Blowout preventer with dynamic fluid blowout prevention function and use method thereof

Abstract

The present invention provides a blowout preventer with dynamic fluid blowout prevention function and a use method thereof. The blowout preventer comprises a flow tube, flanges are arranged at both ends of the flow tube, a radial blowout prevention mechanism for buffering sudden pressure changes of the fluid is arranged on the flow tube, and a one-way blowout prevention mechanism for buffering sudden pressure changes of the unidirectionally flowing fluid is arranged on the flow tube. The radial blowout prevention mechanism buffers the pressure change in the radial direction of the fluid, and the one-way blowout prevention mechanism buffers the fluid in a flowing state. The guide tube and the internal piston can buffer the impact force along the direction of the fluid, which solves the problem that the buffer component of the wellhead blowout preventer in the past oil pipeline is not in the same direction as the fluid flow direction, the buffer effect is not reasonable, and the blowout prevention effect is not good. The present invention has a reasonable structure, performs blowout prevention and buffering protection on the dynamic fluid, the buffer structure is in the same direction as the fluid flow direction, the fluid pressure is fully released, and the blowout prevention effect is significant.

Description

Technical Field

[0001] The invention discloses a blowout preventer with dynamic fluid blowout prevention function and a use method thereof, and relates to the technical field of wellhead blowout preventers used in petroleum mining. Background Art

[0002] Blowout preventers are used to close the wellhead during oil testing, well repair, and well completion operations to prevent blowout accidents. They combine the functions of full sealing and semi-sealing into one, and have the characteristics of simple structure, easy operation, and high pressure resistance. They are commonly used safety sealing wellhead devices in oil fields to prevent blowouts.

[0003] During oil drilling, it is installed on the casing head at the wellhead to control the blowout of high-pressure oil, gas, and water. When the oil and gas pressure in the well is very high, the blowout preventer can seal the wellhead (close it tightly). When heavy mud is pressed into the drill pipe, there is a four-way under the gate to replace the mud invaded by gas, increase the pressure of the liquid column in the well, and suppress the spraying of high-pressure oil and gas.

[0004] In the past, blowout preventers used internal pistons or rubber rings for buffering, but this buffering method is only suitable for static fluid buffering. Because in the dynamic oil transmission process, the buffers of blowout preventers on the market are mostly set on the outside of the pipeline, and the activity direction of the buffers on many blowout preventers is directly perpendicular to the fluid flow direction. This causes the dynamic fluid flow direction and the buffer to be not in the same straight line, which will cause the buffering effect to not be fully exerted and the blowout prevention effect is poor. Therefore, there is an urgent need for a blowout preventer with dynamic fluid blowout prevention function and a method of use to solve the above problems. Summary of the invention

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a blowout preventer with dynamic fluid blowout prevention function and a method of use, so as to solve the problems raised in the above background technology. The present invention has a reasonable structure, performs blowout prevention buffer protection for dynamic fluid, the buffer structure is in the same direction as the fluid flow direction, the fluid pressure is fully released, and the blowout prevention effect is significant.

[0006] In order to achieve the above object, the present invention is implemented through the following technical solutions: a blowout preventer with dynamic fluid blowout prevention function, comprising a radial flow pipe, flanges are arranged at both ends of the radial flow pipe, a radial blowout prevention mechanism for buffering sudden pressure of the fluid is arranged on the radial flow pipe, and a unidirectional blowout prevention mechanism for buffering sudden pressure of unidirectional flowing fluid is arranged on the radial flow pipe;

[0007] The radial blowout prevention mechanism comprises a protective shell and an annular buffer rubber pad, wherein the protective shell is arranged on the radial flow pipe, the annular buffer rubber pad is arranged on the inner side of the protective shell, a plurality of shrinkage grooves are opened inside the annular buffer rubber pad, and an elastic steel sheet is arranged inside the annular buffer rubber pad;

[0008] The one-way blowout prevention mechanism comprises a spring, a piston and a guide tube, wherein the guide tube is arranged on the radial tube, the piston is arranged in the guide tube, a spring rod is arranged at one end of the piston, the spring sleeve is arranged on the spring rod, and the one-way blowout prevention mechanism is provided with at least two groups, and the two groups of one-way blowout prevention mechanisms are centrally symmetrical about the radial tube.

