A pipe hydrate unblocking device based on electromagnetic induction

Abstract

This invention relates to a pipeline hydrate unblocking device based on electromagnetic induction, comprising: a mobile control structure disposed in the middle of the pipeline to be unblocked and hydraulically fixed to the pipeline; and at least two electromagnetic unblocking structures, movably disposed at both ends of the pipeline and connected to the mobile control structure via steel wire ropes. The mobile control structure, via the steel wire ropes, drives the electromagnetic unblocking structures to move from both ends towards the middle of the pipeline, thereby unblocking the hydrate blockage from both ends towards the middle. This invention has advantages such as fast unblocking speed, low energy consumption, energy saving and environmental protection, high degree of automation, and safety and reliability. This invention can be applied to hydrate unblocking in long-distance horizontal pipelines on both seabed and land.

Description

Technical Field

[0001] This invention relates to the field of pipeline unblocking technology, and in particular to a pipeline hydrate unblocking device based on electromagnetic induction. Background Technology

[0002] Hydrates are non-stoichiometric, cage-like crystalline substances that resemble ice, formed under high pressure and low temperature conditions by gas and water molecules. Subsea pipelines transporting water-containing media are prone to hydrate formation due to the high pressure and low temperature environment inside; orifice plates, valves, and other pipe fittings on the pipeline also frequently form hydrates due to localized low temperatures caused by the Joule-Thomson effect. The formed hydrates accumulate and clog pipelines, severely impacting oil and gas production, causing huge economic losses, and threatening personnel safety. Safe and rapid hydrate removal from pipelines is of great significance for the efficient development of offshore oil and gas fields, ensuring pipeline flow safety, safeguarding national energy security, and achieving carbon peaking and carbon neutrality.

[0003] Common methods for unblocking pipeline hydrates include: (1) Pressure reduction method, which unblocks the hydrates by reducing the system pressure below the equilibrium pressure of the hydrate phase. However, controlling the pressure reduction rate requires the operator's experience, and the unblocking process requires production to be suspended, which is time-consuming and uneconomical. (2) Chemical agent method, which changes the activity of the solution by adding chemical agents, so that the hydrates under the current conditions enter the safe zone and decompose. However, the amount of chemical agents used is large, which is uneconomical, has poor fluidity (such as ethylene glycol), and is toxic (such as methanol). (3) Heating method, which unblocks the hydrates by heating the blockage to above the equilibrium temperature of the hydrate phase. This includes sleeve bundle heating, electric heating tape heating, direct electric heating and microwave heating. However, the heating method is not suitable for long-distance pipelines and has disadvantages such as immature technology, high energy consumption, uneconomical, and accelerated pipeline corrosion.

[0004] Existing literature provides a mechanical device that uses a motor-driven conical steel to rotate and crush hydrate blockage blocks. This device requires gravity to be delivered to the hydrate blockage in the wellbore to function, making it unsuitable for unblocking horizontal long-distance pipelines. Other literature describes a hydrate unblocking method utilizing the combined action of acid-base neutralization exothermics and a pressure-reducing valve; however, this method is also only applicable to vertical wellbores and cannot be used for horizontal long-distance pipelines. A hydrate blockage detection and unblocking device described in the literature moves along with the pipeline flow by adjusting its own density to match the density of the transported fluid and uses electric heating for unblocking; however, this device cannot be used on already blocked pipelines. Summary of the Invention

[0005] To address the aforementioned problems, the purpose of this invention is to provide a pipe hydrate unblocking device based on electromagnetic induction, which has advantages such as fast unblocking speed, low energy consumption, energy saving and environmental protection, high degree of automation, and safety and reliability.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a pipe hydrate unblocking device based on electromagnetic induction, comprising:

[0007] The mobile control structure is located in the middle of the pipe to be unblocked and is fixed to the pipe by hydraulic means.

[0008] At least two electromagnetic unblocking structures are configured, each movably installed at both ends of the pipe to be unblocked, and connected to the moving control structure via steel wire ropes. The moving control structure drives the electromagnetic unblocking structures to move from both ends to the middle on the pipe to be unblocked via the steel wire ropes, thereby unblocking the hydrate blockage from both ends to the middle.

