Hydraulic blowout preventer choke device and method

Abstract

The application discloses a hydraulic blowout-preventing flow resistance device and method, which comprises a sealing pipe and a sealing element installed in the sealing pipe, wherein a first cable passing hole is arranged in the center of the sealing element; further comprising a suspension pipe, a suspension head and a piston; the suspension head is suspended in the suspension pipe, and the lower end of the suspension head is connected with the upper end of the sealing pipe; the piston is installed in a piston channel arranged in the inside of the suspension head, and the piston and the suspension head form an axial sliding sealing pair; a second cable passing hole is arranged in the center of the piston, and the first cable passing hole and the second cable passing hole are concentric; the lower end of the piston extends into the sealing pipe and abuts against the sealing element. The application prevents overflow at the wellhead, does not need to be equipped with overflow collecting devices and vehicles, and reduces the testing and deployment cost of the injection well.

Description

Technical Field

[0001] This invention relates to the field of well testing technology for oilfield water injection wells, specifically a hydraulic blowout preventer and flow control device and method. Background Technology

[0002] During the water injection trial and development process in oilfields, frequent testing and adjustments are required for the injection wells. During these tests, testing instruments are lowered into the well using cables to test the adjusted section. Because the wellhead pressure is greater than zero, blowouts and overflows are possible; therefore, a blowout preventer (BOP) must be installed at the wellhead. The cable connecting the testing instruments must pass through the center of the BOP. Since the cable surface is armored and not smooth, a seal cannot be guaranteed between the BOP and the cable, resulting in well fluid leakage, known as overflow. This overflowing well fluid pollutes the environment.

[0003] To prevent wellhead overflow from damaging the environment, blowout preventer risers and hydraulic blowout preventers are installed on the water injection wellhead equipment (patent available: Wellhead Device for High-Pressure Water Injection Well Blowout Seal Testing, Application No.: 201821253909.8). The main function of the blowout preventer riser is to raise the wellhead to increase the static pressure of the fluid column inside the wellbore. The blowout preventer riser can only slightly reduce overflow, not eliminate it. The hydraulic blowout preventer is located at the upper end of the riser, with the cable passing through it. The hydraulic blowout preventer has a sealing packing gland inside its cavity, and a hydraulic oil input connector is connected to the upper circumference of the hydraulic blowout preventer. The hydraulic blowout preventer uses the pressure of hydraulic oil to press the packing gland tightly, further improving the seal between the hydraulic oil and the cable. However, significant overflow still occurs during field applications. One reason is that the armored cable used in the test has an uneven surface with gaps and poor high-pressure sealing performance, causing injected water to overflow along the blowout preventer during the raising and lowering of the testing instrument. Another reason is that during the cable raising and lowering process, the cable directly rubs against the packing, causing wear on the sealing packing, increasing the central aperture, and losing its sealing effect on the cable, resulting in overflow at the injection wellhead. To prevent injected water from overflowing along the hydraulic blowout preventer and causing environmental pollution, a guide pipe is currently installed on the hydraulic blowout preventer plug to divert the overflow and prevent it from flowing to the wellhead area and polluting the environment. This method requires placing a collection tank with a capacity of several cubic meters at the wellhead and also requires vehicles to transport and move the collection tank. Therefore, this method significantly increases the testing and deployment costs of the injection well.

[0004] Publication (Announcement) No.: CN2878659Y, Publication (Announcement) Date: 2007-03-14 This invention relates to an environmentally friendly blowout preventer (BOP) for oil well testing, including a dynamic seal overflow control assembly and a housing. The dynamic seal overflow control assembly employs a two-stage dynamic seal overflow control assembly, and the housing uses a composite multi-functional housing assembly. A hydraulic control BOP assembly is added, installed inside the housing assembly. The two-stage dynamic seal overflow control assembly is installed at the center of the housing assembly, with the upper end of the housing assembly having an inner sealing surface, and the lower end connected to a flow-blocking pipe assembly. The two-stage dynamic seal control structure using conical hole rubber blocks provides two-stage overflow control for the well fluid, effectively controlling the overflow discharge without affecting cable tripping operations, reducing well fluid overflow pollution to the environment, and allowing operators to directly control the sealing status of the BOP system from the surface. However, the structure is overly complex and the cost is too high.