[0009] Furthermore, the cross-section of the annular buffer rubber pad along the axial direction is an inwardly concave arc-shaped structure, the annular buffer rubber pad is a detachable structure, and a sealing rubber pad is arranged on the inner side of the annular buffer rubber pad.

[0010] Furthermore, two end faces of the annular buffer rubber pad are provided with splicing ears, and the inner wall of the protective shell is provided with a splicing groove, and the splicing ears match the splicing groove.

[0011] Furthermore, splicing screws are arranged on both sides of the protective shell, and the splicing screws penetrate the protective shell and are screwed together with the splicing ears, and a breathing hole is opened through the circumferential wall of the protective shell.

[0012] Furthermore, the spacings between the plurality of shrinkage grooves are the same, and the plane where the shrinkage grooves are located is perpendicular to the axis of the annular buffer rubber pad.

[0013] Furthermore, the guide tube includes a piston tube and a flow guide tube which are interconnected, the piston tube matches the piston, the flow guide tube and the radial flow tube are interconnected, and the angle between the center line of the flow guide tube and the center line of the radial flow tube is 5-45°.

[0014] Furthermore, one end of the spring rod passes through the piston tube, a sliding sleeve is sleeved on the spring rod, and the spring rod is slidably connected to the piston tube via the sliding sleeve.

[0015] Furthermore, a support ring is provided inside the piston, and the support rod is fixedly connected to the spring rod, and one end of the piston away from the spring rod is a spherical structure with a concave surface.

[0016] Furthermore, a method for using a blowout preventer having a dynamic fluid blowout prevention function of the present invention comprises the following steps:

[0017] Step S1, connecting the two ends of the runoff pipe to the external wellhead pipeline through flanges, and letting fluid flow into the runoff pipe;

[0018] Step S2, when the fluid pressure in the radial pipe suddenly increases, the fluid flowing through the two ends of the radial pipe squeezes the annular buffer rubber pad, and the annular buffer rubber pad is deformed by force and expands toward the outer circumference, and the annular buffer rubber pad expands and deforms toward the outer circumference side along the contraction groove;

[0019] Step S2-1, the shrinkage groove absorbs part of the pressure due to extrusion deformation, and the shrinkage groove shrinks;

[0020] Step S2-2, the elastic steel sheet is then subjected to the deformation pressure of the annular buffer rubber pad, the elastic steel sheet deforms along with the annular buffer rubber pad, the annular buffer rubber pad bulges outwardly, and the annular buffer rubber pad absorbs a part of the deformation pressure;

[0021] Step S2-3, at the same time, the space between the outer circumferential wall of the annular buffer rubber pad and the inner wall of the protective shell is squeezed and becomes smaller, and the air inside the protective shell is squeezed and discharged from the breathing hole;

[0022] Step S3, when the fluid pressure in the radial pipe is suddenly reduced, the volume of the fluid flowing through the two ends of the radial pipe shrinks, the annular buffer rubber pad is squeezed and deformed due to the negative pressure, the annular buffer rubber pad shrinks toward the inner circumference, and the annular buffer rubber pad shrinks and deforms toward the inner circumference along the shrinkage groove;

[0023] Step S3-1, the shrinkage groove deforms to absorb part of the pressure, and the shrinkage groove expands;

[0024] Step S3-2, the elastic steel sheet is then subjected to the deformation pressure of the annular buffer rubber pad and changes, and is concave toward the inner circumference to absorb a part of the deformation pressure;

