An underwater super-large-caliber wellhead welding site sealing test device

Abstract

The present application relates to a kind of underwater super-large caliber wellhead welding site sealing test device, it is related to marine underwater oil and gas exploration and development equipment technical field, solve the problems of low reliability in prior art, difficult and low function integration degree in centering;Including wellhead cover, the wellhead cover includes connecting cover plate and the sleeve being set at the one end of the connecting cover plate and the gap being inserted in the wellhead, the connecting cover plate is provided with pressurized medium injection hole;Sealing ring, the sealing ring is sleeved on the outer edge surface of the sleeve away from the one end of the connecting cover plate;Fixing part, the fixing part is used to fix the wellhead cover being set on the wellhead;With integrated fast stable installation, sealing, pressure test, high-efficiency disassembly and efficient sealing effect are realized.

Description

Technical Field

[0001] This invention relates to the field of equipment technology for marine underwater oil and gas exploration and development, and more specifically, to a device for testing the sealing performance of underwater ultra-large diameter wellhead welds. Background Technology

[0002] Given the severe imbalance in the exploitation of offshore oil and gas resources in my country, strengthening the development and utilization of these resources can not only alleviate the current energy shortage but also further improve the structure of my country's energy extraction. The development of offshore oil and gas drilling platform technology is a crucial link in the exploitation of offshore energy resources.

[0003] With the deepening development of deep-water oil and gas fields, the size of subsea wellheads is constantly increasing, and the application of ultra-large diameter wellheads is becoming increasingly widespread. Existing ultra-large diameter wellheads consist of a subsea pipeline and a connecting section, with the connecting section welded to the subsea pipeline. Due to the high underwater pressure and the high pressure inside the pipeline during oil and gas transportation, the sealing performance of the welded joints of the fabricated ultra-large wellhead needs to be tested for reliability before being put into production. This is to control and mitigate the risk of pollution to the marine environment. Stable performance and reliable sealing equipment help reduce the difficulty of on-site operations and reduce well control risks.

[0004] In existing technologies, testing devices for such ultra-large diameter wellheads mainly have the following problems: Poor sealing performance: Existing testing tools are prone to sealing failure when dealing with ultra-large diameter and ultra-long wellhead devices and when installation conditions are subject to strict limitations, making it difficult to achieve effective isolation.

[0005] Installation difficulties: Due to its oversized dimensions, traditional testing devices are difficult to align during installation, resulting in low installation efficiency and the risk of jamming.

[0006] Limited functionality: Existing devices cannot simultaneously perform stress testing, functional testing, and rapid disassembly within the same testing process. Summary of the Invention

[0007] The purpose of this invention is to provide a sealing test device for underwater ultra-large diameter wellhead weld positions, so as to solve the problems of low reliability of sealing verification, difficulty in alignment and low functional integration in the prior art.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows: This invention provides a device for testing the sealing performance of underwater ultra-large diameter wellhead welds, comprising: A wellhead cover, the wellhead cover including a connecting cover plate and a sleeve disposed at one end of the connecting cover plate and intermittently inserted into the wellhead, the connecting cover plate being provided with a pressurized medium injection hole; A sealing ring is fitted onto the outer edge surface of the sleeve at the end away from the connecting cover plate; A fastener is used to secure the wellhead cover that is placed on the wellhead.

[0009] Furthermore, the fastener includes: An inner ring plate is disposed opposite to the connecting cover plate. The inner ring plate includes two arc-shaped retaining plates, the inner walls of which are engaged with the outer wall of the wellhead. An outer ring plate, which is detachably sleeved on the circumferential outer edge surface of the inner ring plate; A fixing screw is provided, which slides through the connecting cover plate and the outer ring plate, and locking nuts are threaded to both ends of the fixing screw.

[0010] Furthermore, the inner ring plate has an abutment surface I on its outer circumferential edge, and the outer ring plate has an abutment surface II on its inner hole wall that mates with the abutment surface I.

[0011] Furthermore, the position where the outer wall of the wellhead meets the inner ring plate is set as a conical surface, and the inner hole of the inner ring plate is set as a conical hole at the end away from the abutment surface I, which is adapted to the conical surface of the outer wall of the wellhead.

[0012] Furthermore, it also includes a centralizing ring, which is sleeved on the casing and the wellhead cap is in the state of covering the wellhead, with the centralizing ring locked at the top of the wellhead.

[0013] Furthermore, it also includes at least one retraction screw, one end of which is rotatably connected to the upper end face of the wellhead. The connecting cover plate is provided with a through hole for the retraction screw to pass through, and the inner wall of the through hole is provided with an internal thread that is threadedly connected to the retraction screw.

