An underwater wellhead angle adjustment tool and method of use thereof

Abstract

The application discloses a kind of underwater wellhead angle adjusting tool and its using method, tool includes connecting disc, connecting cylinder, hydraulic cylinder and hydraulic cylinder piston, connecting disc is equipped with connecting cylinder below, connecting disc is connected with high-pressure wellhead running-in tool by bolt, high-pressure wellhead running-in tool is connected with high-pressure wellhead, the outer side of connecting cylinder is equipped with the hydraulic cylinder shell and hydraulic cylinder piston of hydraulic cylinder, hydraulic cylinder piston moves downward and drives the downward locking bushing of high-pressure wellhead to move down, downward locking bushing opens the lock ring of high-pressure wellhead, so that high-pressure wellhead is locked with low-pressure wellhead.The underwater wellhead angle adjusting tool of the application can install adjustable angle high-pressure wellhead vertically on inclined low-pressure wellhead, and controls hydraulic cylinder piston to move downward by hydraulic drive, forces downward locking bushing to open lock ring, so that adjustable angle high-pressure wellhead is locked with low-pressure wellhead; the application is hydraulically driven, and simple to operate; reduce well inclination, facilitate the installation of service tool, blowout preventer and Christmas tree.

Description

Technical Field

[0001] This invention relates to the field of oil and gas drilling and production equipment technology, and in particular to a subsea wellhead angle adjustment tool and its usage method. Background Technology

[0002] Subsea wellheads are key equipment for deepwater oil and gas exploration and development, and generally consist of components such as low-pressure wellheads and high-pressure wellheads. Low-pressure and high-pressure wellheads are usually installed using specialized service tools.

[0003] High-pressure wellhead installation tools are generally divided into two types: high-pressure wellhead insertion tools and high-pressure wellhead rigid locking tools. High-pressure wellhead insertion tools are used to install high-pressure wellheads, connecting and disconnecting from them via a rotating mandrel. High-pressure wellhead rigid locking tools are service tools fitted onto the outside of the high-pressure wellhead insertion tools. They use hydraulic pressure or drill pipe lifting and lowering to tighten the rigid locking device between the high-pressure and low-pressure wellheads, increasing the connection strength and improving the wellhead's fatigue life.

[0004] If the subsea wellhead tilts during installation, and the tilt exceeds 1 degree, it will significantly affect the installation of service tools, blowout preventers, and wellheads, increasing operational risks. Summary of the Invention

[0005] The purpose of this application is to provide a subsea wellhead angle adjustment tool and its usage method to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this application provides the following technical solution:

[0007] A submersible wellhead angle adjustment tool includes a connecting disc, a connecting cylinder, a hydraulic cylinder, and a hydraulic cylinder piston. The connecting cylinder is located below the connecting disc. The connecting disc is bolted to a high-pressure wellhead insertion tool, which is connected to the high-pressure wellhead. The high-pressure wellhead is located inside a low-pressure wellhead. The bottom of the high-pressure wellhead contacts and transmits load to the low-pressure wellhead through a first wellhead spherical joint. An upper support ring is located in the middle of the high-pressure wellhead, and an adjusting ring is fitted above the upper support ring. The upper support ring and the adjusting ring contact and transmit load through a second wellhead spherical joint. The first and second wellhead spherical joints are located on the same... On a spherical surface, a locking ring is fitted on the outer side of the adjusting ring. The low-pressure wellhead has a locking ring groove corresponding to the locking ring. The downward locking bushing is adapted to extend between the locking ring and the adjusting ring to lock the locking ring and the locking ring groove. A hydraulic cylinder is fitted on the outer side of the connecting cylinder. The bottom of the hydraulic cylinder piston contacts the downward locking bushing through the service tool spherical pair and transmits the load. The center of the service tool spherical pair is the same as the center of the first wellhead spherical pair. The downward movement of the hydraulic cylinder piston drives the downward locking bushing of the high-pressure wellhead to move down. The downward locking bushing opens the locking ring of the high-pressure wellhead, and the locking ring locks with the locking ring groove, thus locking the high-pressure wellhead and the low-pressure wellhead.

