. The bonnet 22 may be operated by, for example, two right hand turns applied to the bonnet 22. This rotation causes the release pin 17 to be rotated into the nut 19 and, thus, retracted from the bore 1A of the cement head body 1. In other embodiments, the release pin 17 may be actuated by other suitable mechanical, electrical, or pneumatic device such as, for example, a push button release mechanism.
The cement head body 1, the cap 6, and the casing adapter 9 may be rotationally locked with respect to each other by keys 40 which are secured in place by screws 41, as shown in
During operation, the cage 111 is initially located in the running position shown in
When the release pin 17 is retracted, the cage 111 slides downward along pins 108 to the position shown in
To reposition the cage 111 after releasing the cement plug 101, the ported cap 65 is removed from the cement head body 151, and the handle 111A is rotated upward as shown in
The cage handle 111A allows “recocking” or repositioning of the cage 111 without removing the cage 111 from the cement head body 151. In an exemplary embodiment, a three-quarter or 270 degree turn of the cage handle 111A repositions the cage 111 to an initial running position. However, this embodiment is not intend to limit the disclosure, and it is within the scope of this disclosure that any type of “handle,” “lever,” or device that can lift, move, or reposition the cage 111 in the running position without removal of the cage 111 from the cement head body 151 may be used.
As shown in
In the exemplary arrangement shown in
In operation, cement is pumped into the ports 66 of the ported cap 65 as described above with respect to cement head 150. Cement initially flows around both the cage 111 and the cage 111′. When the downstream cement plug 101′ is to be launched, downstream plug launching mechanism 15′ is actuated and the downstream cage 111′ is allowed to move downward. Cement then flows through the downstream cage 111′, causing the downstream cement plug 101′ to be launched, while the upstream cement plug 101 remains in the initial operating/running position. The upstream cement plug 101 may be launched thereafter, as described above.
The torque key 140 is slidable in an axial direction of the cement head 150 within a slot 67 that may be machined into an outer surface of the ported cap 65. The torque key 140 may slide along a pin 68A located in protrusions 68 of the ported cap 65. Rotational or pivotal movement of the torque key 140 around the pin 68A is limited by the protrusions 68 and by the close proximity of the torque key 140 with a bottom of the slot 67. The torque key 140 may also include a retaining screw 141 for preventing release of the torque key 140 from the cement head body 151. The cement head body 151 may include a cooperating slot or pocket 151C which may have a hole or recess 151D in a bottom surface for receiving and locking the retaining screw 141 in a locked position.
When the ported cap 65 is to be connected to the cement head body 151, the ported cap 65 is rotated relative to the cement head body 151 until the torque key 140 aligns with pocket 151C. In this position, the retaining screw 141 is in a first position (
Although not shown, the torque key 140 may include a biasing device to assist with movement of the torque key 140 into the locked or latched position and/or to automatically move the torque key 140 to the locked/latched position shown in
Cage 211 may operate in a manner that is similar to that of cage 11 and/or cage 111. For example, as shown in
In the second position, a cement flow path between the cage 211 and the cement head body 151 is blocked by a flange 211A of the cage 211, and cement slurry is redirected through an opening at the top of the cage 211. Cement then flows through the cage 211 and pushes the cement plug 101 (not shown) out of the cage 211 and through the cement head body 151. As described above, passage of the cement plug 101 through the cement head body 151 causes the tattle tale actuator 14B and the tattle tale indicator 14A to rotate, providing a visual indication to an operator that the cement plug 101 has been released.
In the disclosed embodiment, cage 211 may be configured to cooperate with an automatic lifting device, such as a biasing assembly 270, to automatically move the cage 211 from the second position (
In
Disclosed embodiments of the cap 265 and the biasing assembly 270 are not intended to be limited to the embodiments described herein. Other arrangements that are configured to cooperate to automatically move the cage are considered to be within the scope of the disclosure. In addition, the cage 211 may be configured such that automatic movement of the cage 211 may occur with or without intervention of an operator. Further, the biasing assembly 270 may also include a sleeve or other device (not shown) that is positioned between the spring 275 and the cement slurry flow path to prevent clogging/sticking of the spring 275.
In an example implementation of an embodiment, the cap 6 and the casing adapter 9 are connected to the cement head body 1 by, for example, a stabbed, threaded, or other mechanical connection. The keys 40 are installed on and secured to the cement head body 1, the cap 6, and the casing adapter 9 to prevent relative rotation of the components. The cement head 100 is connected to a cement slurry source (not shown) and a work string (not shown). In the initial operating position, the cage is in the first, upward position, the plug launch indicator 10 is in a pre-launch position with an end of the tattle tale actuator 14B extended into the bore 1B of the cement head body 1, and the tattle tale indicator 14A is in a position that is adjacent the cement head body 1. In the first or initial operating position, the cement slurry 200 flows through the cap 6, is directed by the lid 7 through the ports 71, flows around an outside of the cage 11, and exits the casing adapter 9.
