A rotary control head device with a ring hydraulic locking type

Abstract

The present invention discloses a rotary control head device with an annular hydraulic locking type, which comprises a blowout preventer pipe, a rotary assembly, a hydraulic system assembly and a housing; the inner diameter of the blowout preventer pipe is larger than the maximum outer diameter of the rotary assembly, and the lower end of the blowout preventer pipe is connected to the top of the housing through a flange; the rotary assembly is arranged in the housing, and the rotary assembly includes a rotary part and a non-rotary part, and the non-rotary part is composed of an upper sealing end cover, an outer cylinder, a lower sealing end cover and an internal bearing; an annular locking claw groove, a sealing ring groove and an annular positioning step are arranged on the outside of the outer cylinder; the hydraulic system assembly includes a hydraulic cylinder, a locking claw and a locking state indicating rod; the rotary assembly realizes the extension or retraction of the locking claw by adopting a plurality of hydraulic cylinders and locking claws which are in the same plane, equidistantly arranged in a circumferential direction and controlled by a remote hydraulic station, so as to facilitate the installation and removal of the rotary assembly, change the traditional installation and connection mode of a hoop type, and simplify the procedure of replacing the rotary control head assembly.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas exploration and development, and in particular to a rotary control head device with a ring-shaped hydraulic locking type. Background Art

[0002] At present, with the continuous demand for safe and efficient drilling and the improvement of environmental protection requirements, especially in the South China Sea, the focus of high-temperature and high-pressure exploration has expanded from the Dongfang area to waters such as Ledong. The temperature is higher, the pressure window is narrower, the operating environment is more severe, and complex situations such as overflow and leakage occur frequently. There is an urgent need to carry out research on the pressure control drilling technology for ultra-high temperature and high pressure with a narrow pressure window.

[0003] The existing hoop-type rotary control head cannot fully meet the requirements of the pressure control drilling technology for offshore platforms. The problems of the existing rotary control head device and system in the application of drilling platforms are mainly manifested in: First, the procedure for replacing the rotary assembly is cumbersome and the wellhead operation time is long; Second, frequent high-altitude operations at the wellhead pose a great safety risk; Third, it cannot efficiently switch the drilling mode, increasing the non-productive operation time; Fourth, when switching the drilling mode, the wellhead mud leaks out, seriously violating environmental protection and safety; Fifth, it cannot meet the full coverage of underbalanced and pressure control drilling and completion operations for jack-up platforms and deepwater platforms in the sea and the requirements for safe and efficient drilling of ultra-high temperature and high pressure wells. Summary of the Invention

[0004] The object of the present invention is to provide a rotary control head device with a ring-shaped hydraulic locking type in view of the above problems existing in the existing rotary control head. The rotary control head device of the present invention will provide technical support for establishing a set of safe and efficient underbalanced and pressure control drilling technology for offshore drilling platforms.

[0005] The rotary control head device with a ring-shaped hydraulic locking type provided by the present invention includes a blowout preventer pipe, a rotary assembly, a hydraulic system assembly, and a housing.

[0006] The housing is the fundamental component forming the rotary control head with a ring-shaped hydraulic locking type and is used for connecting and installing other components.

[0007] The inner diameter of the blowout preventer pipe is larger than the maximum outer diameter of the rotary assembly. The upper end of the blowout preventer pipe is provided with a joint connected to the diversion device; the lower end of the blowout preventer pipe is connected to the top of the housing through a flange.