[0025] Step S3-3, at the same time, as the annular buffer rubber pad shrinks toward the inner circumference, the space between the outer circumferential wall of the annular buffer rubber pad and the inner wall of the protective shell increases due to the shrinkage of the annular buffer rubber pad, and the air outside the protective shell is squeezed and inhaled from the breathing hole for compensation;

[0026] Step S4, when the fluid in the radial pipe is in a flowing state, the fluid flows toward one direction of the radial pipe, and the fluid enters the guide pipe with an acute flow angle;

[0027] Step S4-1, when the pressure of the flowing fluid in the radial pipe suddenly increases, the dynamic fluid squeezes the guide pipe in the flow direction, and the piston in the guide pipe slides under the squeeze, and the space in the guide pipe increases;

[0028] Step S4-2, the guide tube and the runoff tube are in communication, and after the piston is squeezed and slides, the runoff space of the fluid increases, the fluid pressure decreases, and the fluid pressure is buffered;

[0029] Step S5, when the pressure of the flowing fluid in the radial pipe suddenly decreases, the dynamic fluid is discharged from the guide pipe in the flow direction, the fluid space in the guide pipe is reduced, the pressure of the dynamic fluid is compensated, the fluid pressure increases, and the fluid pressure is buffered.

[0030] Further, in step S4-1, when the pressure of the flowing fluid in the radial flow pipe suddenly increases, the fluid flowing through the two ends of the radial flow pipe squeezes the annular buffer rubber pad, and the annular buffer rubber pad is deformed by force to expand toward the outer circumference, and the annular buffer rubber pad expands and deforms toward the outer circumference along the contraction groove; the contraction groove absorbs part of the pressure due to the compression deformation, and the contraction groove shrinks; then the elastic steel sheet is subjected to the deformation pressure of the annular buffer rubber pad, the elastic steel sheet deforms along with the annular buffer rubber pad, the annular buffer rubber pad bulges toward the outer circumference, and the annular buffer rubber pad absorbs part of the deformation pressure; at the same time, the space between the outer circumferential wall of the annular buffer rubber pad and the inner wall of the protective shell is squeezed and becomes smaller, and the air inside the protective shell is squeezed and discharged from the breathing hole;

[0031] In step S5, when the pressure of the flowing fluid in the flow tube suddenly decreases, the volume of the fluid flowing through the two ends of the flow tube shrinks, the annular buffer rubber pad is squeezed and deformed due to the negative pressure, the annular buffer rubber pad shrinks toward the inner circumference, and the annular buffer rubber pad shrinks and deforms toward the inner circumference along the shrinkage groove; the shrinkage groove deforms to absorb part of the pressure, and the shrinkage groove expands; then the elastic steel sheet follows the deformation pressure of the annular buffer rubber pad and is concave toward the inner circumference to absorb part of the deformation pressure; at the same time, since the annular buffer rubber pad shrinks toward the inner circumference, the space between the outer circumferential wall of the annular buffer rubber pad and the inner wall of the protective shell increases due to the shrinkage of the annular buffer rubber pad, and the air outside the protective shell is squeezed and inhaled from the breathing hole for compensation.

[0032] Beneficial effects of the present invention:

[0033] 1. The addition of the radial blowout prevention mechanism of the present invention can buffer the sudden change of fluid pressure and buffer the pressure change in the radial direction of static or dynamic fluid;

[0034] 2. The addition of the one-way blowout prevention mechanism of the present invention can buffer the sudden change in pressure of the one-way flowing fluid. When the fluid is flowing, the guide tube and the internal piston can buffer the impact force along the direction of the fluid;

[0035] 3. The guide tube of the present invention includes a piston tube and a flow guide tube which are interpenetrating with each other. The piston tube matches the piston 34. The flow guide tube and the flow path tube are interpenetrating with each other. The included angle between the center line of the flow guide tube and the center line of the flow path tube is 5-45°. In this way, the fluid can be smoothly connected with the guide tube which has an acute flow angle. The fluid can directly enter the guide tube for buffering, thereby reducing the resistance of the fluid flow direction change.