When the cement plug 101 is to be released, the release pin 17 is actuated and withdrawn from an extended position where the release pin 17 is in contact with the flapper 11D. The flapper 11D is released and swings downward, allowing the cage 11 to move freely. The cage 11 slides along the pins 8 which are located in the respective slots 11F to a second position where pins 8 are in contact with an upper surface of the respective slots 11F to hold the cage 11 in the second position.
In the second position, the expanded top end 11A of the cage 11 blocks and redirects flow of the cement slurry 200 through a central bore of the cage 11 where the cement plug 101 is located. Flow of the cement slurry 200 pushes the cement plug 101 downstream toward the casing adapter 9. As the cement plug 101 travels through the inner portion 11C of the cage 11, the cement plug 101 contacts and rotates the tattle tale actuator 14B such that the tattle tale body 12 also rotates. Rotation of the tattle tale body 12 causes the tattle tale indicator 14A to move from a position adjacent the cement head body 1, for example, within the groove 1A in the cement head body 1, to an extended launch indicated position which provides an operator a clear indication that the cement plug 101 has been released/launched. In some exemplary embodiments, a cage handle 111A or biasing assembly 270 may be used in conjunction with the cage to reposition the cage after the cement plug 101 has been launched.
The cement head of the present disclosure allows cement plugs to be launched while cement slurry is flowing and may be used with multiple cement plugs and various sized cement plugs, which may reduce the number of components required to be kept on hand. The disclosed cement head also does not require welded structural components or manifolds, which may increase safety, reliability, and lifespan of the cement head and may lower required inventory and inspection and repair costs.
Although the disclosure describes an exemplary embodiment of the cement head, the disclosure is not intended to limit the present invention to the disclosed embodiments and various modifications are considered to be within the scope of the disclosure. Conditional language, such as, “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain implementations could, but do not necessarily, include certain features and/or elements while other implementations may not. Thus, such conditional language generally is not intended to imply that features and/or elements are in any way required for one or more implementations or that one or more implementations necessarily include these features and/or elements. It is also intended that, unless expressly stated, the features and/or elements presented in certain implementations may be used in combination with other features and/or elements disclosed herein.
The specification and annexed drawings disclose examples embodiments of the present invention. The examples illustrate various features of the disclosure, but those of ordinary skill in the art will recognize that many further combinations and permutations of the disclosed features are possible. Accordingly, various modifications may be made to the disclosure without departing from the scope or spirit thereof. Further, other embodiments may be apparent from the specification and annexed drawings, and practice of disclosed embodiments as presented herein. Examples disclosed in the specification and the annexed drawings should be considered, in all respects, as illustrative and not limiting. Although specific terms are employed herein, they are used in a generic and descriptive sense only, and not intended to the limit the present invention.
Claims
1. A cement head, comprising:
- a cap including an opening that receives a fluid;
- a cement head body connected to the cap;
- a cage located within the cement head body and configured to receive a plug; and
- a plug launch indicator,
- wherein the cage is configured to move between a first position and a second position.
2. The cement head of claim 1, wherein, in the first position of the cage, the fluid follows a first flow path around an outside of the cage and, in the second position of the cage, the fluid follows a second flow path through an inside of the cage.
3. The cement head of claim 1, further comprising a lid located within the cap that diverts the fluid flowing into the cap.
4. The cement head of claim 1, wherein the plug launch indicator includes at least one sealing element at one end of the plug launch indicator and at least one sealing element at an opposite end of the plug launch indicator to pressure balance the plug launch indicator.
5. The cement head of claim 4, wherein the at least one sealing element at the one end of the plug launch indicator and the at least one sealing element at the opposite end of the plug launch indicator are a same size.
6. The cement head of claim 1, further comprising a casing adapter connected to the cement head body and configured to connect the cement head body to a work string.
7. The cement head of claim 1, wherein the cement head body or the cap includes at least one key that locks relative rotation between the cement head body and the cap.
8. The cement head of claim 1, wherein a lifting device is connected to the cage and configured to move the cage from the second position to the first position.
9. The cement head of claim 8, wherein the lifting device includes a biasing assembly that automatically moves the cage from the second position to the first position.
10. The cement head of claim 1, further comprising a downstream cement head body connected to a downstream end of the cement head body, wherein the downstream cement head body includes a downstream cage configured to receive an additional plug and configured to move between a first position of the downstream cage and a second position of the downstream cage.
11. The cement head of claim 10, wherein the downstream cement head body includes a downstream plug launch indicator, the downstream plug launch indicator including at least one sealing element at one end of the downstream plug launch indicator and at least one sealing element at an opposite end of the downstream plug launch indicator to pressure balance the downstream plug launch indicator.
12. The cement head of claim 11, wherein the at least one sealing element at the one end of the downstream plug launch indicator and the at least one sealing element at the opposite end of the downstream plug launch indicator are a same size.
13. The cement head of claim 10, wherein a downstream cage lifting device is connected to the downstream cage and configured to move the downstream cage from the second position of the downstream cage to the first position of the downstream cage.