[0009] Furthermore, the motion control structure includes:

[0010] A retaining ring assembly is located on the outer side of the middle part of the pipe to be unblocked, and is coaxial with the pipe to be unblocked;

[0011] Rubber bladders are disposed inside the retaining ring assembly, located between the retaining ring assembly and the outer wall of the pipe to be unblocked, and at least two bladders are provided to fix the retaining ring assembly to the pipe to be unblocked;

[0012] The spools are symmetrically arranged on both sides of the fixed retainer assembly and are respectively connected to the middle of the wire rope. They are used to rotate and wind the wire rope around the spools to pull the electromagnetic unblocking structure to move towards the middle.

[0013] An electric drive motor, the output end of which is connected to the spool disc, is used to drive the spool disc to rotate; and the electric drive motor is also connected to the rubber bladder, and hydraulic oil is injected into the rubber bladder through an external hydraulic source device to make it expand, so as to fix the retaining ring assembly on the pipe to be unblocked.

[0014] Furthermore, the fixing ring assembly includes a semi-circular clamp, a connecting shaft, and a hydraulic cylinder; the two semi-circular clamps are connected through the connecting shaft and the hydraulic cylinder.

[0015] Furthermore, the electromagnetic unblocking structure includes:

[0016] An electromagnetic unblocking retainer assembly is disposed at the end of the pipe to be unblocked and is coaxial with the pipe to be unblocked;

[0017] At least two springs are provided, symmetrically arranged on both sides inside the electromagnetic unblocking ring assembly, with the first end of each spring connected to the inner wall of the electromagnetic unblocking ring assembly.

[0018] At least two electromagnetic coil discs are provided, symmetrically arranged on both sides inside the electromagnetic unblocking ring assembly. The outer middle part of the electromagnetic coil disc is connected to the second end of the spring, and the spring applies pressure to the electromagnetic coil disc.

[0019] Guide pulleys are located at both ends of the inner side of the electromagnetic coil disc. The spring presses the guide pulleys against the outer wall of the pipe to be unblocked, thereby driving the electromagnetic unblocking structure to move on the pipe to be unblocked.

[0020] Furthermore, the electromagnetic unblocking structure also includes a controller;

[0021] At least two controllers are configured, symmetrically arranged on both sides of the outside of the electromagnetic unblocking ring assembly, and corresponding to the electromagnetic coil disk. The controllers are electrically connected to the electromagnetic coil disk. The electromagnetic coil disk generates a high-frequency magnetic field to form eddy currents in the pipe to be unblocked. The Joule effect of the eddy currents causes the steel pipe body to heat up rapidly. At the same time, under the skin effect, the current density on the inner wall surface of the pipe to be unblocked is high and the temperature is also higher, which promotes the decomposition of the hydrate blockage and its disconnection from the inner wall of the pipe to be unblocked, thus achieving unblocking.

[0022] Furthermore, the controller is equipped with a voltage resonant conversion module and a current regulation module, which can convert DC power into high-frequency AC power of 20-40KHz and control the current magnitude.

[0023] Furthermore, the electromagnetic unblocking structure also includes a power supply compartment; the power supply compartment is disposed on both sides of the outside of the electromagnetic unblocking ring assembly, located between the controller and the outer wall of the electromagnetic unblocking ring assembly; and the power supply compartment is connected to the controller and the electromagnetic coil disk respectively.

[0024] Furthermore, the power supply compartment is fixedly connected to the end of the steel wire rope, and the electromagnetic unblocking structure is moved towards the center by the steel wire rope.

[0025] Furthermore, the electromagnetic unblocking retaining ring assembly includes a semi-circular retaining ring, a connecting pin, and a telescopic cylinder; the two semi-circular retaining rings are connected by the connecting pin and the telescopic cylinder.