[0005] Publication (Announcement) No.: CN211924125U, Publication (Announcement) Date: 2020-11-13 This invention relates to the field of blowout preventer (BOP) technology and discloses an oil production testing BOP device, including a BOP pipe and a screw. Foot pedals are fixedly connected to the front and rear sides of the outer surface of the BOP pipe. A fixing plate is fixedly connected to the left side of the outer surface of the BOP pipe. A BOP plug is threadedly connected to the left end of the BOP pipe. A fixing plate is fixedly connected to the right side of the outer surface of the BOP plug. The right end of the screw passes through two sets of fixing plates and is threadedly connected to a nut. This oil production testing BOP device, through the cooperation of the two sets of fixing plates and the screw and nut, makes the connection between the BOP plug and the BOP pipe more stable, and the BOP device safer. The sealing ring is made of rubber, which has extensibility, making the connection between the BOP pipe and the BOP ball pipe tighter and preventing leakage.

[0006] Publication (Announcement) No.: CN2418251Y, Publication (Announcement) Date: 2001-02-07 discloses a high-pressure wellhead testing blowout preventer. It consists of three parts: a hydraulic cable sealing mechanism at the top, a grease injection sealing mechanism in the middle, and a cable anti-overhead mechanism at the bottom. Its key feature is adjustable dual seals and controllable anti-overhead and anti-blowout measures, effectively solving the problem of cable sealing, blowout prevention, and anti-overhead measures during high-pressure well testing.

[0007] In summary, the technical solutions, technical problems to be solved, and beneficial effects of the above-disclosed technologies are all different from those of the present invention. Regarding the more technical features, technical problems to be solved, and beneficial effects of the present invention, the above-disclosed technical documents do not provide any technical inspiration. Summary of the Invention

[0008] In view of the above-mentioned defects in the existing technology, the purpose of the present invention is to provide a hydraulic blowout preventer and method to prevent overflow at the wellhead, without the need for overflow collection devices and vehicles, thus reducing the testing and commissioning costs of water injection wells.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A hydraulic anti-blowout device includes a sealing tube and a sealing element installed inside the sealing tube, wherein a first cable through hole is provided in the center of the sealing element.

[0011] It also includes the suspension tube, suspension head, and piston;

[0012] The suspension head is suspended inside the suspension tube, and the lower end of the suspension head is connected to the upper end of the sealing tube.

[0013] The piston is installed in the piston channel opened inside the suspension head, and the piston and the suspension head form an axial sliding sealing pair.

[0014] A second cable through hole is opened at the center of the piston, and the first cable through hole is concentric with the second cable through hole;

[0015] The lower end of the piston extends into the sealing tube and presses against the seal.

[0016] Furthermore, a pressure-transmitting step is formed on the outer wall of the piston, and a pressure-transmitting hole is formed on the suspension head and the suspension tube, which communicates with the pressure-transmitting step.

[0017] Furthermore, the outer wall of the suspension head and the inner wall of the suspension tube adopt a matching conical sealing axial limiting suspension structure.

[0018] Furthermore, the piston outer wall is fitted with three sealing rings: upper, middle, and lower. The pressure transmission platform is located between the upper and middle sealing rings of the piston, and the lower sealing ring of the piston mates with the inner wall of the sealing tube.

[0019] Furthermore, upper and lower sealing rings are installed on the outer wall of the suspension head, and the pressure transmission hole of the suspension head is located between the upper and lower sealing rings of the suspension head.

[0020] Furthermore, corresponding axial limiting steps are simultaneously provided on the inner wall of the piston channel and the outer wall of the piston of the suspension head.

[0021] Furthermore, a bypass device is also installed on the suspension pipe, which enables the space above the suspension head to connect with the space below the suspension head.

[0022] Furthermore, the bypass device includes a connecting pipe, an upper switching valve, and a lower sealing seat;

[0023] The suspension tube has an upper hole and a lower hole. The upper hole communicates with the space above the suspension head, and the lower hole communicates with the space below the suspension head.