[0014] Furthermore, a guide screw is provided between two adjacent fixed screws. The guide screw slides through the connecting cover plate and the outer ring plate. Locking nuts are also provided at both ends of the guide screw. The length of the guide screw is greater than the length of the fixed screw.

[0015] Furthermore, at least two lifting grooves are provided on the circumferential outer edge surfaces of the connecting cover plate, the inner ring plate, and the outer ring plate.

[0016] Furthermore, an annular groove is provided on the outer wall of the sleeve for embedding the sealing ring portion of the structure.

[0017] Furthermore, the inner diameter of the outer ring plate is larger than the maximum outer diameter of the wellhead.

[0018] Due to the application of the above-mentioned technical solution, the present invention has the following advantages compared with the prior art: This invention provides an underwater ultra-large diameter wellhead weld sealing test device. By integrating the test device design, it effectively solves the problem that the sealing performance of large diameter interfaces is difficult to verify and prone to failure under deep water pressure. Under the same working conditions, the test device has a more uniform contact stress distribution on the sealing surface and can withstand higher internal and external pressure differences, which significantly improves the sealing reliability during the test process and avoids safety accidents and test interruptions caused by sealing failure. This device integrates rapid and stable installation, sealing, pressure testing, and rapid disassembly, forming a highly integrated testing system. When testing underwater ultra-large diameter wellhead devices, it allows for rapid installation and replacement according to testing requirements, achieving full functional coverage of ultra-large diameter wellhead devices. This integrated design reduces the time-consuming and labor-intensive disassembly and assembly of wellhead testing devices, and the problems of easily damaged seals, achieving efficient disassembly and assembly and efficient sealing effects. It reduces the risk of leakage from the source and improves testing efficiency and the authenticity and accuracy of the data. Attached Figure Description

[0019] The following sections will describe some specific embodiments of the invention in detail by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or portions. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings: Figure 1 This is a cross-sectional view of the overall structure of a preferred embodiment of the present invention; Figure 2 yes Figure 1 Enlarged view of point A in the middle; Figure 3 yes Figure 1 Enlarged view of point B in the middle; Figure 4 This is an axonometric view of the overall structure of a preferred embodiment of the present invention.

[0020] The reference numerals in the attached figures are explained as follows: 1. Horizontal underwater ultra-large diameter wellhead; 11. Underwater pipeline; 12. Connection part; 13. Welding position; 2. Wellhead cap; 21. Connecting cover plate; 22. Casing; 23. Pressurized medium injection hole; 4. Fasteners; 41. Inner ring plate; 411. Arc-shaped clamping plate; 412. Abutment surface I; 413. Conical surface; 42. Outer ring plate; 422. Abutment surface II; 43. Fixing screw; 44. Locking nut; 5. Sealing ring; 6. Straightening ring; 7. Retracting lead screw; 8. Guide screw; 9. Lifting groove. Detailed Implementation

[0021] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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.

[0022] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] 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.

[0024] refer to Figure 1 , Figure 2 and Figure 3 This invention provides a sealing performance testing device for the welded position of an underwater ultra-large diameter wellhead. The underwater ultra-large diameter wellhead includes an underwater pipe 11 and a connecting part 12. The connecting part 12 has a channel communicating with the underwater pipe 11. The connecting part 12 is connected to the underwater pipe 11 by welding. The testing device of this application is mainly used to perform pressure testing on the sealing performance of the welded position 13 of the underwater ultra-large diameter wellhead. During the test, the underwater ultra-large diameter wellhead 1 is placed horizontally, and the testing device is installed at the right end of the wellhead. The left end of the underwater ultra-large diameter wellhead 1 is sealed and plugged by other sealing structures.

[0025] refer to Figure 1 , Figure 2 and Figure 3 The testing device includes a wellhead cover 2, a sealing ring 5, and a fixing component 4. The wellhead cover 2 includes a connecting cover plate 21 and a sleeve 22 disposed at one end of the connecting cover plate 21 and inserted into the channel of the connecting part 12 with a gap. The connecting cover plate 21 and the sleeve 22 are integrally formed. The connecting cover plate 21 is provided with a pressurizing medium injection hole 23. The pressurizing medium injection hole 23 is connected to the pressurizing equipment through a pressurizing pipe. The pressurizing medium in the pressurizing equipment can be hydrogen, compressed air, rust-removed clean water, or oil.