[0008] Optionally, the upper end face of the connecting plate is connected to the hydraulic control panel by bolts. A hydraulic female connector and a control line are provided above the hydraulic control panel. The hydraulic female connector is connected to the hydraulic male connector and the control line carried by the underwater robot. The underwater robot pressurizes the control line connected to the hydraulic control panel. The control line is connected to the hydraulic cylinder, thereby controlling the piston of the hydraulic cylinder to move downward or upward.

[0009] Optionally, the lower end face of the connecting cylinder contacts the upper end face of the adjusting ring through a supporting spherical pair, and the center of the supporting spherical pair is the same as the center of the service tool spherical pair.

[0010] Optionally, the upper end face of the connecting plate is connected to the level mounting bracket by bolts, and the level mounting bracket is used to install the level.

[0011] A method for using the underwater wellhead angle adjustment tool as described above includes the following steps:

[0012] The high-pressure wellhead insertion tool is connected to the high-pressure wellhead. The connecting plate is connected to the high-pressure wellhead insertion tool by bolts. The high-pressure wellhead insertion tool and the underwater wellhead angle adjustment tool are placed on the high-pressure wellhead and the low-pressure wellhead. The angle of the high-pressure wellhead is adjusted to the predetermined angle by adjusting the boat and moving the derrick.

[0013] The hydraulic cylinder piston is driven downward by the control lines of the hydraulic control panel, which presses down to lock the bushing. The downward locking bushing opens the locking ring, and the locking ring locks with the low-pressure wellhead.

[0014] In summary, the technical effects and advantages of this invention are as follows: The subsea wellhead angle adjustment tool of this invention is a high-pressure wellhead rigid locking tool. It allows an adjustable-angle high-pressure wellhead to be installed nearly vertically on an inclined low-pressure wellhead. Through hydraulic drive, the piston of the hydraulic cylinder moves downward, forcing the downward locking bushing to open the locking ring, thus locking the adjustable-angle high-pressure wellhead to the low-pressure wellhead. This application features hydraulic drive, making operation simple; it reduces well inclination, facilitating the installation of service tools, blowout preventers, and Christmas trees. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram illustrating the use of the underwater wellhead angle adjustment tool in one embodiment of the present invention.

[0017] The components include: 1. Hydraulic control panel; 2. Level mounting bracket; 3. Connecting plate; 4. Connecting cylinder; 5. Hydraulic cylinder housing; 6. Hydraulic cylinder; E1. High-pressure wellhead insertion tool; E2. Low-pressure wellhead; E3. High-pressure wellhead; E4. Drill pipe; Q1. Service tool spherical pair; Q2. First wellhead spherical pair; Q3. Second wellhead spherical pair; E301. Body; E302. Adjusting ring; E304. Downward locking bushing; E305. Locking ring; E306. Upper support ring; E307. Lower support ring. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0020] This embodiment proposes an underwater wellhead angle adjustment tool, such as... Figure 1 The device includes a connecting disc 3, a connecting cylinder 4, a hydraulic cylinder 6, and a hydraulic cylinder piston. The connecting cylinder 4 is located below the connecting disc 3. The connecting disc 3 is bolted to the high-pressure wellhead insertion tool E1. The high-pressure wellhead insertion tool E1 is connected to the high-pressure wellhead E3. The hydraulic cylinder housing 5 and the hydraulic cylinder piston of the hydraulic cylinder 6 are fitted on the outside of the connecting cylinder 4. The downward movement of the hydraulic cylinder piston drives the downward locking bushing E304 of the high-pressure wellhead E3 to move down. The downward locking bushing E304 opens the locking ring E305 of the high-pressure wellhead E3, so that the high-pressure wellhead E3 is locked with the low-pressure wellhead E2.

[0021] Specifically, the upper end face of the connecting plate 3 is connected to the hydraulic control panel 1 by bolts. A hydraulic female connector and a control line are provided above the hydraulic control panel 1. The hydraulic female connector is connected to the hydraulic male connector and the control line carried by the underwater robot. The underwater robot pressurizes the control line connected to the hydraulic control panel 1. The control line is connected to the hydraulic cylinder 6, thereby controlling the piston of the hydraulic cylinder to move downward or upward.