[0024] The lower sealing seat is installed in the lower side hole and seals it. The lower sealing seat has a lower central hole and a lower connecting hole that are connected to each other. The lower central hole is connected to the lower side hole.

[0025] The upper switch valve is installed in the upper side hole and sealed. The upper end of the connecting pipe is connected to the upper connecting hole of the upper switch valve, and the lower end is connected to the lower connecting hole of the lower sealing seat.

[0026] Furthermore, the upper switch valve includes an upper sealing seat, an upper pressure cap, and a valve stem;

[0027] The upper sealing seat has an upper central hole and an upper connecting hole that are connected to each other, and the upper central hole is connected to the upper side hole;

[0028] The valve stem is inserted into the upper center hole to open and close the upper center hole and the upper connecting hole. A valve seal is installed between the valve stem and the upper center hole and is pressed tightly with an upper pressure cap.

[0029] Furthermore, an annular conical groove is formed on the outer wall of the sealing tube, and a radial hole is formed in the suspension tube and an anti-slip screw is installed thereon, with the inner end of the anti-slip screw inserted into the annular conical groove.

[0030] Furthermore, the anti-slip screw includes a left pressure cap, an anti-slip seat, and a pin;

[0031] The anti-top seat is threadedly connected to the radial hole of the suspension pipe, and the connection is kept sealed.

[0032] The pin has an external thread, which connects with the internal thread on the left side of the anti-top seat. The pin passes through the anti-top seat, and the right end of the pin is tapered, fitting into the annular tapered groove. There is a pin sealing ring between the anti-top seat and the pin.

[0033] The internal thread of the left pressure cap is connected to the external thread of the anti-top seat, and the left pressure cap prevents the pin from being dislodged from the anti-top seat.

[0034] Furthermore, the lower end of the sealing tube is connected to a self-sealing installation tube, and the upper end of the self-sealing installation tube abuts against the sealing element inside the sealing tube.

[0035] Furthermore, a self-sealing cylinder is installed inside the self-sealing installation tube, and a catcher is connected to the lower end of the self-sealing cylinder;

[0036] The lower end of the suspension tube is connected to the catcher's matching seat. The self-sealing installation tube and the catcher are both located inside the catcher's matching seat, and the inner wall of the catcher's matching seat is provided with a step for cooperating with the opening and closing of the catcher.

[0037] To achieve the above objectives, the present invention adopts the following technical solution:

[0038] A method for using a hydraulic blowout preventer: The hydraulic blowout preventer is installed on a blowout preventer riser. When the cable is inside the piston, high pressure is injected into the upper surface of the piston's cylindrical platform through the hydraulic injection pipe connection port and hydraulic injection hole. Under the action of the area difference, the piston moves downward, compressing the seal. The inner wall of the seal tightly wraps around the cable, thus achieving a sealing effect. Due to the continuous hydraulic action on the piston, the seal can continue to be maintained even after the cable wears down the seal.

[0039] Compared with the prior art, the present invention has the following advantages:

[0040] This invention is installed on a blowout preventer riser. When the cable is inside the piston, high pressure is applied to the upper surface of the piston's cylindrical platform. Due to the area difference, the piston moves downward, compressing the seal. The inner wall of the seal tightly wraps around the cable, achieving a sealing effect. Because the piston is subjected to continuous hydraulic pressure, the seal can continue to be maintained even after the cable wears down the seal. Therefore, this invention achieves its purpose, overcomes the problems of existing technologies, prevents overflow at the wellhead, eliminates the need for overflow collection devices and vehicles, reduces testing and adjustment costs for water injection wells, and prevents overflow water from spraying onto the wellhead, protecting the environment from pollution. It has significant economic and social benefits. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the structure of a hydraulic anti-spray and flow-blocking device according to the present invention;

[0042] Figure 2 A schematic diagram of the structure for preventing the set screw from shifting out;

[0043] Figure 3 This is a schematic diagram of the bypass device.