14. A cement head, comprising:
- a cap including an opening that receives a fluid;
- a cement head body connected to the cap;
- a cage located within the cement head body and configured to receive a plug; and
- a plug launch indicator,
- wherein the plug launch indicator includes at least one sealing element at one end of the plug launch indicator and at least one sealing element at an opposite end of the plug launch indicator to pressure balance the plug launch indicator.
15. The cement head of claim 14, wherein the at least one sealing element at the one end of the plug launch indicator and the at least one sealing element at the opposite end of the plug launch indicator are a same size.
16. The cement head of claim 14, wherein the cage is configured to move between a first position and a second position.
17. The cement head of claim 16, wherein, in the first position of the cage, the fluid follows a first flow path around an outside of the cage and, in the second position of the cage, the fluid follows a second flow path through an inside of the cage.
18. The cement head of claim 16, wherein a lifting device is connected to the cage and configured to move the cage from the second position to the first position.
19. The cement head of claim 18, wherein the lifting device includes a biasing assembly that automatically moves the cage from the second position to the first position.
20. The cement head of claim 14, further comprising a lid located within the cap that diverts the fluid flowing into the cap.
21. The cement head of claim 14, further comprising a casing adapter connected to the cement head body and configured to connect the cement head body to a work string.
22. The cement head of claim 14, wherein the cement head body or the cap includes at least one key that locks relative rotation between the cement head body and the cap.
23. The cement head of claim 14, further comprising a downstream cement head body connected to a downstream end of the cement head body, wherein the downstream cement head body includes a downstream plug launch indicator, the downstream plug launch indicator including at least one sealing element at one end of the downstream plug launch indicator and at least one sealing element at an opposite end of the downstream plug launch indicator to pressure balance the downstream plug launch indicator.
24. The cement head of claim 23, wherein the downstream cement head body includes a downstream cage configured to receive an additional plug and configured to move between a first position of the downstream cage and a second position of the downstream cage.
25. The cement head of claim 24, wherein a downstream cage lifting device is connected to the downstream cage and configured to move the downstream cage from the second position of the downstream cage to the first position of the downstream cage.
26. A method of launching a plug from a cement head, the cement head including, a cap having an opening that receives a fluid, a cement head body connected to the cap, a cage located within the cement head body and configured to receive the plug, and a plug launch indicator, the method comprising:
- positioning the cage in an initial position within the cement head body; loading the plug into an internal bore of the cage; attaching the cap to the cement head body; pumping the fluid through the opening of the cap such that the fluid flows around an outside of the cage; and releasing the cage such that the cage moves from the initial position to a launch position,
- wherein, in the launch position, the fluid is redirected by the cage from flowing around the outside of the cage to flowing through the internal bore of the cage to push the plug out of the cage;
- wherein the fluid flowing through the internal bore of the cage launches the plug from the cage and into the cement head body; and
- wherein the plug moves through the cement head body and contacts the plug launch indicator to actuate the plug launch indicator.
27. The method of claim 26, wherein the plug launch indicator includes at least one sealing element at one end of the plug launch indicator and at least one sealing element at an opposite end of the plug launch indicator to pressure balance the plug launch indicator.
28. The method of claim 26, wherein the cap or the cement head body includes at least one key that locks relative rotation between the cement head body and the cap, and the attaching of the cap to the cement head body includes: aligning the key on one of the cap or the cement head body with a key pocket on another of the cap and the cement head body and inserting the key into the key pocket.
29. The method of claim 26, further comprising operating a lifting device that is connected to the cage to move the cage from the launch position to the initial position.
30. The method of claim 26, further comprising removing the cap to move the cage from the launch position to the initial position.
31. The method of claim 30, wherein a lifting device that includes a biasing assembly automatically moves the cage from the launch position to the initial position when the cap is removed.
32. The method of claim 26, wherein the cement head further includes a downstream cement head body connected to a downstream end of the cement head body, the downstream cement head body including a downstream cage and a downstream plug launch indicator, and
- wherein the downstream cage is configured to receive an additional plug and configured to move between an initial position of the downstream cage and a launch position of the downstream cage.
33. The method of claim 32, the method further comprising
- positioning the downstream cage in the initial position of the downstream cage; loading the additional plug into an internal bore of the downstream cage; attaching the downstream cement head body to the cement head body; pumping the fluid through the opening of the cap such that the fluid flows around an outside of the cage and an outside of the downstream cage; and
- prior to releasing the cage, releasing the downstream cage such that the downstream cage moves from the initial position of the downstream cage to the launch position of the downstream cage to redirect fluid from flowing around the outside of the downstream cage to flowing through the internal bore of the downstream cage to push the additional plug out of the downstream cage,
- wherein the additional plug moves through the downstream cement head body and contacts the downstream plug launch indicator to actuate the downstream plug launch indicator.
Type: Application
Filed: Jun 3, 2019
Publication Date: Dec 3, 2020
Applicant: RIDGELINE OIL TOOLS, LP (ODESSA, TX)
Inventors: GABRIEL ANTONIU SLUP (SPRING, TX), ERIC OWENS HARPER (SPRING, TX), RACE SCOTT RITCHIE (ODESSA, TX), JEFFREY NEAL SCOTT (ODESSA, TX)
Application Number: 16/429,584