[0036] 4. The present invention provides blowout prevention and buffering protection for dynamic fluids. The buffering structure has the same flow direction as the fluid, and the fluid pressure is fully and slowly released, resulting in a significant blowout prevention effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0038] Figure 1 It is a structural schematic diagram of a blowout preventer with dynamic fluid blowout prevention function according to the present invention;

[0039] Figure 2 It is a front cross-sectional view of a blowout preventer with dynamic fluid blowout prevention function according to the present invention;

[0040] Figure 3 for Figure 2 A magnified view of middle;

[0041] In the figure: 1 radial flow pipe, 11 flange, 2 radial blowout prevention mechanism, 21 breathing hole, 22 shell, 221 splicing screw, 23 annular buffer rubber pad, 231 elastic steel sheet, 232 shrinkage groove, 24 sealing rubber pad, 3 one-way blowout prevention mechanism, 31 spring rod, 311 sliding sleeve, 32 spring, 33 support sheet, 34 piston, 35 guide pipe, 351 guide pipe, 352 piston pipe. DETAILED DESCRIPTION

[0042] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0043] See also Figure 1-Figure 3 The present invention provides a technical solution: a blowout preventer with dynamic fluid blowout prevention function, comprising a radial pipe 1, flanges 11 are arranged at both ends of the radial pipe 1, a radial blowout preventer 2 for buffering sudden pressure changes of the fluid is arranged on the radial pipe 1, and a one-way blowout preventer 3 for buffering sudden pressure changes of the unidirectional flowing fluid is arranged on the radial pipe 1. The radial blowout preventer 2 buffers the pressure change in the radial direction of the fluid, and the one-way blowout preventer 3 buffers the fluid in the flowing state. The guide pipe 35 and the internal piston 34 can buffer the impact force along the flow direction of the fluid, which solves the problem that the buffer component of the wellhead blowout preventer in the past oil pipeline is not in the same direction as the fluid flow direction, the buffering effect is not reasonable, and the blowout prevention effect is poor.

[0044] The radial blowout prevention mechanism 2 of the present invention includes a protective shell 22 and an annular buffer rubber pad 23. The protective shell 22 is arranged on the radial flow pipe 1, and the annular buffer rubber pad 23 is arranged on the inner side of the protective shell 22. A plurality of contraction grooves 232 are opened inside the annular buffer rubber pad 23, and an elastic steel sheet 231 is arranged inside the annular buffer rubber pad 23. The radial blowout prevention mechanism 2 can buffer the sudden change of fluid pressure and buffer the pressure change in the radial direction of the static or dynamic fluid.

[0045] The one-way blowout prevention mechanism 3 of the present invention comprises a spring 32, a piston 34 and a guide tube 35. The guide tube 35 is arranged on the radial tube 1, and the piston 34 is arranged in the guide tube 35. A spring rod 31 is arranged at one end of the piston 34, and the spring 32 is sleeved on the spring rod 31. The one-way blowout prevention mechanism 3 buffers the sudden pressure change of the one-way flowing fluid. When the fluid is in a flowing state, the guide tube 35 and the piston 34 inside can buffer the impact force along the direction of the fluid.

[0046] The cross-section of the annular buffer rubber pad 23 along the axial direction of the present invention is an inwardly concave arc-shaped structure. The annular buffer rubber pad 23 is a detachable structure, which can enhance the deformation effect and energy absorption effect of the annular buffer rubber pad 23. A sealing rubber pad 24 is arranged on the inner side of the annular buffer rubber pad 23, and the sealing effect of the annular buffer rubber pad 23 is not affected when the buffering deformation occurs.

