Sand control device for wellhead of oil and gas well

Abstract

This disclosure relates to a sand control device for oil and gas wellheads, comprising a connecting cylinder and a guide cylinder located above the connecting cylinder; the lower end of the connecting cylinder is connected to the wellhead, and the upper end of the connecting cylinder is connected to the lower end of the guide cylinder. A settling chamber is coaxially arranged inside the connecting cylinder, forming an annular flow channel between the settling chamber and the inner wall of the connecting cylinder. The upper end of the settling chamber is vertically connected to the lower port of the guide cylinder, and multiple annularly arranged connecting holes are opened on the upper side wall of the settling chamber, through which the annular flow channel is connected to the guide cylinder; the upper end of the guide cylinder is connected to the lower end of the tree, and a plate-shaped filter screen is provided on the upper part of the guide cylinder, and a funnel-shaped filter screen is provided on the lower part of the guide cylinder. The funnel-shaped filter screen, the plate-shaped filter screen, and the settling chamber are coaxially arranged, and an outlet extending to the outside of the connecting cylinder is provided on the side wall of the settling chamber, with a sealing plug fitted at the outlet. This sand control device for oil and gas wellheads can promptly separate sand particles from the oil and gas mixture after sand production, ensuring continuous and stable oil and gas transportation.

Description

Technical Field

[0001] This disclosure relates to the field of oil and gas extraction technology, and more specifically, to a sand control device for oil and gas wellheads. Background Technology

[0002] During the oil and gas extraction process, underground oil and gas reservoirs are mostly loose sandstone reservoirs. These reservoirs have poor rock cementation and low strength. During the entire process of drilling, well completion and oil and gas extraction, the sand particles in the reservoir will continuously fall off and peel off due to multiple factors such as drilling fluid scouring, formation pressure drop, and high-speed oil and gas flow. They will rise along the wellbore to the surface wellhead along with the high-pressure oil and gas.

[0003] During the surface transportation of the oil and gas mixture after sand production, the sand particles in the mixture will cause continuous erosion and wear on the surface equipment such as the wellhead, valves, flow meters, and oil pipelines. Long-term operation will lead to a decrease in the sealing performance of the equipment, a shortened service life, and frequent equipment failures. At the same time, sand particles are prone to deposit and accumulate in the oil and gas flow channels, equipment cavities, and parts such as pipe bends and valve interfaces, causing blockage of the oil and gas flow channels. Utility Model Content

[0004] The purpose of this disclosure is to provide a sand control device for oil and gas wellheads, which can promptly separate sand particles from the oil and gas mixture after sand production, ensuring continuous and stable oil and gas transportation.

[0005] To achieve the above objectives, this disclosure provides a sand control device for oil and gas wellheads, including a connecting cylinder and a guide cylinder located above the connecting cylinder; the lower end of the connecting cylinder is connected to the wellhead, and the upper end of the connecting cylinder is connected to the lower end of the guide cylinder; a settling chamber is coaxially arranged inside the connecting cylinder, and an annular flow channel is formed between the settling chamber and the inner wall of the connecting cylinder; the upper end of the settling chamber is vertically connected to the lower port of the guide cylinder, and a plurality of annularly arranged connecting holes are provided on the upper side wall of the settling chamber. The flow channel is connected to the guide tube through the connecting hole; the upper end of the guide tube is connected to the lower end of the wellhead, and the upper part of the guide tube is provided with a plate-shaped filter screen, and the lower part of the guide tube is provided with a funnel-shaped filter screen. The funnel-shaped filter screen, the plate-shaped filter screen and the settling chamber are arranged coaxially so that the sand particles intercepted by the funnel-shaped filter screen and the plate-shaped filter screen fall into the settling chamber. The side wall of the settling chamber is provided with a discharge port extending to the outside of the connecting tube, and the discharge port is fitted with a sealing plug.

[0006] Optionally, the guide tube is constructed in a conical shape, and the diameter of the guide tube gradually decreases from bottom to top.

[0007] Optionally, there are at least two discharge outlets, and the discharge outlets are evenly arranged around the axis of the settling chamber.

[0008] Optionally, the outlet is constructed as a tubular structure, and the outlet, the settling chamber, and the connecting cylinder are integrally formed.