[0008] The rotating assembly is arranged inside the housing. The rotating assembly includes a rotating part and a non-rotating part. The rotating part includes an upper rubber core assembly, a mandrel assembly, and a lower rubber core assembly. The non-rotating part is located between the upper rubber core assembly and the lower rubber core assembly. The non-rotating part consists of an upper sealing end cover, an outer cylinder, a lower sealing end cover, and an internal bearing. The drill pipe passes through the upper rubber core assembly and the lower rubber core assembly of the rotating part, and a drill tool face seal is formed between the upper and lower rubber cores and the drill pipe, and it rotates together with the drill pipe. An annular locking jaw groove, a sealing groove, and an annular positioning step are provided on the outside of the outer cylinder. A support step is arranged inside the housing through a change in the through-hole diameter to match the positioning step on the outside of the outer cylinder. When the rotating assembly is lowered, the positioning step sits on the support step inside the housing to achieve positioning. A static sealing ring is installed in the sealing groove, and a static seal is formed between the non-rotating part and the inside of the housing through the static sealing ring. The rotating part and the non-rotating part are axially supported, positioned, and rotated by two thrust bearings, one on the upper and one on the lower. At the same time, the upper and lower sealing end covers are fixed to the non-rotating outer cylinder, and a rotating seal is formed between the rotating part and the non-rotating part through a rotating sealing ring. The lubrication and cooling of the bearings between the rotating part and the non-rotating part are carried out by injecting grease for bearing lubrication and cooling.

[0009] The hydraulic system assembly includes hydraulic cylinders, locking jaws, a locking state indicating rod, a hydraulic station (pressurizing system and operating system), and two oil pipes. There are several hydraulic cylinders, and all the hydraulic cylinders are arranged equidistantly around the outside of the housing and are located in the same radial plane. Two oil inlets and outlets are provided on each hydraulic cylinder, and the two oil inlets and outlets of all the hydraulic cylinders are connected in parallel to an annular oil pipe, and two pipe joints are provided on the annular oil pipe; the hydraulic station is connected to the two oil pipes, and the other ends of the two oil pipes are respectively connected to the annular oil pipe of the hydraulic cylinders through two joints. A locking jaw hole is opened on the housing wall surface opposite to each hydraulic cylinder, the locking jaw is movably located in the locking jaw hole, and the locking jaw is threadedly connected to the piston rod of the hydraulic cylinder. The hydraulic station stores oil, pressurizes, and operates, and transports the hydraulic oil through the oil pipe to the hydraulic joint of the rotating control head, and then the hydraulic joint distributes it in parallel to each hydraulic cylinder, and the hydraulic station remotely operates the movement of the hydraulic cylinders. Under the action of the hydraulic cylinders, the locking jaws move radially towards the axis and extend out to clamp in the locking jaw grooves of the outer cylinder to fix the rotating assembly in the housing, or the locking jaws retract radially in the opposite direction of the axis to release the rotating assembly, facilitating the installation or removal of the rotating assembly in the housing. The locking state indicating rod is connected to the piston of the hydraulic cylinder, the locking state indicating rod and the piston rod are respectively located on the left and right sides of the piston, and the locking state indicating rod extends or retracts under the drive of the piston to indicate whether the locking jaws are closed or opened in place.

[0010] The bottom flange of the housing is connected to the annular blowout preventer of the drilling crew or the outer cylinder of the riser of the deepwater platform. A studded flange is provided at the top of the housing and is connected to the overflow pipe or the three-stage telescopic pipe of the riser of the deepwater platform through the studded flange. Four return outlets are opened on the same radial plane at the lower part of the housing, which are respectively used to connect a main return pipeline, a standby return pipeline, a grouting pipeline and a standby outlet. The drill pipe, the rotary assembly and the housing form a pressure-bearing closed fluid passage for the mud to return to the wellhead.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0012] It changes the traditional installation and fixation methods of the rotary assembly and the housing, and the overflow preventer assembly and the housing. The rotary assembly of the present invention realizes the extension or retraction of the locking claws through a plurality of hydraulic cylinders and locking claws that are equidistantly arranged on the same plane and controlled by a remote hydraulic station, so as to realize the installation and removal of the rotary assembly, changing the previous hoop-type installation and connection method. The housing is uniquely designed with a studded flange at the top, which is convenient for installing the overflow preventer flange, also changing the previous hoop-type installation and connection method, and avoiding the problem that the housing can only be connected to the rotary assembly or the overflow preventer assembly. The housing of the present invention can be connected to the rotary assembly and the overflow preventer assembly at the same time without interference. Therefore, during on-site construction, the procedure of replacing the rotary control head assembly is reduced, the non-production time is greatly saved, the safety risk of high-altitude operation is reduced, and the environmental protection and safety risk caused by mud leakage formed by frequent disassembly of the overflow preventer are reduced.