[0044] In the diagram: 1. Suspension pipe; 2. Suspension head; 3. Upper suspension sealing ring; 4. Lower suspension sealing ring; 5. Piston; 6. Anti-slip screw; 7. Catch holder seat; 8. Upper piston sealing ring; 9. Bypass device; 10. Lower piston sealing ring; 11. Seal; 12. Sealing pipe; 13. Self-sealing installation pipe; 14. Self-sealing cylinder; 15. Catch. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] Example 1:

[0047] Please see Figures 1 to 3The present invention provides a technical solution:

[0048] A hydraulic blowout preventer includes a suspension pipe 1, a suspension head 2, an upper suspension sealing ring 3, a lower suspension sealing ring 4, a piston 5, an anti-slip screw 6, a catcher mounting seat 7, an upper piston sealing ring 8, a bypass device 9, a lower piston sealing ring 10, a seal 11, a sealing pipe 12, a self-sealing mounting pipe 13, a self-sealing cylinder 14, and a catcher 15. The internal shoulder of the catcher mounting seat 7 cooperates with the catcher 15 to release and catch water well testing instruments. The suspension head 2 has a hydraulic injection hole 2-1, which connects to the lower interior of the suspension head 2. The upper suspension sealing ring 3 and the lower suspension sealing ring 4 are installed on the suspension head 2, with the upper suspension sealing ring 3 positioned above the hydraulic injection hole 2-1 and the lower suspension sealing ring 4 positioned below the hydraulic injection hole 2-1. Below the inlet 2-1, the diameter of the upper section 5-1 of the piston 5 is smaller than the diameter of the cylindrical platform 5-2. The piston 5 is installed inside the suspension head 2. The upper section 5-1 matches the upper inner hole of the suspension head 2. There is an upper piston sealing ring 8 between the upper section 5-1 and the upper inner hole of the suspension head 2, sealing the gap between the upper section 5-1 and the upper inner hole of the suspension head 2. There is a lower piston sealing ring 10 between the cylindrical platform 5-2 and the lower inner hole of the suspension head 2, sealing the gap between the cylindrical platform 5-2 and the lower inner hole of the suspension head 2. The upper piston sealing ring 8 is above the hydraulic injection hole 2-1, and the lower piston sealing ring 10 is below the hydraulic injection hole 2-1. (Seal 11) Installed inside the sealing tube 12, the sealing element 11 is made of non-metallic material and can deform under pressure. The upper part of the sealing tube 12 is connected to the lower part of the suspension head 2. After the upper part of the sealing tube 12 is connected to the lower part of the suspension head 2, the lower part of the piston 5 is inserted into the sealing tube 12, and the lower end face of the piston 5 presses against the sealing element 11. The self-sealing cylinder 14 is made of non-metallic material and is installed inside the self-sealing installation tube 13. The upper part of the self-sealing installation tube 13 is connected to the lower part of the sealing tube 12, and the upper end face of the self-sealing installation tube 13 abuts against the lower end face of the sealing element 11. The upper part of the catcher 15 is connected to the lower part of the self-sealing installation tube 13. An annular groove 12-1 is provided on the outer wall of the sealing tube 12. The upper part of the catcher matching seat 7 is connected to the lower part of the suspension tube 1. The catcher matching seat 7 and the suspension head 2 are connected to the lower part of the suspension head 2. The connection of the hanging pipe 1 is kept sealed. The hanging head 2 sits on the inner conical cylindrical surface of the hanging pipe 1, limiting the hanging head 2 within the hanging pipe 1 so that it cannot descend. The upper and lower sealing rings 3 and 4 seal the gap between the hanging head 2 and the hanging pipe 1. The hanging pipe 1 has a hydraulic injection pipe connection port 1-1, which corresponds to the hydraulic injection hole 2-1, allowing hydraulic oil injected by an external hydraulic device to enter the cylindrical platform 5-2. The bypass device 9 is installed on the side of the hanging pipe 1. The upper and lower ends of the bypass device 9 are sealed at the connection with the hanging pipe 1. When the inside of the bypass device 9 is open, the well fluid below the lower sealing ring 4 can be transferred to the upper sealing ring 3 through the bypass device 9.The piston 5, seal 11, self-sealing cylinder 14, and catcher 15 all have cable passage holes inside. The diameter of the cable passage hole in the self-sealing cylinder 14 is larger than the cable diameter.