[0047] The two end faces of the annular buffer rubber pad 23 of the present invention are provided with splicing ears, the inner wall of the protective shell 22 is provided with a splicing groove, and the splicing ears match the splicing groove, and the two sides of the protective shell 22 are provided with splicing screws 221, and the splicing screws 221 penetrate the protective shell 22 and are screwed together with the splicing ears, so as to facilitate the disassembly and assembly of the annular buffer rubber pad 23;

[0048] A breathing hole 21 is formed through the circumferential wall of the protective shell 22 to allow the air in the protective shell 22 to be discharged in time or to be sucked in and replenished in time during the deformation of the annular buffer rubber pad 23 .

[0049] The spacing between the several contraction grooves 232 of the present invention is the same, the plane where the contraction grooves 232 are located is perpendicular to the axis of the annular buffer rubber pad 23, the contraction grooves 232 make the annular buffer rubber pad 23 deform evenly, and the contraction grooves 232 can absorb part of the elastic potential energy when expanding or squeezing and contracting.

[0050] The guide tube 35 of the present invention includes a piston tube 352 and a guide tube 351 which are interconnected. The piston tube 352 matches the piston 34. The guide tube 351 and the radial tube 1 are interconnected, and the angle between the center line of the guide tube 351 and the center line of the radial tube 1 is 5-45°. In this way, the fluid will be smoothly connected with the guide tube 35 with an acute flow angle, and the fluid can directly enter the guide tube 35 for buffering, thereby reducing the resistance to the change of the fluid flow direction.

[0051] One end of the spring rod 31 of the present invention passes through the piston tube 352. A sliding sleeve 311 is sleeved on the spring rod 31. The spring rod 31 is slidably connected to the piston tube 352 through the sliding sleeve 311, so that the piston 34 moves left and right along the spring rod 31, which plays a role of limiting.

[0052] The piston 34 of the present invention is provided with a support ring inside, and the support rod is fixedly connected to the spring rod 31. The end of the piston 34 away from the spring rod 31 is a spherical structure with a concave surface, which increases the bearing area.

[0053] As an embodiment of the present invention: first, the two ends of the radial pipe 1 are connected to the external wellhead pipeline through the flange 11, and the radial pipe 1 is passed with fluid; when the fluid pressure in the radial pipe 1 suddenly increases, the fluid flowing through the two ends of the radial pipe 1 squeezes the annular buffer rubber pad 23, and the annular buffer rubber pad 23 is deformed by force and expands toward the outer circumference, and the annular buffer rubber pad 23 expands and deforms toward the outer circumference side along the contraction groove 232;

[0054] The shrinkage groove 232 is deformed by extrusion and absorbs part of the pressure, and the shrinkage groove 232 shrinks; then the elastic steel sheet 231 is affected by the deformation pressure of the annular buffer rubber pad 23, and the elastic steel sheet 231 deforms along with the annular buffer rubber pad 23, and the annular buffer rubber pad 23 bulges toward the outer circumference, and the annular buffer rubber pad 23 absorbs part of the deformation pressure; at the same time, the space between the outer circumferential wall of the annular buffer rubber pad 23 and the inner wall of the protective shell 22 is squeezed and becomes smaller, and the air inside the protective shell 22 is squeezed and discharged from the breathing hole 21.

[0055] As an embodiment of the present invention: when the fluid pressure in the radial pipe 1 is suddenly reduced, the volume of the fluid flowing through the two ends of the radial pipe 1 shrinks, the annular buffer rubber pad 23 is squeezed and deformed due to the negative pressure, the annular buffer rubber pad 23 shrinks toward the inner circumference, and the annular buffer rubber pad 23 shrinks and deforms toward the inner circumference along the shrinkage groove 232;

[0056] The shrinkage groove 232 deforms to absorb part of the pressure, and the shrinkage groove 232 expands; then the elastic steel sheet 231 follows the deformation pressure of the annular buffer rubber pad 23 and concaves toward the inner circumference to absorb part of the deformation pressure; at the same time, since the annular buffer rubber pad 23 shrinks toward the inner circumference, the space between the outer circumferential wall of the annular buffer rubber pad 23 and the inner wall of the protective shell 22 increases due to the shrinkage of the annular buffer rubber pad 23, and the air outside the protective shell 22 is squeezed and inhaled from the breathing hole 21 for compensation.