[0013] The present invention lubricates and cools the rotary assembly by injecting grease, changing the traditional lubrication and cooling methods of the rotary control head, and configuring a dedicated pump station, lubrication and cooling system, which greatly reduces the occupied space and costs of materials, operation, transportation, maintenance, etc.

[0014] Other advantages, objectives and features of the present invention will be partially reflected by the following description, and partially will also be understood by those skilled in the art through the research and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 、Schematic structural diagram of the rotary control head device of the annular hydraulic locking type.

[0016] Figure 2 、Schematic connection structure diagram of the overflow preventer.

[0017] Figure 3 、Schematic structural diagram of the rotary assembly.

[0018] Figure 4 、Schematic structural diagram of the hydraulic system assembly.

[0019] Figure 5 、Schematic diagram of the state when the locking claws are retracted, where a is the axial sectional view and b is the radial sectional view.

[0020] Figure 6 Schematic diagram of the locking state of the locking claws, where a is the axial sectional view and b is the radial sectional view.

[0021] Figure 7 Schematic diagram of the overall structure of the housing.

[0022] Figure 8 Axial sectional view of the housing.

[0023] Figure 9 Radial sectional view of the locking claw hole of the housing.

[0024] Figure 10 Radial sectional view of the four return outlets of the housing.

[0025] Reference numerals in the figure:

[0026] Overflow prevention pipe 1, rotating assembly 2, hydraulic system assembly 3, housing 4, drill pipe 5, annular blowout preventer 6, joint 11, well team diversion device 12, diversion device outlet 13, upper rubber core assembly 21, mandrel assembly 22, lower rubber core assembly 23, upper sealing end cover 24, outer cylinder 25, lower sealing end cover 26, bearing 27, locking claw groove 28, positioning step 29, sealing ring (groove) 30, hydraulic cylinder 31, locking claw 32, locking state indicating rod 33, hydraulic station 34, two oil pipes 35, annular oil pipe 36, oil pipe joint 37, studded flange 41, support step 42, locking claw hole 43, return outlet 44, flange 45, annular blowout preventer 6. Specific embodiments

[0027] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not intended to limit the present invention.

[0028] As Figures 1-10 shown, the structure of the annular hydraulic locking type rotary control head device provided by the present invention includes an overflow prevention pipe 1, a rotating assembly 2, a hydraulic system assembly 3, and a housing 4.

[0029] The housing 4 is the fundamental component for forming the annular hydraulic locking type rotary control head and is used to connect and install other components.

[0030] The overflow prevention pipe 1 is an essential equipment and fluid channel for returning mud to the wellhead when removing the rotating assembly during conventional drilling, underbalanced drilling and pressure-controlled drilling. The overflow prevention pipe 1 is a steel pipe with an inner diameter larger than the maximum outer diameter of the rotating assembly. To ensure that the overflow prevention pipe does not need to be disassembled when disassembling the rotating assembly, the rotating assembly can be installed or removed through the inner tube of the overflow prevention pipe using a lowering (or removal) tool. The upper end of the overflow prevention pipe 1 is connected to the well team diversion device 12 through a joint 11, and a diversion device outlet 13 is provided on the diversion device. The flange at the lower end of the overflow prevention pipe is connected to the top of the shell 4. A threaded flange 41 is provided at the top of the shell 4, and the lower end of the overflow prevention pipe is connected to the top of the shell through a threaded flange. The top of the shell is designed to be connected to the overflow prevention pipe by bolts through the threaded flange, and the overflow prevention pipe is installed in place at one time. When installing or removing the rotating assembly, it is lowered or removed through the overflow prevention pipe tube, and the overflow prevention pipe does not need to be disassembled.