[0009] Optionally, the bottom of the funnel-shaped filter screen has perforations, the plate-shaped filter screen is constructed as a circular structure, and the outer diameter of the plate-shaped filter screen is not greater than the diameter of the perforations.

[0010] Optionally, there are at least three connecting holes, which are evenly arranged around the lower port of the guide tube.

[0011] Optionally, the funnel-shaped filter screen has a plurality of first filter holes spaced apart on its sidewall, and the plate-shaped filter screen has a plurality of second filter holes spaced apart, wherein the diameter of the second filter holes is smaller than the diameter of the first filter holes.

[0012] Optionally, the funnel-shaped filter screen has an annular mounting part on the outer periphery of its upper end, and a limiting groove is formed on the inner side of the lower end of the guide tube. An annular retaining groove is formed on the side wall of the limiting groove, and a C-shaped retaining ring is engaged in the annular retaining groove. The annular mounting part is clamped and fixed between the bottom wall of the limiting groove and the C-shaped retaining ring.

[0013] Optionally, the lower end of the connecting cylinder is provided with a first flange, the upper end of the connecting cylinder is provided with a second flange, the lower end of the guide cylinder is provided with a third flange that mates with the second flange, and the upper end of the guide cylinder is provided with a fourth flange for connecting with the lower end connection port.

[0014] Through the above technical solution, the oil and gas wellhead sand control device disclosed herein includes a connecting cylinder and a guide cylinder. A settling chamber is provided inside the connecting cylinder, and an annular flow channel is formed between the settling chamber and the inner wall of the connecting cylinder. Multiple connecting holes arranged in a ring are opened on the upper side wall of the settling chamber. The annular flow channel is connected to the guide cylinder through the connecting holes. Plate-shaped filter screens and funnel-shaped filter screens are arranged vertically inside the guide cylinder. During oil and gas transportation, the oil and gas mixture flows from bottom to top, passing sequentially through the annular flow channel and connecting holes before entering the guide cylinder. Inside the guide cylinder, larger-diameter sand particles in the oil and gas mixture are first intercepted by the funnel-shaped filter screen. Smaller sand particles are then intercepted by a plate-shaped filter, ensuring comprehensive interception. Simultaneously, the funnel-shaped filter, plate-shaped filter, and settling chamber are coaxially arranged, allowing the intercepted sand particles to fall smoothly into the settling chamber. This effectively separates the sand particles from the oil and gas mixture, preventing sand particles from entering subsequent surface equipment and ensuring the performance of related surface equipment. It also prevents sand particles from clogging oil and gas flow channels, thus ensuring the continuity and stability of oil and gas extraction. Furthermore, by using a sealing plug at the outlet on the side wall of the settling chamber, accumulated sand particles can be periodically discharged through the outlet, making operation simple, time-saving, and labor-saving.

[0015] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the sand control device at the wellhead of an oil and gas well provided in the embodiments of this disclosure;

[0017] Figure 2 This is another structural schematic diagram of the sand control device at the wellhead of an oil and gas well provided in the embodiments of this disclosure;

[0018] Figure 3 yes Figure 2 A magnified view of a section at point A in the middle;

[0019] Figure 4 yes Figure 2 A magnified view of a section at point B.

[0020] Explanation of reference numerals in the attached drawings: 10. Connecting cylinder; 11. First flange; 12. Second flange; 20. Flow guide cylinder; 21. Limiting groove; 22. Annular groove; 23. C-type retaining ring spring; 24. Third flange; 25. Fourth flange; 30. Settling chamber; 301. Annular flow channel; 302. Connecting hole; 31. Discharge port; 32. Sealing plug; 40. Plate-shaped filter screen; 50. Funnel-shaped filter screen; 51. Perforation; 52. First filter hole; 53. Annular mounting part; 60. Lower end connection port. Detailed Implementation

[0021] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0022] In this disclosure, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the relative positions of the corresponding components in the direction of gravity when they are in use, and "inner" and "outer" refer to their relative positions to the contours of the corresponding components themselves. Furthermore, the terms "first," "second," etc., used in this disclosure are for distinguishing one element from another and do not have sequential or importance implications. In the following description, when referring to the accompanying drawings, unless otherwise explained, the same reference numerals in different drawings denote the same or similar elements. The above definitions are for explanation and illustration only and should not be construed as limiting this disclosure.