[0026] refer to Figure 1 , Figure 2 and Figure 3Because the inner wall of the connecting part 12 is uneven, in order to improve the sealing between the outer wall of the sleeve 22 and the inner wall of the connecting part 12, two sealing rings 5 ​​are fitted on the outer edge surface of the end of the sleeve 22 away from the connecting cover plate 21. The sealing rings 5 ​​play a sealing role to prevent the pressurized medium from leaking from the inner wall of the connecting part 12 between the sleeve 22 and the connecting part 12. An annular groove is provided on the outer wall of the sleeve 22 to embed the sealing ring 5. The annular groove plays a positioning role for the sealing ring 5, ensuring that the sealing ring 5 is in the set position after installation.

[0027] refer to Figure 1 , Figure 2 and Figure 4 The fixing component 4 is used to fix the wellhead cover 2 installed on the wellhead. The fixing component 4 includes an inner ring plate 41, an outer ring plate 42, and a fixing screw 43. The inner ring plate 41 is arranged at intervals relative to the connecting cover plate 21. The inner ring plate 41 includes two arc-shaped clamping plates 411. The two arc-shaped clamping plates 411 are joined together to form a circular ring plate that is clamped on the outer wall of the connecting part 12. The outer edge of the inner ring plate 41 is provided with an abutment surface I 412. The inner diameter of the outer ring plate 42 is larger than the outer diameter of the connecting part 12, ensuring that the outer ring plate 42 can be fitted onto the connecting part 12 and move to the left. The inner hole wall of the outer ring plate 42 is provided with an abutment surface II 422 that cooperates with the abutment surface I 412. When the outer ring plate 42 is fitted onto the inner ring plate 41... At this time, the contact surface I 412 and the contact surface II 422 cooperate to achieve docking; since the position where the outer wall of the connecting part 12 docks with the inner ring plate 41 is set as a conical surface 413 (that is, the diameter of the outer wall of the wellhead gradually decreases to the left along the horizontal direction), the inner hole of the inner ring plate 41 is set as a conical hole that matches the conical surface 413 of the outer wall of the connecting part 12 (the inner diameter of the conical hole gradually increases to the right along the horizontal direction); the fixing screw 43 passes through the outer ring plate 42 and the connecting cover plate 21 in sequence along its axial direction and is locked and fixed by the locking nut 44. The locking nut 44 is threadedly connected to the fixing screw 43, and the fixing screw 43 is provided with multiple screws evenly distributed along the circumference of the outer ring plate 42 or the connecting cover plate 21.

[0028] refer to Figure 1 , Figure 2 and Figure 4 When fixed by the fastener 4 of this structure, the inner conical hole in the inner ring plate 41 cooperates with the outer conical surface 413 of the connecting part 12, so that the inner ring plate 41 will not move to the right, thereby achieving positioning and fixing. The inner ring plate 41 and the outer ring plate 42 are connected by the mutual cooperation of the abutment surface I 412 and the abutment surface II 422. After being locked by the fixing screw 43, the inner ring plate 41 and the outer ring plate 42 are fastened and fixed. When disassembling, after the fixing screw 43 is removed, the inner ring plate 41 and the outer ring plate 42 are disassembled without any force.

[0029] refer to Figure 1 , Figure 2 and Figure 3 Because the ultra-large diameter well was placed horizontally during the test, and the inner wall of the connecting part 12 was not flat, a straightening ring 6 was also provided to ensure that the casing 22 was coaxial with the wellhead and to ensure the stability and firmness of the connecting cover 21 at the wellhead end. The straightening ring 6 was fitted on the casing 22. When the wellhead cover 2 was in the wellhead state, the straightening ring 6 was locked at the top of the right end of the connecting part 12, which played a positioning and support role and prevented the casing 22 from tilting.

[0030] refer to Figure 1 , Figure 2 and Figure 3 It also includes at least one retraction screw 7, one end of which is rotatably connected to the right end face of the wellhead. The connecting cover plate 21 is provided with a through hole for the retraction screw 7 to pass through. The inner wall of the through hole is provided with an internal thread that is threaded to the retraction screw 7. During installation, after the through hole on the connecting cover plate 21 is aligned with the retraction screw 7, the wellhead cover 2 is moved to the left by turning the retraction screw 7 until it is placed on the wellhead. The principle is the same when retracting, only the turning direction is reversed. This structure facilitates the installation of the wellhead cover 2 and its removal from the wellhead. The operation is simple, convenient, and labor-saving.