[0031] The rotating assembly 2 is arranged inside the housing 4. The rotating assembly includes a rotating part and a non-rotating part (see Figure 3 ). The rotating part includes an upper rubber core assembly 21, a core shaft assembly 22 and a lower rubber core assembly 23. The main function of the rotating part is to seal the annular surface of the drill pipe through the upper and lower rubber cores, and rotate with the drill pipe 5. The non-rotating part is located between the upper rubber core assembly and the lower rubber core assembly. The non-rotating part is composed of an upper sealing end cover 24, an outer cylinder 25, a lower sealing end cover 26, and an internal bearing 27. A bearing support positioning step is designed inside the outer cylinder 25. The drill pipe 5 passes through the upper rubber core assembly and the lower rubber core assembly of the rotating part, and the upper and lower rubber cores and the drill pipe form a drill face seal, and rotate with the drill pipe. An annular locking claw groove 28, a sealing ring (groove) 30 and an annular positioning step 29 are arranged on the outside of the outer cylinder 25. A support step 42 is arranged in the shell through the change of the diameter size to match the positioning step 29 on the outside of the outer cylinder. When the rotating assembly is lowered, the positioning step 29 is seated on the support step 42 in the shell to achieve positioning. The rotating part and the non-rotating part are mutually axially supported, positioned and rotated by two upper and lower thrust bearings. The upper sealing end cover 24 and the lower sealing end cover 26 are fixed on the non-rotating outer cylinder 25, and a direct rotary seal between the rotating part and the non-rotating part is formed by the sealing ring. The bearing lubrication and cooling between the rotating part and the non-rotating part are carried out by injecting grease. The outer cylinder 25 is also provided with an annular sealing ring (groove) 30, a grease injection hole, a pressure relief hole and an exhaust hole. The sealing ring 30 is placed in the annular sealing ring groove to seal the gap between the rotating assembly and the housing. The main function of the non-rotating part is to locate the position of the rotating assembly in the housing, fix the rotating assembly in the housing through the annular hydraulic locking claw, and seal the rotating assembly and the housing through three sealing rings.

[0032] The hydraulic system assembly 3 includes a hydraulic cylinder 31, a locking claw 32, a locking state indicator rod 33, a hydraulic station 34 (pressurizing system and operating system) and two oil pipes 35 (see Figure 4)。There are several hydraulic cylinders, and all the hydraulic cylinders are arranged equidistantly around the outer side of the housing on the same radial plane. Two oil inlet and outlet ports are provided on each hydraulic cylinder, and the two oil inlet and outlet ports of all the hydraulic cylinders are connected in parallel to the annular oil pipe 36, and two pipe connectors 37 are provided on the annular oil pipe. The hydraulic station 34 is connected to two oil pipes 35, and the other ends of the two oil pipes 35 are respectively communicated with the annular oil pipe of the hydraulic cylinder through two connectors 37. A locking claw hole 43 is opened on the wall surface of the housing 4 opposite to each hydraulic cylinder. The locking claw is movably located in the locking claw hole, and the locking claw is threadedly connected to the piston rod of the hydraulic cylinder. The hydraulic station provides energy through a pneumatic booster pump. The hydraulic station stores oil, pressurizes, and operates, and transports the hydraulic oil through the oil pipe to the hydraulic joint of the rotary control head, and then the hydraulic joint distributes it in parallel to each hydraulic cylinder, and remotely operates the movement of the hydraulic cylinder at the hydraulic station. Under the action of the hydraulic cylinder, the locking claw moves radially towards the axis and extends out to clamp in the locking claw groove of the outer cylinder to fix the rotary assembly in the housing, or the locking claw retracts radially in the opposite direction of the axis to release the rotary assembly, facilitating the installation or removal of the rotary assembly in the housing. The locking state indicator rod 33 and the hydraulic cylinder piston, and the locking state indicator rod and the piston rod are respectively located on the left and right sides of the piston. The locking state indicator rod extends or retracts under the drive of the piston, indicating whether the locking claw is closed or opened in place, and the position state of the locking claw can be visually inspected. All the hydraulic cylinders are connected in parallel through the annular oil pipe 36 to ensure uniform liquid supply and pressure, and are connected to the hydraulic station outside the housing to control all the hydraulic cylinders to open or close simultaneously. The hydraulic station transmits hydraulic energy to the hydraulic cylinders through two oil pipes. Through the operation of the remote hydraulic station, the locking claw is closed or opened, realizing the replacement of the rotary assembly without disassembling the anti-spill pipe or performing high-altitude operations.