[0023] According to exemplary embodiments of this disclosure, reference is made to Figures 1 to 4 As shown, a sand control device for oil and gas wellheads is provided, including a connecting cylinder 10 and a guide cylinder 20 located above the connecting cylinder 10; the lower end of the connecting cylinder 10 is used to communicate with the wellhead, and the upper end of the connecting cylinder 10 is connected to the lower end of the guide cylinder 20. A settling chamber 30 is coaxially arranged inside the connecting cylinder 10, and an annular flow channel 301 is formed between the settling chamber 30 and the inner wall of the connecting cylinder 10. The upper end of the settling chamber 30 is vertically connected to the lower end of the guide cylinder 20, and a plurality of annularly arranged connecting holes 302 are opened on the upper side wall of the settling chamber 30. 301 is connected to the guide tube 20 through the connecting hole 302; the upper end of the guide tube 20 is connected to the lower end connection port 60 of the oil well tree, and the upper part of the guide tube 20 is provided with a plate-shaped filter screen 40, and the lower part of the guide tube 20 is provided with a funnel-shaped filter screen 50. The funnel-shaped filter screen 50, the plate-shaped filter screen 40 and the settling chamber 30 are arranged coaxially so that the sand particles intercepted by the funnel-shaped filter screen 50 and the plate-shaped filter screen 40 fall into the settling chamber 30. The side wall of the settling chamber 30 is provided with a discharge port 31 extending to the outside of the connecting tube 10, and the discharge port 31 is fitted with a sealing plug 32.

[0024] Through the above technical solution, the oil and gas wellhead sand control device disclosed herein includes a connecting cylinder 10 and a guide cylinder 20. The connecting cylinder 10 is provided with a settling chamber 30, and an annular flow channel 301 is formed between the settling chamber 30 and the inner wall of the connecting cylinder 10. Multiple connecting holes 302 arranged in an annular pattern are opened on the upper side wall of the settling chamber 30. The annular flow channel 301 is connected to the guide cylinder 20 through the connecting holes 302. Plate-shaped filter screens 40 and funnel-shaped filter screens 50 are arranged vertically inside the guide cylinder 20. During the oil and gas transportation process, the oil and gas mixture passes through the annular flow channel 301 and the connecting holes 302 from bottom to top and then enters the guide cylinder 20. Inside the guide cylinder 20, the funnel-shaped filter screen 50 first intercepts larger sand particles in the oil and gas mixture, and then the plate-shaped filter screen 40 intercepts smaller sand particles, thus achieving comprehensive interception.

[0025] Because the funnel-shaped filter screen 50, the plate-shaped filter screen 40, and the settling chamber 30 are arranged coaxially, the intercepted sand particles can fall smoothly into the settling chamber 30, achieving effective separation of sand particles from the oil and gas mixture. This prevents sand particles from entering subsequent surface equipment with the oil and gas, ensuring the performance of related surface equipment. It also prevents sand particles from clogging the oil and gas flow channels, thereby ensuring the continuity and stability of oil and gas extraction. In addition, by using a sealing plug 32 with the discharge port 31 on the side wall of the settling chamber 30, the sand particles accumulated in the settling chamber 30 can be periodically discharged through the discharge port 31. The operation is simple, time-saving, and labor-saving.

[0026] In this disclosure, the upper end of the settling chamber 30 is connected and fitted with the lower end of the guide tube 20. Specifically, the inner diameter of the upper end of the settling chamber 30 is equal to the inner diameter of the lower end of the guide tube 20, and the end faces of the two are in contact. Thus, after assembly, the inner wall of the upper end of the settling chamber 30 and the inner wall of the lower end of the guide tube 20 can remain flush, so that oil and gas can smoothly enter the guide tube 20.