[0031] refer to Figure 1 , Figure 2 and Figure 3 A guide screw 8 is provided between two adjacent fixed screws 43. The guide screw 8 slides through the connecting cover plate 21 and the outer ring plate 42. Locking nuts 44 are also provided at both ends of the guide screw 43. The length of the guide screw 8 is greater than the length of the fixed screw 43. Before fixing the connecting cover plate 21 and the outer ring plate 42, they are connected by the guide screw 8. When adjusting the position of the outer ring plate 42 or the connecting cover plate 21, the guide screw 8 plays a guiding role to ensure that the axes of the connecting cover plate 21 and the outer ring plate 42 are in a straight line, which facilitates the quick docking and installation of the fixed screws 43. During fixing, the fixed screws 43 and the locking nuts 44 on the guide screw 8 are used for fixing and locking.

[0032] refer to Figure 1 , Figure 2 and Figure 3 At least two lifting grooves 9 are provided on the circumferential outer edge surfaces of the connecting cover plate 21, inner ring plate 41 and outer ring plate 42. During installation, the connecting cover plate 21, inner ring plate 41 or outer ring plate 42 need to be lifted by lifting equipment for auxiliary assembly. Therefore, the lifting grooves 9 facilitate cooperation with external lifting devices.

[0033] refer to Figures 1-4 Specific working principle: First, using a lifting device, the outer ring plate 42 is fitted onto the wellhead from the right side and moved to point a on the left side of the wellhead. Then, using the lifting device, the wellhead cover 2 is lifted to the right end of the wellhead. The return screw 7 is connected to the threaded through hole on the wellhead cover, and the wellhead cover 2 is screwed on to move towards the end of the wellhead until the connecting cover plate 21 is placed on the end of the wellhead and the casing 22 is inserted into the wellhead. When installing the wellhead cover 2, the sealing ring 5 and the straightening ring 6 are both fitted onto the casing 22. When the wellhead cover 2 is completely placed on the wellhead end, the straightening ring 6 is locked at the end of the wellhead to achieve an effective straightening effect, and the sealing ring 5 is in the set position to achieve an effective sealing effect. Subsequently, the outer ring plate 42 and the connecting cover plate 21 are initially connected by the guide screw 8 to ensure that the outer ring plate 42 can move closer to the connecting cover plate 21. Then, the two arc-shaped clamping plates 411 are clamped on the right side of the wellhead a position and moved to the right until the two arc-shaped clamping plates 411 are clamped at the outer edge conical surface of the connecting part 12. Under the cooperation of the conical surface, the inner ring plate 41 will not move to the right, thus achieving initial positioning. The outer ring plate 42 then moves to the right and fits onto the inner ring plate 41. After the outer ring plate 42 and the inner ring plate 41 are connected, the lock on the guide screw 8 is used to... Tighten nut 44 for pre-locking, and finally fix the connecting cover plate 21 and outer ring plate 42 again by fixing screw 43, thereby fixing this test device on the wellhead. Connect the pressurizing equipment to the pressurizing medium injection hole 23 on the connecting cover plate through the pressurizing pipe, start the pressurizing equipment, and deliver pressurizing medium (such as hydrogen, compressed air, rust-removed clean water or oil) into the wellhead. Gradually increase the pressure to the predetermined test pressure and maintain it for a certain period of time. Observe the pressure change and whether there is any leakage at the wellhead weld, thereby testing the maximum pressure resistance of the wellhead weld 13. After the test is completed, first release the internal pressure, then remove the locking nuts 44 on the fixing screw 43 and guide screw 8 in sequence, and remove the fixing screw 42 and guide screw 8. Slide the outer ring plate 42 off the inner ring plate 41 to the left and remove it. At this time, the inner ring plate 41 and the outer ring plate 42 are not under force, so the two arc-shaped clamping plates 411 can be separated from the outer wall of the wellhead and removed. Finally, turn the back screw 9 in the opposite direction to move the wellhead cover 2 away from the wellhead and smoothly remove the wellhead cover 2 from the wellhead. Then move the outer ring plate 42 to the right to remove it from the wellhead, thus completing the entire test process.