[0033] When placing or removing the rotary assembly, it is necessary to ensure that the locking claw 32 is in the retracted state. At this time, the locking state indicator rod 33 is in the fully extended state (extending outside the housing), and its working state is shown in the appendix Figure 5 a and b (taking 10 locking claws as an example). After the rotary assembly is placed in place, the locking claw 32 extends towards the rotary assembly, surrounding and locking the rotary assembly, and its working state is shown in the appendix Figure 6 a and b (taking 10 locking claws as an example). At this time, the locking state indicator rod 33 retracts into the housing.

[0034] The structure of the housing is as Figures 7-10 shown. A stud flange 41 is provided at the top of the housing, and a support step 42, a locking claw hole 43, four return ports 44, and a flange 45 at the bottom of the housing are arranged in sequence downward; the support step 42 is located on the inner wall surface of the housing and is used to position the rotary assembly.

[0035] The bottom flange 45 of the housing is connected to the annular blowout preventer of the drilling crew or the outer cylinder of the riser of the deepwater platform. The top of the housing is connected to the choke pipe or the three-section telescopic pipe of the riser of the deepwater platform through the studded flange 41. The rotating assembly 2 is installed on the support step 42 inside the housing and is fixed inside the housing by the locking claws 32 of the hydraulic cylinders installed on the same radial plane. The four return outlets 44 are located on the same radial plane of the housing and are equally spaced, and are respectively used to connect a main return pipeline, a spare return pipeline, a grouting pipeline and a spare outlet. The drill pipe, the rotating assembly and the housing form a pressure-bearing closed fluid channel for the mud to return to the wellhead. The housing 4 is integrally forged and then finely machined, and the main designs include the top studded flange 41, the annular equally spaced locking claw holes 43, the support step 42, the four return outlets 44, the lower flange 45, etc. The lower flange 45 is generally connected to the annular blowout preventer 6 of the land drilling platform and the jack-up offshore drilling platform. The drill pipe passes through the rubber core of the rotating assembly to form a seal on the surface of the drill string. The rotating assembly forms a seal with the housing through the sealing ring 30, thus sealing the wellhead annulus. The fluid can only flow out of the housing outlet to a designated place, such as the pressure control choke manifold, etc.

[0036] The processing and design key points of the annular hydraulic locking type rotating control head device of the present invention are as follows:

[0037] (1) Design and machine several planes on the outer side of the housing for installing the hydraulic cylinders of the hydraulic system;

[0038] (2) Design and machine several locking claw holes on the housing perpendicular to the plane for installing the hydraulic cylinders; the number of hydraulic cylinders is the same as the number of locking claw holes;

[0039] (3) All the locking claws and hydraulic cylinders are located on the same radial plane and are equally spaced and fixed on the outer side of the housing through bolts;

[0040] (4) All the hydraulic cylinders are connected in parallel to ensure uniform liquid supply and pressure, and are connected to the tubing joints outside the housing to ensure that all the hydraulic cylinders are opened or closed simultaneously;

[0041] (5) The hydraulic station transmits the hydraulic energy to the hydraulic cylinders through two hydraulic tubing to realize the operation of the hydraulic mechanism remotely;

[0042] (6) The locking claws are threadedly connected to the piston rods of the hydraulic cylinders;

[0043] (7) The pistons of the hydraulic cylinders are all equipped with locking state indicating rods to show whether the locking claws are closed or opened in place.