[0057] As an embodiment of the present invention: when the fluid in the radial pipe 1 is in a flowing state, the fluid flows in one direction toward the radial pipe 1, and the fluid enters the guide pipe 35 whose flow direction angle is an acute angle;

[0058] When the pressure of the flowing fluid in the radial pipe 1 suddenly increases, the dynamic fluid squeezes the guide pipe 35 in the flow direction, and the piston 34 in the guide pipe 35 is squeezed and slides, and the space in the guide pipe 35 increases; the guide pipe 35 is in communication with the radial pipe 1, and the piston 34 is squeezed and slides, and the fluid radial space increases, the fluid pressure decreases, and the fluid pressure is buffered;

[0059] Moreover, when the pressure of the flowing fluid in the radial pipe 1 suddenly increases, the fluid flowing through the two ends of the radial pipe 1 squeezes the annular buffer rubber pad 23, and the annular buffer rubber pad 23 is deformed by the force and expands toward the outer circumference, and the annular buffer rubber pad 23 expands and deforms toward the outer circumference along the contraction groove 232; the contraction groove 232 absorbs part of the pressure due to the compression and deformation, and the contraction groove 232 shrinks; then the elastic steel sheet 231 is affected by the deformation pressure of the annular buffer rubber pad 23, the elastic steel sheet 231 deforms along the annular buffer rubber pad 23, the annular buffer rubber pad 23 bulges toward the outer circumference, and the annular buffer rubber pad 23 absorbs part of the deformation pressure; at the same time, the space between the outer circumferential wall of the annular buffer rubber pad 23 and the inner wall of the protective shell 22 is squeezed and becomes smaller, and the air inside the protective shell 22 is squeezed and discharged from the breathing hole 21.

[0060] As an embodiment of the present invention: when the pressure of the flowing fluid in the radial flow pipe 1 is suddenly reduced, the dynamic fluid is discharged from the guide pipe 35 in the flow direction, the fluid space in the guide pipe 35 is reduced, the pressure of the dynamic fluid is compensated, the fluid pressure is increased, and the fluid pressure is buffered;

[0061] Moreover, when the pressure of the flowing fluid in the radial pipe 1 suddenly decreases, the volume of the fluid flowing through the two ends of the radial pipe 1 shrinks, and the annular buffer rubber pad 23 is squeezed and deformed due to the negative pressure, and the annular buffer rubber pad 23 shrinks toward the inner circumference, and the annular buffer rubber pad 23 shrinks and deforms toward the inner circumference along the shrinkage groove 232; the shrinkage groove 232 deforms to absorb part of the pressure, and the shrinkage groove 232 expands; then the elastic steel sheet 231 follows the change of the deformation pressure of the annular buffer rubber pad 23, and is concave toward the inner circumference to absorb part of the deformation pressure; at the same time, since the annular buffer rubber pad 23 shrinks toward the inner circumference, the space between the outer circumferential wall of the annular buffer rubber pad 23 and the inner wall of the protective shell 22 increases due to the shrinkage of the annular buffer rubber pad 23, and the air outside the protective shell 22 is squeezed and inhaled from the breathing hole 21 for compensation.