[0026] The present invention has the following advantages due to the adoption of the above technical solutions:

[0027] 1. This invention uses a high-frequency magnetic field generated by a coil to induce eddy currents in a steel metal pipe within the magnetic field. The thermal effect of the eddy currents is used to unblock the blockage. This invention has the advantages of fast unblocking speed, low energy consumption, energy saving and environmental protection, high degree of automation, and safety and reliability.

[0028] 2. Compared with the pressure reduction method and the chemical agent method, the present invention has the advantages of short unblocking time, high efficiency and strong environmental friendliness.

[0029] 3. Compared with sheath bundles, electric heating tapes, and direct electric heating methods, the present invention has the advantages of fast heating speed, low energy consumption, safety, environmental protection and energy saving.

[0030] 4. This invention has a high degree of automation and is easy to operate, which can save a lot of manpower for operation and maintenance management.

[0031] In summary, this invention is applicable to the unblocking of hydrates in submarine and land-based horizontal long-distance pipelines. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the overall structure of a pipe hydrate unblocking device based on electromagnetic induction in one embodiment of the present invention;

[0033] Figure 2 This is a diagram of the retaining ring assembly in a non-working state according to an embodiment of the present invention;

[0034] Figure 3 This is a working state diagram of the fixing ring assembly in one embodiment of the present invention;

[0035] Figure 4 This is a schematic diagram of the electromagnetic unblocking retainer assembly structure in one embodiment of the present invention;

[0036] Figure 5 This is a schematic diagram of the control circuit of the electromagnetic unblocking ring assembly in one embodiment of the present invention;

[0037] Figure label:

[0038] 1. Fixed retaining ring assembly; 2. Electromagnetic unblocking retaining ring assembly; 3. Steel wire rope; 11. Semi-circular clamp; 12. Connecting shaft; 13. Hydraulic cylinder; 14. Rubber bladder; 15. Borehole; 16. Electric drive motor; 21. Semi-circular retaining ring; 22. Connecting pin; 23. Telescopic cylinder; 24. Electromagnetic coil disc; 25. Spring; 26. Power supply compartment; 27. Controller; 28. Guide pulley. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0040] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0041] To overcome the shortcomings of existing pipeline hydrate unblocking technologies, such as long processing time, high energy consumption, uneconomical operation, environmental unfriendliness, and difficulty in contacting the blockage, this invention proposes a pipeline hydrate unblocking device based on electromagnetic induction. The device includes a fixed retaining ring assembly and an electromagnetic unblocking retaining ring assembly. The fixed retaining ring assembly is located in the middle of the section to be unblocked on the outside of the pipeline, while two electromagnetic unblocking retaining ring assemblies are symmetrically distributed on both sides of the fixed retaining ring assembly and connected by a steel wire rope. The device uses a high-frequency magnetic field generated by a coil to induce eddy currents within the steel pipe, using the thermal effect of these eddy currents to unblock the hydrate blockage. This invention cleverly uses the pipeline itself as a heat source, innovatively applying electromagnetic induction and the Joule effect of eddy currents to pipeline hydrate unblocking. It has advantages such as rapid heating, low energy consumption, short unblocking time, strong environmental friendliness, and high degree of automation, and is applicable to hydrate unblocking of long-distance horizontal pipelines on both seabed and land.

[0042] In one embodiment of the present invention, a pipe hydrate unblocking device based on electromagnetic induction is provided. In this embodiment, as... Figure 1 As shown, the device includes:

[0043] The mobile control structure is located in the middle of the pipe to be unblocked and is fixed to the pipe by hydraulic means.

[0044] At least two electromagnetic unblocking structures are configured, each movably installed at both ends of the pipe to be unblocked. They are connected to the moving control structure via steel wire rope 3. The moving control structure drives the electromagnetic unblocking structure to move from both ends to the middle of the pipe via the steel wire rope 3, thereby unblocking the hydrate blockage from both ends to the middle.

[0045] The section of pipe to be unblocked is a pre-determined blocked section, and the length of the pipe to be unblocked is determined based on the location of the hydrate blockage block in the pipe and the length of the blockage.