[0049] The bypass device 9 includes an upper sealing gasket 9-1, an upper left sealing ring 9-2, an upper sealing sleeve 9-3, an upper right sealing ring 9-4, an upper sealing seat 9-5, an upper pressure cap 9-6, an upper insertion sealing ring 9-7, a valve seal 9-8, a valve stem 9-9, a connecting pipe 9-10, a lower insertion sealing ring 9-11, a lower sealing sleeve 9-12, a lower sealing seat 9-13, a lower sealing gasket 9-14, a lower left sealing ring 9-15, and a lower right sealing ring 9-16. The upper sealing seat 9-5 has an upper central hole 9-5-1, and the side of the upper sealing seat 9-5 has an upper connecting hole 9-5-2. The upper central hole 9-5-1 communicates with the upper connecting hole 9-5-2. The upper left sealing ring 9-2 and the upper right sealing ring 9-4 are installed on the upper sealing seat 9-5. Ring 9-2 is located to the left of the upper connecting hole 9-5-2, and upper right sealing ring 9-4 is located to the right of the upper connecting hole 9-5-2. Upper sealing gasket 9-1 and upper sealing sleeve 9-3 are fitted onto upper sealing seat 9-5. Upper left sealing ring 9-2 and upper right sealing ring 9-4 seal the gap between upper sealing sleeve 9-3 and upper sealing seat 9-5. The right end face of upper sealing sleeve 9-3 is limited by the shoulder of upper sealing seat 9-5. The external thread of valve stem 9-9 is connected to the internal thread of upper sealing seat 9-5. The left end cone of valve stem 9-9 is fitted with the internal port of the center hole 9-5-1 for sealing. Valve seal 9-8 is fitted onto valve stem 9-9 and installed into the right hole of upper sealing seat 9-5. Upper pressure cap 9-6 is fitted onto the right side of upper sealing seat 9-5. The upper pressure cap 9-6 presses the valve seal 9-8 to maintain a seal between the valve seal 9-8 and the valve stem 9-9. The left side of the upper sealing seat 9-5 has a thread for connection with the suspension pipe 1. The lower sealing seat 9-13 has a lower center hole 9-13-2 and a lower connecting hole 9-13-1 on its side. The lower center hole 9-13-2 communicates with the lower connecting hole 9-13-1. A lower left sealing ring 9-15 and a lower right sealing ring 9-16 are installed on the lower sealing seat 9-13. The lower left sealing ring 9-15 is located to the left of the lower connecting hole 9-13-1, and the lower right sealing ring 9-16 is located to the right of the lower connecting hole 9-13-1. The lower sealing gasket 9-14 and the lower sealing sleeve 9-12 are fitted onto the lower sealing seat. On seat 9-13, lower left sealing ring 9-5 and lower right sealing ring 9-16 seal the gap between lower sealing sleeve 9-12 and lower sealing seat 9-13. The right end face of lower sealing sleeve 9-12 is limited by the shoulder of lower sealing seat 9-13. The left part of lower sealing seat 9-13 has threads for connection with suspension pipe 1. Connecting pipe 9-10 has a center hole 9-10-1. The upper end of connecting pipe 9-10 is inserted into the lower side of upper sealing sleeve 9-3, and there is an upper insertion sealing ring 9-7 at the insertion point to keep the insertion point of connecting pipe 9-10 and upper sealing sleeve 9-3 sealed. The lower end of connecting pipe 9-10 is inserted into the upper side of lower sealing sleeve 9-12, and there is a lower insertion sealing ring 9-11 at the insertion point to keep the insertion point of connecting pipe 9-10 and lower sealing sleeve 9-12 sealed.The lower connecting hole 9-13-1, the center hole 9-10-1, and the upper connecting hole 9-5-2 are interconnected.