[0027] According to exemplary embodiments of this disclosure, such as Figure 1 and Figure 2 As shown, the guide tube 20 can be constructed as a conical structure, and the aperture of the guide tube 20 gradually decreases from bottom to top. That is to say, the lower end of the guide tube 20 has a larger diameter and the upper end has a smaller diameter, forming an inverted conical structure. This allows the oil-gas mixture to gradually converge towards the center of the guide tube 20 during its ascent, thus making more thorough contact with the funnel-shaped filter screen 50 and the plate-shaped filter screen 40 in the central area. This ensures that sand particles can be effectively intercepted by the filter screens, improving the sand control effect.

[0028] According to exemplary embodiments of this disclosure, such as Figure 2As shown, there are at least two discharge outlets 31, and the discharge outlets 31 are evenly arranged around the axis of the settling chamber 30. That is to say, the discharge outlets 31 are evenly distributed in a circle on the side wall of the settling chamber 30. The number of discharge outlets 31 can be set to two, three or four, which can be flexibly set according to actual needs. Multiple discharge outlets 31 can significantly improve the discharge speed of sand particles in the settling chamber 30. Especially when the amount of sand particles accumulated in the settling chamber 30 is large, multiple discharge outlets 31 can realize the rapid discharge of sand particles and avoid local residual accumulation of sand particles in the settling chamber 30.

[0029] According to exemplary embodiments of this disclosure, such as Figure 2 and Figure 3 As shown, the outlet 31 can be constructed as a tubular structure, and the outlet 31, settling chamber 30, and connecting cylinder 10 are integrally formed. The integral forming method ensures the connection strength and sealing between the outlet 31, settling chamber 30, and connecting cylinder 10, while reducing assembly steps.

[0030] According to exemplary embodiments of this disclosure, such as Figure 2 and Figure 4 As shown, the bottom of the funnel-shaped filter screen 50 has a perforation 51, the plate-shaped filter screen 40 is constructed in a circular structure, and the outer diameter of the plate-shaped filter screen 40 is not greater than the aperture of the perforation 51. The perforation 51 allows unintercepted sand particles and oil-gas mixtures that have passed through the funnel-shaped filter 50 to pass smoothly into the area of ​​the plate-shaped filter 40 for secondary interception. The outer diameter of the plate-shaped filter 40 is not greater than the aperture of the perforation 51 at the bottom of the funnel-shaped filter 50. For example, the outer diameter of the plate-shaped filter 40 can be set to 50-55 mm, and the aperture of the perforation 51 can be set to 60-65 mm. For example, the outer diameter of the plate-shaped filter 40 is set to 50 mm, and the aperture of the perforation 51 is set to 60 mm. This allows the perforation 51 to completely cover the plate-shaped filter 40, meaning that the plate-shaped filter 40 is completely aligned with the area above the perforation 51. Consequently, the sand particles intercepted by the plate-shaped filter 40 can pass smoothly through the perforation 51 under gravity and fall into the lower settling chamber 30 for collection.

[0031] According to exemplary embodiments of this disclosure, such as Figure 2 As shown, there are at least three connecting holes 302, which are evenly arranged around the lower port of the guide tube 20. When the oil-gas mixture enters the annular flow channel 301 and enters the guide tube 20 through the connecting holes 302, the impact force of the oil-gas mixture after entering the guide tube 20 through the connecting holes 302 is reduced due to the larger diameter of the lower port of the guide tube 20. At this time, the intercepted sand particles can fall down by their own gravity, while the oil and gas overflow from the upper end of the plate-shaped filter screen 40, thus achieving the separation of sand particles.

[0032] According to exemplary embodiments of this disclosure, such as Figure 2 and Figure 4 As shown, the funnel-shaped filter screen 50 has multiple first filter holes 52 spaced apart on its sidewall, and the plate-shaped filter screen 40 has multiple second filter holes spaced apart. The diameter of the second filter holes is smaller than that of the first filter holes 52. The first filter holes 52 are used to intercept large-diameter sand particles, while the second filter holes are used to intercept small-diameter sand particles and a small amount of large-diameter sand particles that are not intercepted by the funnel-shaped filter screen 50. Thus, the cooperation between the funnel-shaped filter screen 50 and the plate-shaped filter screen 40 achieves graded interception, relatively reducing the amount of sand particles accumulated on both screens, preventing rapid clogging, and extending their service life.