[0046] In the above embodiments, such as Figures 1 to 3 As shown, the movement control structure includes:

[0047] The fixed retaining ring assembly 1 is located on the outer side of the middle part of the pipe to be unblocked, and is coaxial with the pipe to be unblocked. It serves as the main body of the movement control structure and is used to support other components in the movement control structure.

[0048] Rubber bladder 14 is disposed inside the retaining ring assembly 1, between the retaining ring assembly 1 and the outer wall of the pipe to be unblocked, and at least two are provided to fix the retaining ring assembly 1 to the pipe to be unblocked;

[0049] The spool discs 15 are symmetrically arranged on both sides of the fixed retaining ring assembly 1 and are respectively connected to the middle of a steel wire rope 3. They are used to rotate and wind the steel wire rope 3 onto the spool discs 15 to pull the electromagnetic unblocking structure to move towards the middle.

[0050] An electric drive motor 16, whose output end is connected to the spool 15, is used to drive the spool 15 to rotate; the electric drive motor 16 is also connected to the rubber bladder 14, and hydraulic oil is injected into the rubber bladder 14 through an external hydraulic source device to make it expand, so as to fix the retaining ring assembly 1 on the pipe to be unblocked.

[0051] The fixing ring assembly 1 includes a semi-circular clamp 11, a connecting shaft 12, and a hydraulic cylinder 13. The two semi-circular clamps 11 are connected by the connecting shaft 12 and the hydraulic cylinder 13, effectively ensuring the reliability and strength of the connection. Two rubber bladders 14 are respectively disposed on the inner sides of the two semi-circular clamps 11, arranged symmetrically.

[0052] In the above embodiments, such as Figure 1 , Figure 4 As shown, each electromagnetic unblocking structure includes:

[0053] The electromagnetic unblocking ring assembly 2 is located at the end of the pipe to be unblocked, coaxial with the pipe to be unblocked, and serves as the main body of the electromagnetic unblocking structure, supporting other components in the electromagnetic unblocking structure.

[0054] At least two springs 25 are provided, symmetrically arranged on both sides inside the electromagnetic unblocking ring assembly 2, with the first end of the spring 25 connected to the inner wall of the electromagnetic unblocking ring assembly 2.

[0055] At least two electromagnetic coil discs 24 are provided, symmetrically arranged on both sides inside the electromagnetic unblocking ring assembly 2. The outer middle part of the electromagnetic coil disc (24) is connected to the second end of the spring 25, and the spring 25 applies pressure to the electromagnetic coil disc 24.

[0056] Guide pulleys 28 are set at both ends of the inner side of the electromagnetic coil disk 24. Springs 25 press the guide pulleys 28 against the outer wall of the pipe to be unblocked, so as to drive the entire electromagnetic unblocking structure to move on the pipe to be unblocked.

[0057] At least two controllers 27 are symmetrically arranged on both sides of the outside of the electromagnetic unblocking ring assembly 2 and are correspondingly arranged with the electromagnetic coil disk 24. The controllers are electrically connected to the electromagnetic coil disk 24 and control the electromagnetic coil disk 24 to generate a high-frequency magnetic field, so that eddy currents are formed in the pipe to be unblocked. The Joule effect of the eddy currents causes the steel pipe body to be unblocked to heat up rapidly. At the same time, under the action of the skin effect, the current density on the inner wall surface of the pipe to be unblocked is high and the temperature is also higher, which promotes the decomposition of the hydrate blockage and its separation and adhesion from the inner wall of the pipe to be unblocked, thereby achieving unblocking.

[0058] In the above embodiment, the electromagnetic unblocking structure also includes a power supply compartment 26. The power supply compartment 26 is disposed on both sides of the exterior of the electromagnetic unblocking ring assembly 2, located between the controller 27 and the outer wall of the electromagnetic unblocking ring assembly 2; and the power supply compartment 26 is connected to both the controller 27 and the electromagnetic coil disk 24 for power supply. Furthermore, the exterior of the power supply compartment 26 is fixedly connected to the end of the wire rope 3, thereby allowing the wire rope 3 to pull the electromagnetic unblocking structure towards the center.