[0022] Specifically, the bottom of the hydraulic cylinder piston contacts and transmits the load to the downward locking bushing E304 of the high-pressure wellhead E3 via the spherical pair Q1 of the service tool. The upper end of the downward locking bushing E304 is spherical, and the contact surface of the bottom of the hydraulic cylinder piston of the underwater wellhead adjustment tool needs to mate with this spherical surface. The low-pressure wellhead E2 is tilted, and the high-pressure wellhead body E301 needs to be vertical after installation. Other components of the high-pressure wellhead E3 are tilted to connect with the low-pressure wellhead. The underwater wellhead adjustment tool connects to the high-pressure wellhead. The underwater wellhead adjustment tool is vertical, and in order to mate with the tilted adjustment ring E302, it needs to be spherical to ensure that the connecting cylinder 4 and the adjustment ring E302 can contact each other regardless of the tilt of the adjustment ring E302. The lower end face of the connecting cylinder 4 of the underwater wellhead adjustment tool is spherical, which mates with the spherical surface of the adjustment ring E302. The bottom of the piston in hydraulic cylinder 6 contacts the downward locking bushing of the high-pressure wellhead through the spherical pair of the service tool and transmits the load.

[0023] Specifically, the upper end face of the connecting plate 3 is connected to the level mounting bracket 2 by bolts, and the level mounting bracket 2 is used to install the level. The level can indicate the tilt angle of the high-pressure wellhead E3.

[0024] The high-pressure wellhead E3 is located inside the low-pressure wellhead E2. The bottom of the high-pressure wellhead E3 contacts and transmits load to the low-pressure wellhead E2 through the first wellhead spherical joint Q2. In this embodiment, the bottom of the body E301 of the high-pressure wellhead E3 is connected to the lower support ring E307 by threads, and contacts and transmits load to the low-pressure wellhead E2 through the first wellhead spherical joint Q2. The middle part of the body E301 is connected to the upper support ring E306 by threads. An adjusting ring E302 is fitted on the upper support ring E306. The upper support ring E306 and the adjusting ring E302 contact and transmit load through the second wellhead spherical joint Q3. A locking ring E305 is fitted on the outside of the adjusting ring E302. When the downward locking bushing E304 moves downward, the downward locking bushing E304 forces the locking ring E305 to open, and the locking ring E305 locks the low-pressure wellhead E2. The first wellhead spherical joint Q2 and the second wellhead spherical joint Q3 are located on the same spherical surface. In this embodiment, the spherical diameters of the first wellhead spherical pair Q2 and the second wellhead spherical pair Q3 are 775mm; there are no special requirements for the fit tolerance, which is H13 / h13 or H14 / h14. In this embodiment, the first wellhead spherical pair Q2 and the second wellhead spherical pair Q3 must be on the same spherical surface to allow the high-pressure wellhead E3 to rotate around the center of the first wellhead spherical pair Q2 and the second wellhead spherical pair Q3, thereby adjusting the tilt of the high-pressure wellhead E3. Simultaneously, the bottom of the hydraulic cylinder piston of the hydraulic cylinder 6 contacts and transmits the load to the downward locking bushing E304 of the high-pressure wellhead E3 through the service tool spherical pair Q1. The service tool spherical pair Q1 is concentric with the centers of the first wellhead spherical pair Q2 and the second wellhead spherical pair Q3.

[0025] Optionally, for better positioning and support of the subsea wellhead angle adjustment tool, the upper end face of the adjusting ring E302 and the lower end face of the connecting cylinder 4 also contact through a supporting spherical pair. The center of the supporting spherical pair is the same as that of the spherical pair Q1 of the service tool. In the initial state where the downward locking bushing E304 has not moved downward, the supporting spherical pair and the spherical pair Q1 of the service tool are coplanar. At this time, the spherical diameter of the spherical pair Q1 of the service tool is 1000mm. There are no special requirements for the fit tolerance, and the fit tolerance is H13 / h13 or H14 / h14.