[0033] According to exemplary embodiments of this disclosure, such as Figure 4 As shown, the upper outer periphery of the funnel-shaped filter screen 50 may be provided with an annular mounting part 53, and the lower inner side of the guide tube 20 is provided with a limiting groove 21. An annular slot 22 is provided on the side wall of the limiting groove 21. A C-shaped retaining ring 23 is snapped into the annular slot 22. The annular mounting part 53 is clamped and fixed between the bottom wall of the limiting groove 21 and the C-shaped retaining ring 23. In the above technical solution, the limiting groove 21 is used to accommodate the annular mounting part 53 and to initially position the funnel-shaped filter screen 50. A C-shaped retaining ring spring 23 is snapped into the annular groove 22. The C-shaped retaining ring spring 23 has a certain elasticity and can be snapped into the annular groove 22. The annular mounting part 53 is clamped and fixed between the bottom wall of the limiting groove 21 and the C-shaped retaining ring spring 23. That is, through the support of the bottom wall of the limiting groove 21 and the pressing of the C-shaped retaining ring spring 23, the funnel-shaped filter screen 50 is fixedly installed in the guide tube 20, effectively restricting the axial and radial movement of the funnel-shaped filter screen 50. It is easy to disassemble and assemble, and convenient to maintain or replace the funnel-shaped filter screen 50.

[0034] like Figure 2 As shown, the plate-shaped filter 40 of this disclosure can be installed on the upper part of the guide tube 20 in the same way as the funnel-shaped filter 50. To avoid repetition, this disclosure will not go into detail here.

[0035] According to exemplary embodiments of this disclosure, such as Figure 1 and Figure 2As shown, the lower end of the connecting cylinder 10 may be provided with a first flange 11, the upper end of the connecting cylinder 10 is provided with a second flange 12, the lower end of the guide cylinder 20 is provided with a third flange 24 that mates with the second flange 12, and the upper end of the guide cylinder 20 is provided with a fourth flange 25 for connecting with the lower end connection port 60. The first flange 11 is used for flange connection with the wellhead of the oil and gas well, achieving fixation and sealing between the connecting cylinder 10 and the wellhead; the second flange 12 mates with the third flange 24, achieving flange connection between the connecting cylinder 10 and the guide cylinder 20; the fourth flange 25 is used for flange connection with the lower end connection port 60 of the Christmas tree, achieving precise connection between the sand control device at the wellhead of this oil and gas well and the Christmas tree and wellhead.

[0036] like Figures 1 to 4 As shown, the working process of the oil and gas wellhead sand control device disclosed herein is detailed below:

[0037] First, the first flange 11 of the connecting cylinder 10 is connected to the wellhead, the second flange 12 is connected to the third flange 24 of the guide cylinder 20, the fourth flange 25 of the guide cylinder 20 is connected to the lower end connection port 60 of the production tree, and the outlet 31 is sealed with the sealing plug 32 to complete the installation of the sand control device at the wellhead of this oil and gas well.

[0038] In use, the oil-gas mixture carrying sand particles enters the connecting cylinder 10 through the first flange 11, and then enters the guide cylinder 20 through the annular flow channel 301 and the connecting hole 302 in sequence. Under the guidance of the guide cylinder 20, it converges to the center and first undergoes coarse filtration through the funnel-shaped filter screen 50 to intercept large-diameter sand particles. The intercepted large-diameter sand particles fall directly into the settling chamber 30 under their own gravity. The remaining oil-gas mixture continues to rise and passes through the plate-shaped filter screen 40 to intercept small-diameter sand particles and a small amount of large-diameter sand particles that are not intercepted by the funnel-shaped filter screen 50. The sand particles intercepted by the plate-shaped filter screen 40 fall into the settling chamber 30 through the perforation 51 for sand particle collection.

[0039] The oil and gas mixture filtered by the funnel-shaped filter screen 50 continues to rise and enters the wellhead through the fourth flange 25 to complete the subsequent surface transportation;

[0040] When the amount of sand in the settling chamber 30 is large, close the relevant valves to stop the conveying, open the sealing plug 32, and quickly discharge the sand through multiple evenly arranged discharge ports 31. After the discharge is completed, close the sealing plug 32 and resume normal operation.