[0050] An anti-slip screw 6 is installed on the suspension pipe 1. The front end of the pin of the anti-slip screw 6 is inserted into the annular groove 12-1 so that the suspension head 2 will not move upward when the lower pressure is higher than the upper pressure.

[0051] The anti-slip screw 6 includes a left pressure cap 6-1, an anti-slip seat 6-2, a pin sealing ring 6-3, and a pin 6-4. The left end of the anti-slip seat 6-2 has a thread for connection with the suspension pipe 1. After the anti-slip seat 6-2 is threadedly connected to the suspension pipe 1, the connection remains sealed. The external thread of the pin 6-4 connects with the internal thread on the left side of the anti-slip seat 6-2. The pin 6-4 passes through the anti-slip seat 6-2, with both ends of the pin 6-4 outside the anti-slip seat 6-2. Between the anti-slip seat 6-2 and the pin 6-4... There is a pin sealing ring 6-3, which seals the gap between the inner wall of the anti-top seat 6-2 and the outer wall of the pin 6-4. The internal thread of the left pressure cap 6-1 is connected to the external thread of the anti-top seat 6-2. The function of the left pressure cap 6-1 is to prevent the pin 6-4 from exiting the anti-top seat 6-2. The right end of the pin 6-4 is conical, and the annular groove 12-1 is also conical. The conical part of the right end of the pin 6-4 cooperates with the annular groove 12-1 to prevent the sealing tube 12 from moving.

[0052] When the suspension head 2 is seated, open the valve stem 9-9 to connect the upper center hole 9-5-1 with the lower center hole 9-13-2, so that the pressure at the lower part of the suspension head 2 is balanced with the pressure at the upper part, and the suspension head 2 is seated in place.

[0053] Example 2:

[0054] Please see Figures 1 to 3 The present invention provides a technical solution:

[0055] Instructions for use of hydraulic anti-blowout device:

[0056] The catcher seat 7 of the hydraulic blowout preventer is installed on the blowout preventer riser. When the cable is inside the piston, high pressure is injected into the upper surface of the piston's cylindrical platform through the hydraulic injection pipe connection port 1-1 and the hydraulic injection hole 2-1. Under the action of the area difference, the piston moves downward, compressing the seal. The inner wall of the seal tightly wraps around the cable, thus achieving a sealing effect. Because the piston is subjected to continuous hydraulic pressure, the seal can continue to be maintained even after the cable wears down the seal. Therefore, this invention can achieve its purpose, overcome the problems existing in the prior art, and prevent overflow from the wellhead.

[0057] All components not discussed in detail in this application, as well as the connection methods of these components, are well-known technologies in this field and will not be elaborated upon further. Examples include welding and threaded connections.

[0058] In this invention, the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0059] In the description of this invention, it should be understood that the terms "upper," "lower," "left," "right," "front," "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or unit 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 this invention.