[0062] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0063] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A blowout preventer with a dynamic fluid blowout prevention function, comprising a flow pipe (1), wherein flanges (11) are provided at both ends of the flow pipe (1), and wherein: The radial flow pipe (1) is provided with a radial blowout prevention mechanism (2) for buffering sudden changes in fluid pressure, and the radial flow pipe (1) is provided with a unidirectional blowout prevention mechanism (3) for buffering sudden changes in fluid pressure flowing in one direction; The radial blowout prevention mechanism (2) comprises a protective shell (22) and an annular buffer rubber pad (23), wherein the protective shell (22) is arranged on the radial flow pipe (1), the annular buffer rubber pad (23) is arranged inside the protective shell (22), a plurality of shrinkage grooves (232) are provided inside the annular buffer rubber pad (23), and an elastic steel sheet (231) is provided inside the annular buffer rubber pad (23); The one-way blowout prevention mechanism (3) comprises a spring (32), a piston (34) and a guide tube (35); the guide tube (35) is arranged on the radial tube (1); the piston (34) is arranged in the guide tube (35); a spring rod (31) is arranged at one end of the piston (34); the spring (32) is sleeved on the spring rod (31); the one-way blowout prevention mechanism (3) is provided with at least two groups; the two groups of one-way blowout prevention mechanisms (3) are centrally symmetrical with respect to the radial tube (1); The cross section of the annular buffer rubber pad (23) along the axial direction is an inwardly concave arc-shaped structure. The annular buffer rubber pad (23) is a detachable structure. A sealing rubber pad (24) is arranged inside the annular buffer rubber pad (23). Two end surfaces of the annular buffer rubber pad (23) are provided with splicing ears. The inner wall of the protective shell (22) is provided with a splicing groove, and the splicing ear matches the splicing groove. Splicing screws (221) are provided on both sides of the protective shell (22), and the splicing screws (221) penetrate the protective shell (22) and are screwed together with the splicing ears, and a breathing hole (21) is provided through the circumferential wall of the protective shell (22); The spacing between the plurality of contraction grooves (232) is the same, and the plane where the contraction grooves (232) are located is perpendicular to the axis of the annular buffer rubber pad (23); The guide tube (35) comprises a piston tube (352) and a flow guide tube (351) which are interconnected, the piston tube (352) matches the piston (34), the flow guide tube (351) and the flow runner tube (1) are interconnected, and the included angle between the center line of the flow guide tube (351) and the center line of the flow runner tube (1) is 5-45°; One end of the spring rod (31) passes through the piston tube (352); a sliding sleeve (311) is sleeved on the spring rod (31); the spring rod (31) is slidably connected to the piston tube (352) via the sliding sleeve (311); a support rod is provided inside the piston (34); the support rod is fixedly connected to the spring rod (31); and one end of the piston (34) facing away from the spring rod (31) is a spherical structure with a concave surface.

2. A method for using a blowout preventer with dynamic fluid blowout prevention function according to claim 1, characterized in that: The steps include: Step S1, connecting the two ends of the runoff pipe (1) to an external wellhead pipeline via flanges (11), and allowing fluid to flow into the runoff pipe (1); Step S2, when the fluid pressure in the radial flow pipe (1) suddenly increases, the fluid flowing through the two ends of the radial flow pipe (1) squeezes the annular buffer rubber pad (23), and the annular buffer rubber pad (23) is deformed by the force and expands toward the outer circumference, and the annular buffer rubber pad (23) expands and deforms toward the outer circumference along the contraction groove (232); Step S2-1, the shrinkage groove (232) is deformed by extrusion to absorb a portion of the pressure, and the shrinkage groove (232) is reduced; Step S2-2, the elastic steel sheet (231) is then subjected to the deformation pressure of the annular buffer rubber pad (23), the elastic steel sheet (231) deforms along with the annular buffer rubber pad (23), the annular buffer rubber pad (23) bulges outwardly, and the annular buffer rubber pad (23) absorbs a portion of the deformation pressure; Step S2-3, at the same time, the space between the outer circumferential wall of the annular buffer rubber pad (23) and the inner wall of the protective shell (22) is squeezed and becomes smaller, and the air inside the protective shell (22) is squeezed and discharged from the breathing hole (21); Step S3, when the fluid pressure in the radial flow tube (1) is suddenly reduced, the volume of the fluid flowing through the two ends of the radial flow tube (1) shrinks, the annular buffer rubber pad (23) is squeezed and deformed due to the negative pressure, the annular buffer rubber pad (23) shrinks toward the inner circumference, and the annular buffer rubber pad (23) shrinks and deforms toward the inner circumference along the shrinkage groove (232); Step S3-1, the shrinkage groove (232) deforms to absorb a portion of the pressure, and the shrinkage groove (232) expands; Step S3-2, the elastic steel sheet (231) is then subjected to the deformation pressure of the annular buffer rubber pad (23) and changes, and is concave toward the inner circumference, thereby absorbing a part of the deformation pressure; Step S3-3, at the same time, as the annular buffer rubber pad (23) shrinks inwardly, the space between the outer circumferential wall of the annular buffer rubber pad (23) and the inner wall of the protective shell (22) increases due to the shrinkage of the annular buffer rubber pad (23), and the air outside the protective shell (22) is squeezed and sucked in through the breathing hole (21) for compensation; Step S4, when the fluid in the radial flow pipe (1) is in a flowing state, the fluid flows in one direction toward the radial flow pipe (1), and the fluid enters the guide pipe (35) whose flow direction angle is an acute angle; Step S4-1, when the pressure of the flowing fluid in the radial pipe (1) suddenly increases, the dynamic fluid squeezes the guide pipe (35) in the flow direction, and the piston (34) in the guide pipe (35) slides under the squeezing, and the space in the guide pipe (35) increases; Step S4-2, the guide tube (35) is in communication with the runoff tube (1), and after the piston (34) is squeezed and slides, the runoff space of the fluid increases, the fluid pressure decreases, and the fluid pressure is buffered; Step S5, when the pressure of the flowing fluid in the radial pipe (1) suddenly decreases, the dynamic fluid is discharged from the guide pipe (35) in the flow direction, the fluid space in the guide pipe (35) decreases, the pressure of the dynamic fluid is compensated, the fluid pressure increases, and the fluid pressure is buffered.