[0059] In the above embodiment, the electromagnetic unblocking retaining ring assembly 2 includes a semi-circular retaining ring 21, a connecting pin 22, and a telescopic cylinder 23. The two semi-circular retaining rings 21 are connected by the connecting pin 22 and the telescopic cylinder 23, effectively ensuring the reliability and strength of the connection. Two electromagnetic coil discs 24 are respectively disposed on the inner sides of the two semi-circular retaining rings 21, arranged symmetrically.

[0060] In the above embodiments, such as Figure 5 As shown, the controller 27 is equipped with a voltage resonant conversion module and a current regulation module, which can convert DC power into high-frequency AC power of 20-40KHz and control the current magnitude.

[0061] In summary, when in use, the working process of this invention includes the following steps:

[0062] 1) Determine the location and length of the hydrate blockage in the pipeline. Place the fixing ring assembly 1 in the middle of the blocked section. Extend the hydraulic cylinder 13 to cause the two semi-circular clamps 11 to rotate in opposite directions around the connecting shaft 12, forming a closed ring. Then, the electric drive motor 16 injects hydraulic oil into the rubber bladder 14 to expand it, thereby fixing the two semi-circular clamps 11 to the pipeline to be unblocked.

[0063] 2) Pull the two electromagnetic unblocking ring assemblies 2 to the two ends of the hydrate blockage section respectively. The telescopic cylinder 23 extends, causing the two semi-circular rings 21 to rotate in opposite directions around the connecting pin 22, forming a closed ring. At the same time, the electromagnetic coil disk 24 and the guide pulley 28 are pressed against the outer wall of the pipe and support the electromagnetic unblocking ring assembly 2 under the action of the spring 25.

[0064] 3) Turn on the controller 27 and adjust the current to make the electromagnetic coil 24 work. At this time, the adjusted high-frequency current passing through the coil will generate a high-frequency magnetic field. Eddy currents are induced inside the steel pipe in this magnetic field. The Joule effect of the eddy currents causes the steel pipe body to heat up rapidly. At the same time, under the action of the skin effect, the current density on the inner wall surface of the pipe is high and the temperature is also higher, which promotes the decomposition of the hydrate blockage and its separation and adhesion to the inner wall of the pipe.

[0065] 4) At the same time, the electric drive motor 16 drives the spool disk 15 to rotate, and pulls the electromagnetic unblocking ring assembly 2 towards the fixed ring assembly 1 through the steel wire rope 3, thereby realizing the unblocking of the hydrate blockage block from both ends to the middle.