[0044] The above are only the preferred embodiments of the present invention and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to equivalent embodiments by using the disclosed technical content within the scope of the technical solution of the present invention. However, as long as it does not depart from the technical content of the technical solution of the present invention, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A rotary control head device with a ring-shaped hydraulic locking type, characterized in that, It includes an anti-overflow pipe, a rotating assembly, a hydraulic system assembly, and a housing; The inner diameter of the anti-overflow pipe is larger than the maximum outer diameter of the rotating assembly. A joint for connecting to a diversion device is provided at the upper end of the anti-overflow pipe; the lower end of the anti-overflow pipe is connected to the top of the housing through a flange; The rotating assembly is arranged inside the housing. The rotating assembly includes a rotating part and a non-rotating part. The rotating part includes an upper rubber core assembly, a mandrel assembly, and a lower rubber core assembly. The non-rotating part is located between the upper rubber core assembly and the lower rubber core assembly. The non-rotating part consists of an upper sealing end cover, an outer cylinder, a lower sealing end cover, and an internal bearing; an annular locking claw groove, a sealing groove, and an annular positioning step are provided on the outside of the outer cylinder; a support step is provided inside the housing through a change in the through-diameter size to match the positioning step on the outside of the outer cylinder. When the rotating assembly is lowered, the positioning step sits on the support step inside the housing to achieve positioning; The hydraulic system assembly includes a hydraulic cylinder, a locking claw, and a locking state indicating rod; there are several hydraulic cylinders, and all the hydraulic cylinders are arranged equidistantly around the outside of the housing and are located in the same radial plane. A ring-shaped hydraulic passage is formed by parallel connection of double pipes between all the hydraulic cylinders. A locking claw hole is opened on the housing wall surface opposite to each hydraulic cylinder. The locking claw is movably located in the locking claw hole, and the locking claw is threadedly connected to the piston rod of the hydraulic cylinder; under the action of the hydraulic cylinder, the locking claw moves radially towards the axis and extends out to clamp in the locking claw groove of the outer cylinder to fix the rotating assembly in the housing, or the locking claw retracts radially in the opposite direction of the axis to release the rotating assembly, facilitating the installation or removal of the rotating assembly in the housing; the locking state indicating rod is connected to the piston of the hydraulic cylinder. The locking state indicating rod and the piston rod are located on the left and right sides of the piston respectively. The locking state indicating rod extends or retracts under the drive of the piston to indicate whether the locking claw is closed or opened in place.

2. The rotary control head device with an annular hydraulic locking type according to claim 1, characterized in that, The hydraulic system assembly also includes a hydraulic station and two oil pipes connected to the hydraulic station; two oil inlets and outlets are provided on each hydraulic cylinder. The two oil inlets and outlets of all the hydraulic cylinders are connected in parallel to the annular oil pipe, and two oil pipe joints are provided on the annular oil pipe; the hydraulic station is connected to the two oil pipes, and the other ends of the two oil pipes are respectively connected to the annular oil pipe of the hydraulic cylinder through two joints.

3. The rotary control head device with a ring-shaped hydraulic locking type as described in claim 2, characterized in that, Several equally spaced and separate flat plates are arranged around the outside of the housing, and the hydraulic cylinders are installed on the flat plates.

4. The rotary control head device with an annular hydraulic locking type as described in claim 1, characterized in that, The top of the housing is bolted to the bottom flange of the anti-overflow pipe through a studded flange.

5. The rotary control head device with an annular hydraulic locking type according to claim 4, characterized in that, The bottom of the housing is connected to the annular blowout preventer of the well team or the outer cylinder of the deepwater platform riser through a flange.

6. The rotary control head device with a ring hydraulic locking type as described in claim 1, characterized in that, The rotating part and the non-rotating part are axially supported, positioned, and rotated by two thrust bearings, one above and the other below.

7. The rotary control head device with a ring hydraulic locking type according to claim 6, characterized in that, A rotating seal is formed between the rotating part and the non-rotating part through a rotating seal ring.

8. The rotary control head device with an annular hydraulic locking type according to claim 1, characterized in that, A static seal is formed between the non-rotating part of the rotating assembly and the inside of the housing through a static seal ring.

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