[0041] As can be seen from the above, the sand control device at the wellhead of this oil and gas well has a compact overall structure, which can promptly separate sand particles from the oil and gas mixture, prevent sand particles from entering subsequent surface equipment with the oil and gas, ensure the performance of related surface equipment, and at the same time prevent sand particles from blocking the oil and gas flow channel, thereby ensuring the continuity and stability of oil and gas extraction.

[0042] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0043] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0044] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A sand control device for oil and gas wellheads, characterized in that, Includes a connecting cylinder (10) and a guide cylinder (20) located above the connecting cylinder (10); The lower end of the connecting cylinder (10) is used to communicate with the wellhead, and the upper end of the connecting cylinder (10) is connected with the lower end of the guide cylinder (20). A settling chamber (30) is coaxially arranged inside the connecting cylinder (10). An annular flow channel (301) is formed between the settling chamber (30) and the inner wall of the connecting cylinder (10). The upper end of the settling chamber (30) is connected to the lower end of the guide cylinder (20). A plurality of connecting holes (302) arranged in an annular pattern are opened on the upper side wall of the settling chamber (30). The annular flow channel (301) is connected to the guide cylinder (20) through the connecting holes (302). The upper end of the guide tube (20) is connected to the lower end connection port (60) of the oil well tree, and the upper part of the guide tube (20) is provided with a plate-shaped filter screen (40), and the lower part of the guide tube (20) is provided with a funnel-shaped filter screen (50). The funnel-shaped filter screen (50), the plate-shaped filter screen (40) and the settling chamber (30) are arranged coaxially so that the sand particles intercepted by the funnel-shaped filter screen (50) and the plate-shaped filter screen (40) fall into the settling chamber (30). The side wall of the settling chamber (30) is provided with an outlet (31) extending to the outside of the connecting tube (10), and the outlet (31) is fitted with a sealing plug (32).

2. The sand control device for oil and gas wellheads according to claim 1, characterized in that, The guide tube (20) is constructed in a conical shape, and the diameter of the guide tube (20) gradually decreases from bottom to top.

3. The sand control device for oil and gas wellheads according to claim 1, characterized in that, There are at least two outlets (31), and the outlets (31) are evenly arranged around the axis of the settling chamber (30).

4. The sand control device for oil and gas wellheads according to claim 3, characterized in that, The outlet (31) is constructed as a tubular structure, and the outlet (31), the settling chamber (30) and the connecting cylinder (10) are integrally formed.

5. The sand control device for oil and gas wellheads according to claim 2, characterized in that, The bottom of the funnel-shaped filter (50) has a perforation (51), the plate-shaped filter (40) is constructed in a circular structure, and the outer diameter of the plate-shaped filter (40) is not greater than the aperture of the perforation (51).

6. The sand control device for oil and gas wellheads according to claim 1, characterized in that, There are at least three connecting holes (302), which are evenly arranged around the lower port of the guide tube (20).

7. The sand control device for oil and gas wellheads according to claim 1, characterized in that, The funnel-shaped filter screen (50) has a plurality of first filter holes (52) spaced apart on its sidewall, and the plate-shaped filter screen (40) has a plurality of second filter holes spaced apart, wherein the diameter of the second filter holes is smaller than the diameter of the first filter holes (52).

8. The sand control device for oil and gas wellheads according to claim 7, characterized in that, The funnel-shaped filter screen (50) has an annular mounting part (53) on the outer periphery of its upper end. The guide tube (20) has a limiting groove (21) on the inner side of its lower end. The limiting groove (21) has an annular slot (22) on its side wall. A C-shaped retaining ring spring (23) is snapped into the annular slot (22). The annular mounting part (53) is clamped and fixed between the bottom wall of the limiting groove (21) and the C-shaped retaining ring spring (23).

9. The sand control device for oil and gas wellheads according to claim 1, characterized in that, The lower end of the connecting cylinder (10) is provided with a first flange (11), the upper end of the connecting cylinder (10) is provided with a second flange (12), the lower end of the guide cylinder (20) is provided with a third flange (24) that is connected to the second flange (12), and the upper end of the guide cylinder (20) is provided with a fourth flange (25) for connecting to the lower end connection port (60).

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