[0034] In summary, the present invention has the following advantages: 1. Addressing the sealing and pressure-bearing challenges posed by "ultra-large diameter wellhead devices" This invention addresses the characteristics of ultra-large diameter underwater wellhead devices by integrating the testing device design. This effectively solves the problem of difficult verification and easy failure of sealing performance of large-diameter interfaces under deep water pressure. Compared with existing small-diameter standard flange connection wellhead testing technology, this testing device has a more uniform stress distribution on the sealing surface under the same working conditions, can withstand higher internal and external pressure differences, significantly improves the sealing reliability during the testing process, and avoids safety accidents and test interruptions caused by sealing failure. 2. Functional integration for "dedicated testing" This device integrates rapid and stable installation, sealing, pressure testing, and rapid disassembly into a highly integrated testing system. When testing underwater ultra-large diameter wellhead devices, it allows for rapid installation and replacement according to testing requirements, achieving full functional coverage of ultra-large diameter wellhead devices. This integrated design reduces the time-consuming and labor-intensive disassembly and assembly of wellhead testing devices, and the problems of easily damaged seals, achieving efficient disassembly and assembly and efficient sealing effects. It reduces the risk of leakage from the source and improves testing efficiency and the authenticity and accuracy of the data. 3. Regarding lifespan and maintenance The locking rod structure enables quick, efficient, and safe assembly and disassembly, as well as replacement of vulnerable parts. This device significantly improves production efficiency and safety during use. Key components are designed to be detachable, eliminating the need for complete lifting and recovery during on-site maintenance; only the core module needs to be replaced, reducing the difficulty of later maintenance and the overall lifecycle cost.

[0035] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A device for testing the sealing performance of underwater ultra-large diameter wellhead welds, characterized in that, include: Wellhead cover (2), the wellhead cover (2) includes a connecting cover plate (21) and a casing (22) disposed at one end of the connecting cover plate (21) and inserted into the wellhead with a gap. The connecting cover plate (21) is provided with a pressurized medium injection hole (23). A sealing ring (5) is fitted onto the outer edge of the sleeve (22) at the end away from the connecting cover plate (21); Fixing member (4), the fixing member (4) is used to fix the wellhead cover (2) covering the wellhead.

2. The underwater ultra-large diameter wellhead weld sealing test device according to claim 1, characterized in that, The fastener (4) includes: Inner ring plate (41), the inner ring plate (41) is disposed opposite to the connecting cover plate (21), the inner ring plate (41) includes two arc-shaped clamping plates (411), the inner wall of the arc-shaped clamping plates (411) is clamped on the outer wall of the wellhead; Outer ring plate (42), which is detachably sleeved on the circumferential outer edge surface of the inner ring plate (41); A fixing screw (43) is slidably passed through the connecting cover plate (21) and the outer ring plate (42). Locking nuts (44) are threaded to both ends of the fixing screw (43).

3. The underwater ultra-large diameter wellhead weld sealing test device according to claim 2, characterized in that, The inner ring plate (41) has an abutment surface I (412) on its circumferential outer edge, and the outer ring plate (42) has an abutment surface II (422) on its inner hole wall that cooperates with the abutment surface I (412).

4. The underwater ultra-large diameter wellhead weld sealing test device according to claim 2 or 3, characterized in that, The wellhead outer wall and the inner ring plate (41) are connected at a position with a conical surface (413). The inner hole of the inner ring plate (41) is configured as a conical hole that matches the conical surface (413) of the wellhead outer wall at the end away from the abutment surface I (412).

5. The underwater ultra-large diameter wellhead weld sealing test device according to claim 1, characterized in that, It also includes a straightening ring (6), which is sleeved on the casing (22), and the wellhead cap (2) is placed on the wellhead. The straightening ring (6) is locked on the top of the wellhead.

6. The underwater ultra-large diameter wellhead weld sealing test device according to claim 1, characterized in that, It also includes at least one retraction screw (7), one end of which is rotatably connected to the upper end face of the wellhead. The connecting cover plate (21) is provided with a through hole through which the retraction screw (7) passes, and the inner wall of the through hole is provided with an internal thread that is threadedly connected to the retraction screw (7).

7. The underwater ultra-large diameter wellhead weld sealing test device according to claim 2, characterized in that, A guide screw (8) is provided between two adjacent fixed screws (43). The guide screw (8) slides through the connecting cover plate (21) and the outer ring plate (42). Locking nuts (44) are also provided at both ends of the guide screw (8). The length of the guide screw (8) is greater than the length of the fixed screw (43).

8. The underwater ultra-large diameter wellhead weld sealing test device according to claim 2, characterized in that, At least two lifting grooves (9) are provided on the circumferential outer edge surfaces of the connecting cover plate (21), the inner ring plate (41) and the outer ring plate (42).

9. The underwater ultra-large diameter wellhead weld sealing test device according to claim 1, characterized in that, The outer wall of the sleeve (22) is provided with an annular groove for embedding part of the sealing ring (5).

10. The underwater ultra-large diameter wellhead weld sealing test device according to claim 1, characterized in that, The inner diameter of the outer ring plate (42) is greater than the maximum outer diameter of the wellhead.

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