[0060] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0061] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A hydraulic anti-blowout device, comprising a sealing tube and a sealing element installed inside the sealing tube, wherein a first cable through hole is provided in the center of the sealing element; Its features are, It also includes the suspension tube, suspension head, and piston; The suspension head is suspended inside the suspension tube, and the lower end of the suspension head is connected to the upper end of the sealing tube. The piston is installed in the piston channel opened inside the suspension head, and the piston and the suspension head form an axial sliding sealing pair. A second cable through hole is opened at the center of the piston, and the first cable through hole is concentric with the second cable through hole; The lower end of the piston extends into the sealing tube and presses against the sealing element; The piston outer wall is provided with a pressure-transmitting step, and the suspension head and suspension tube are provided with pressure-transmitting holes that communicate with the pressure-transmitting step. The outer wall of the suspension head and the inner wall of the suspension tube adopt a matching conical sealing axial limiting suspension structure. A bypass device is also installed on the suspension pipe, which enables the space above the suspension head to be connected with the space below the suspension head. The bypass device includes an upper sealing gasket, an upper left sealing ring, an upper sealing sleeve, an upper right sealing ring, an upper sealing seat, an upper pressure cap, an upper insertion sealing ring, a valve seal, a valve stem, a connecting pipe, a lower insertion sealing ring, a lower sealing sleeve, a lower sealing seat, a lower sealing gasket, a lower left sealing ring, and a lower right sealing ring. The upper sealing seat has an upper central hole and an upper connecting hole on its side. The upper central hole communicates with the upper connecting hole. The upper left sealing ring and the upper right sealing ring are installed on the upper sealing seat, with the upper left sealing ring positioned to the left of the upper connecting hole. On the side, the upper right sealing ring is located on the right side of the upper connecting hole. The upper sealing gasket and upper sealing sleeve are fitted onto the upper sealing seat. The upper left and upper right sealing rings seal the gap between the upper sealing sleeve and the upper sealing seat. The right end face of the upper sealing sleeve is limited by the shoulder of the upper sealing seat. The external thread of the valve stem is connected to the internal thread of the upper sealing seat. The left end cone of the valve stem fits and seals with the internal port of the central hole. The valve sealing element is fitted onto the valve stem and installed into the right hole of the upper sealing seat. The upper pressure cap is connected to the right side of the upper sealing seat. The valve seal is tightened to maintain a seal between the valve seal and the valve stem. The upper sealing seat has a thread on the left side for connection to the suspension pipe. The lower sealing seat has a lower center hole and a lower connecting hole on its side. The lower center hole communicates with the lower connecting hole. A lower left sealing ring and a lower right sealing ring are installed on the lower sealing seat. The lower left sealing ring is located to the left of the lower connecting hole, and the lower right sealing ring is located to the right of the lower connecting hole. A lower sealing gasket and a lower sealing sleeve are fitted onto the lower sealing seat. The lower left and lower right sealing rings seal the lower valve stem. The gap between the sealing sleeve and the lower sealing seat, the right end face of the lower sealing sleeve is limited by the shoulder of the lower sealing seat, the left side of the lower sealing seat has a thread for connecting with the suspension pipe, the connecting pipe has a central hole, the upper end of the connecting pipe is inserted into the lower side of the upper sealing sleeve, and there is an upper insertion sealing ring at the insertion point to keep the connecting pipe and the upper sealing sleeve sealed, the lower end of the connecting pipe is inserted into the upper side of the lower sealing sleeve, and there is a lower insertion sealing ring at the insertion point to keep the connecting pipe and the lower sealing sleeve sealed, and the lower connecting hole, the central hole and the upper connecting hole are connected; The outer wall of the sealing tube is provided with an annular conical groove, the suspension tube is provided with a radial hole and an anti-slip screw is installed, and the inner end of the anti-slip screw is inserted into the annular conical groove. The anti-slip screw includes a left pressure cap, an anti-slip seat, and a pin; The anti-top seat is threadedly connected to the radial hole of the suspension pipe, and the connection is kept sealed. The pin has an external thread, which connects with the internal thread on the left side of the anti-top seat. The pin passes through the anti-top seat, and the right end of the pin is tapered, fitting into the annular tapered groove. There is a pin sealing ring between the anti-top seat and the pin. The internal thread of the left pressure cap is connected to the external thread of the anti-top seat, and the left pressure cap prevents the pin from being dislodged from the anti-top seat; The lower end of the sealing tube is connected to the self-sealing installation tube, and the upper end of the self-sealing installation tube abuts against the sealing element inside the sealing tube; A self-sealing cylinder is installed inside the self-sealing installation tube, and a catcher is connected to the lower end of the self-sealing cylinder. The lower end of the suspension tube is connected to the catcher's matching seat. The self-sealing installation tube and the catcher are both located inside the catcher's matching seat, and the inner wall of the catcher's matching seat is provided with a step for cooperating with the opening and closing of the catcher. The piston outer wall is fitted with three sealing rings: upper, middle, and lower. The pressure transmission platform is located between the upper and middle sealing rings of the piston, and the lower sealing ring of the piston mates with the inner wall of the sealing tube. Upper and lower sealing rings are installed on the outer wall of the suspension head, and the pressure transmission hole of the suspension head is located between the upper and lower sealing rings of the suspension head; The piston channel inner wall and piston outer wall of the suspension head are simultaneously provided with corresponding axial limiting steps.

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