[0066] This invention ingeniously uses the pipe itself as a heat source, applying electromagnetic induction and the Joule effect of eddy currents to unblock pipe hydrates. Compared to pressure reduction methods, chemical methods, and other heating methods, this invention has advantages such as rapid heating, low energy consumption, short unblocking time, and strong environmental friendliness. Furthermore, this invention is highly automated and easy to operate.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pipeline hydrate unblocking device based on electromagnetic induction, used for unblocking hydrates in submarine and land-based horizontal long-distance pipelines, characterized in that, include: The mobile control structure is located in the middle of the pipe to be unblocked and is fixed to the pipe by hydraulic means. At least two electromagnetic unblocking structures are provided, which are movably installed at both ends of the pipe to be unblocked and connected to the moving control structure via a steel wire rope (3). The moving control structure drives the electromagnetic unblocking structure to move from both ends to the middle on the pipe to be unblocked via the steel wire rope (3) to unblock the hydrate blockage block from both ends to the middle. The movement control structure includes: A fixed retaining ring assembly (1) is disposed on the outer side of the middle part of the pipe to be unblocked and is coaxial with the pipe to be unblocked; Rubber bladders (14) are disposed inside the fixed circlip assembly (1) and between the fixed circlip assembly (1) and the outer wall of the pipe to be unblocked. At least two bladders are provided to fix the fixed circlip assembly (1) to the pipe to be unblocked. The spool disc (15) is symmetrically arranged on both sides of the fixed retaining ring assembly (1) and is connected to the middle of a steel wire rope (3) respectively. It is used to rotate the steel wire rope (3) around the spool disc (15) to pull the electromagnetic unblocking structure to move towards the middle. An electric drive motor (16) is connected to the output end of the spool disc (15) to drive the spool disc (15) to rotate; and the electric drive motor (16) is also connected to the rubber bladder (14), and hydraulic oil is injected into the rubber bladder (14) through an external hydraulic source device to make it expand, so as to fix the fixing ring assembly (1) on the pipe to be unblocked; The fixed retaining ring assembly (1) includes a semi-circular clamp (11), a connecting shaft (12), and a hydraulic cylinder (13); the two semi-circular clamps (11) are connected by the connecting shaft (12) and the hydraulic cylinder (13); The electromagnetic unblocking structure includes: An electromagnetic unblocking ring assembly (2) is disposed at the end of the pipe to be unblocked and is coaxial with the pipe to be unblocked; At least two springs (25) are provided and symmetrically arranged on both sides inside the electromagnetic unblocking ring assembly (2). The first end of the spring (25) is connected to the inner wall of the electromagnetic unblocking ring assembly (2). At least two electromagnetic coil discs (24) are provided, symmetrically arranged on both sides inside the electromagnetic unblocking ring assembly (2). The middle of the outer side of the electromagnetic coil disc (24) is connected to the second end of the spring (25), and the spring (25) applies pressure to the electromagnetic coil disc (24). The axis of the electromagnetic coil disc (24) is perpendicular to the axis of the pipe. Guide pulleys (28) are set at both ends of the inner side of the electromagnetic coil disk (24). The spring (25) presses the guide pulleys (28) against the outer wall of the pipe to be unblocked, so as to drive the electromagnetic unblocking structure to move on the pipe to be unblocked.

2. The pipe hydrate unblocking device based on electromagnetic induction as described in claim 1, characterized in that, The electromagnetic unblocking structure also includes a controller (27). At least two controllers (27) are symmetrically arranged on both sides of the outside of the electromagnetic unblocking ring assembly (2) and corresponding to the electromagnetic coil disk (24). The controllers are electrically connected to the electromagnetic coil disk (24). The control electromagnetic coil disk (24) generates a high-frequency magnetic field to form eddy currents in the pipe to be unblocked. The Joule effect of the eddy currents causes the steel pipe body to be unblocked to heat up rapidly. At the same time, under the skin effect, the current density on the inner wall surface of the pipe to be unblocked is high and the temperature is also higher, which promotes the decomposition of the hydrate blockage and its disconnection and adhesion to the inner wall of the pipe to be unblocked, thereby achieving unblocking.

3. The pipeline hydrate unblocking device based on electromagnetic induction as described in claim 2, characterized in that, The controller (27) is equipped with a voltage resonance conversion module and a current regulation module, which can convert DC power into high-frequency AC power of 20-40KHz and control the current magnitude.

4. The pipeline hydrate unblocking device based on electromagnetic induction as described in claim 2, characterized in that, The electromagnetic unblocking structure also includes a power supply compartment (26); the power supply compartment (26) is disposed on both sides of the outside of the electromagnetic unblocking ring assembly (2), located between the controller (27) and the outer wall of the electromagnetic unblocking ring assembly (2); and the power supply compartment (26) is connected to the controller (27) and the electromagnetic coil disk (24) respectively.

5. The pipe hydrate unblocking device based on electromagnetic induction as described in claim 4, characterized in that, The power supply compartment (26) is fixedly connected to the end of the steel wire rope (3) and the electromagnetic unblocking structure is pulled towards the center by the steel wire rope (3).

6. The pipe hydrate unblocking device based on electromagnetic induction as described in claim 1, characterized in that, The electromagnetic unblocking retaining ring assembly (2) includes a semi-circular retaining ring (21), a connecting pin (22), and a telescopic cylinder (23); the two semi-circular retaining rings (21) are connected by the connecting pin (22) and the telescopic cylinder (23).

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