[0026] A method for using the underwater wellhead angle adjustment tool as described above includes the following steps:

[0027] The high-pressure wellhead insertion tool E1 is connected to the high-pressure wellhead E3. The connecting plate 3 is connected to the high-pressure wellhead insertion tool E1 by bolts. The high-pressure wellhead insertion tool E1 and the underwater wellhead angle adjustment tool are placed on the high-pressure wellhead E3 and the low-pressure wellhead E2. The angle of the high-pressure wellhead E3 is adjusted to the predetermined angle by adjusting the boat and moving the derrick. Adjusting the angle of the high-pressure wellhead E3 by adjusting the boat and moving the derrick is the prior art.

[0028] The hydraulic cylinder piston of hydraulic cylinder 6 is driven to move downward through the control line of hydraulic control panel 1, pressing down to lock bushing E304. The downward locking bushing E304 opens the locking ring E305, and the locking ring E305 locks with the low-pressure wellhead E2.

[0029] Specifically, during the installation of the high-pressure wellhead E3, the drill pipe connects the high-pressure wellhead insertion tool E1, the subsea wellhead angle adjustment tool, and the high-pressure wellhead E3. The high-pressure wellhead E3 is then placed into the low-pressure wellhead E2. The subsea wellhead angle adjustment tool is first pressurized to 200 psi. The hydraulic cylinder of the subsea wellhead angle adjustment tool presses down, locking the bushing E304 downwards a certain distance. At this time, the locking ring E305 is only partially open. The outer wall of the locking ring E305 has a toothed locking part, and the inner wall of the low-pressure wellhead E2 has a corresponding locking ring groove. A small portion of the locking ring E305 is embedded in the locking ring groove on the inner wall of the low-pressure wellhead E2. Since the high-pressure wellhead E3 can contact the low-pressure wellhead E2 through the first wellhead spherical joint Q2 and the second wellhead spherical joint Q3, the angle of the high-pressure wellhead E3 can be adjusted by adjusting the boat and moving the derrick, allowing for vertical adjustment. The distance is adjusted by 1-3mm, but it is impossible to pull the high-pressure wellhead E3 out of the low-pressure wellhead E2 by lifting the drill pipe. Due to the setting of the service tool spherical pair Q1, the subsea wellhead adjustment tool will not interfere with the downward locking bushing E304. Next, the drill pipe is lifted by about 20 klbs to straighten the drill pipe and the high-pressure wellhead. The reading of the level on the subsea wellhead adjustment tool is observed to drop to within 0.5 degrees. The subsea wellhead adjustment tool is then pressurized to 500-1000 psi. The hydraulic cylinder of the subsea wellhead adjustment tool presses down the downward locking bushing E304 to fully open the locking ring E305. The locking force generated by the locking ring E305 is about several hundred klbs. It generates friction on the second wellhead spherical pair Q3 to inhibit the high-pressure wellhead E3 from rotating along the second wellhead spherical pair Q3, so that the high-pressure wellhead E3 cannot move relative to the low-pressure wellhead E2. At this point, the reading on the level instrument on the underwater wellhead adjustment tool is the final tilt angle of the high-pressure wellhead E3.

[0030] In summary, the subsea wellhead angle adjustment tool of this embodiment is a rigid locking tool for a high-pressure wellhead E3. It can install the adjustable-angle high-pressure wellhead E3 almost vertically on the inclined low-pressure wellhead E2, and through hydraulic drive, control the piston of the hydraulic cylinder to move downward, forcing the downward locking bushing E304 to open the locking ring E305, so that the adjustable-angle high-pressure wellhead E3 and the low-pressure wellhead E2 are locked together. This application is hydraulically driven, simple to operate, reduces well inclination, and facilitates the installation of service tools, blowout preventers and wellheads.