3. The method for using a blowout preventer with dynamic fluid blowout prevention function according to claim 2, characterized in that: In step S4-1, when the pressure of the flowing fluid in the radial flow tube (1) suddenly increases, the fluid flowing through the two ends of the radial flow tube (1) squeezes the annular buffer rubber pad (23), and the annular buffer rubber pad (23) is deformed by force and expands toward the outer circumference. The annular buffer rubber pad (23) expands and deforms toward the outer circumference along the contraction groove (232); the contraction groove (232) absorbs a part of the pressure due to the compression and deformation, and the contraction groove (232) shrinks; then the elastic steel sheet (231) is subjected to the deformation pressure of the annular buffer rubber pad (23), and the elastic steel sheet (231) deforms along with the annular buffer rubber pad (23), and the annular buffer rubber pad (23) bulges toward the outer circumference, and the annular buffer rubber pad (23) absorbs a part of the deformation pressure; at the same time, the space between the outer circumferential wall of the annular buffer rubber pad (23) and the inner wall of the protective shell (22) is squeezed and becomes smaller, and the air inside the protective shell (22) is squeezed and discharged from the breathing hole (21); In step S5, when the pressure of the flowing fluid in the radial flow tube (1) suddenly decreases, the volume of the fluid flowing through the two ends of the radial flow tube (1) shrinks, the annular buffer rubber pad (23) is squeezed and deformed due to the negative pressure, the annular buffer rubber pad (23) shrinks toward the inner circumference, and the annular buffer rubber pad (23) shrinks and deforms toward the inner circumference along the shrinkage groove (232); the shrinkage groove (232) deforms to absorb a part of the pressure, and the shrinkage groove (232) expands; then the elastic steel sheet (231) follows the deformation pressure of the annular buffer rubber pad (23) and is concave toward the inner circumference to absorb a part of the deformation pressure; at the same time, due to the shrinkage of the annular buffer rubber pad (23) toward the inner circumference, the space between the outer circumferential wall of the annular buffer rubber pad (23) and the inner wall of the protective shell (22) increases due to the shrinkage of the annular buffer rubber pad (23), and the air outside the protective shell (22) is squeezed and sucked in from the breathing hole (21) for compensation.

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