[0031] For ease of explanation, spatial relative terms such as "upper," "lower," "outer," and "inner" are used in the embodiments to describe the relationship of one element or feature relative to another element or feature shown in the figures. It should be understood that, in addition to the orientations shown in the figures, spatial terms are intended to include different orientations of the device during use or operation. Therefore, the exemplary term "lower" can encompass both upper and lower orientations.

[0032] Moreover, relational terms such as “3” and “4” are merely used to distinguish one component from another that has the same name, without necessarily requiring or implying any such actual relationship or order between the components.

[0033] Although preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not limiting. Those skilled in the art can make many specific modifications under the guidance of the present invention without departing from the spirit of the invention and the scope of protection of the claims, and these modifications all fall within the scope of protection of the present invention.

Claims

1. An underwater wellhead angle adjustment tool, characterized by, The application relates to a high-pressure wellhead locking device, which comprises a connecting disc, a connecting cylinder, a hydraulic cylinder and a hydraulic cylinder piston, the lower part of the connecting disc is provided with the connecting cylinder, the connecting disc is connected with a high-pressure wellhead running tool through bolts, the high-pressure wellhead running tool is connected with a high-pressure wellhead, the high-pressure wellhead is located in a low-pressure wellhead, the bottom of the high-pressure wellhead is in contact with the low-pressure wellhead through a first wellhead spherical pair and transmits load, the middle part of the high-pressure wellhead is provided with an upper supporting ring, the upper supporting ring is sleeved with an adjusting ring above, the upper supporting ring is in contact with the adjusting ring through a second wellhead spherical pair and transmits load, the first wellhead spherical pair and the second wellhead spherical pair are located on the same spherical surface, the adjusting ring is sleeved with a lock ring outside, the low-pressure wellhead is provided with a lock ring groove corresponding to the lock ring, and a downward locking bushing is adapted to extend into the lock ring and the adjusting ring to lock the lock ring and the lock ring groove; the outer side of the connecting cylinder is sleeved with the hydraulic cylinder, the bottom of the hydraulic cylinder piston is in contact with the downward locking bushing through a service tool spherical pair and transmits load, the ball center of the service tool spherical pair is the same as that of the first wellhead spherical pair, the downward movement of the hydraulic cylinder piston drives the downward movement of the downward locking bushing of the high-pressure wellhead, the lock ring of the high-pressure wellhead is opened by the downward locking bushing, the lock ring is locked with the lock ring groove, and the high-pressure wellhead is locked with the low-pressure wellhead; the lower end surface of the connecting cylinder is in contact with the upper end surface of the adjusting ring through a supporting spherical pair, and the ball center of the supporting spherical pair is the same as that of the service tool spherical pair.

2. The underwater wellhead angle tool of claim 1, wherein, The upper end surface of the connecting disc is connected with a hydraulic control panel through bolts, the upper part of the hydraulic control panel is provided with a hydraulic female joint and a control pipeline, the hydraulic female joint is connected with a hydraulic male joint and a control pipeline carried by an underwater robot respectively, the underwater robot presses into the control pipeline connected with the hydraulic control panel, and the control pipeline is connected with the hydraulic cylinder, so that the downward or upward movement of the hydraulic cylinder piston is controlled.

3. The underwater wellhead angle tool of claim 1, wherein, The upper end surface of the connecting disc is connected with a level mounting frame through bolts, and the level mounting frame is used for mounting a level.

4. A method of using the underwater wellhead angle adjustment tool according to any one of claims 1-3, characterized in that, The application further relates to a high-pressure wellhead locking method, which comprises the following steps: The high-pressure wellhead running tool is connected with the high-pressure wellhead, the connecting disc is connected with the high-pressure wellhead running tool through bolts, the high-pressure wellhead running tool and an underwater wellhead angle adjusting tool are used to place the high-pressure wellhead in the low-pressure wellhead, the angle of the high-pressure wellhead is adjusted to a predetermined angle through the mode of adjusting a ship and moving a derrick; The hydraulic cylinder piston of the hydraulic cylinder is driven to move downward through the control pipeline of the hydraulic control panel, the downward locking bushing is pressed downward, the lock ring is opened by the downward locking bushing, and the lock ring is locked with the low-pressure wellhead.

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