A clip-type continuous ball throwing device

Abstract

The present invention provides a clip-type continuous ball thrower, comprising a lower cover, a main body with a horizontal accommodating space, a side door, two plungers, a piston and two ball-containing tubes; the lower end of the main body is provided with a vertical channel connected to the horizontal accommodating space, and the outlet of the vertical channel is provided with a lower cover; the side of the main body is provided with a side hole connected to the vertical channel; the fracturing balls are stored in the two ball-containing tubes; the lower ends of the two ball-containing tubes are connected to the horizontal accommodating space, and the two plungers are respectively connected to the two ends of the piston, and the two plungers are driven by the hydraulic control system to perform linear motion, pushing the piston to move left and right, and the fracturing balls enter the through hole of the piston under the action of gravity, and then enter the vertical channel and are thrown out from the side hole. The ball thrower of the present invention has a simple structure and a small size, does not occupy the main pipe column interface of the wellhead pressure control device, and solves the installation problem; and through the external hydraulic control system, the functions of continuous ball throwing and remote operation can be realized.

Description

Technical Field

[0001] The invention relates to downhole fracturing equipment in the field of shale gas production and drainage, and in particular to a clip-type continuous ball thrower. Background Art

[0002] Shale gas is a natural gas resource that can be mined in shale layers. With the substantial increase in shale gas production in the United States, it has achieved energy independence and even achieved energy export, making shale gas widely concerned around the world. The innovation of shale gas exploration and mining technology has greatly promoted the increase of shale gas production in the United States. The abundant reserves and economic feasibility of the United States have also accelerated the commercialization of shale gas. At the same time, in order to cope with climate change and reduce carbon emissions, vigorously developing shale gas can reduce the high dependence on high-carbon emission coal and oil. Therefore, the development of shale gas has far-reaching significance for my country's economic development and environmental protection.

[0003] As a country with rich shale gas reserves, my country has built a number of high-yield shale gas fields, including the Fuling shale gas field, Weiyuan shale gas field, Weirong shale gas field, Changning shale gas field, Luzhou shale gas field, and Southern Sichuan shale gas field.

[0004] Shale gas exists in organic-rich mudstone and its interlayers in an adsorbed and free state. To increase production capacity, the development of more than 85% of shale gas fields in the United States requires the use of horizontal wells and staged fracturing technology. This technology has also made great progress in my country. At present, my country's staged pressure technology and equipment localization have achieved excellent results. However, the performance and operation methods of some equipment still need to be improved.

[0005] The full-bore bridge plug used in staged fracturing operations needs to be used in conjunction with the fracturing ball to achieve the purpose of staged plugging of the wellbore. Simply put, the full-bore bridge plug is like the valve seat of a one-way valve, and the fracturing ball is like the ball of a one-way valve.

[0006] In staged fracturing operations, cable operation or continuous tubing operation is usually used, or cross operation is used. In the early stage of ball dropping operations, it was necessary to disassemble a connection port of the pressure control equipment at the wellhead, manually drop the ball, and then reconnect the port. This operation method has the following problems:

[0007] 1. Each time you pitch, you need to dismantle and install the high-voltage connection unit, such as flanges and unions;

[0008] 2. Manual throwing requires personnel to climb to the operating platform at the wellhead, and the operators are in a dangerous environment of high-altitude operation; remote operation is not possible.

[0009] After searching, it was found that the Chinese patent with application number 201620172761X disclosed an automatic ball thrower for horizontal well stratified fracturing, which solved the purpose of remote operation and continuous ball throwing. However, other equipment at the wellhead must be removed and the ball thrower must be installed at the wellhead to achieve the above function. In addition, the equipment is large in size, complex in structure, and can only accommodate a limited number of fracturing balls.

[0010] The Chinese patent application number 2013206951001 discloses a balanced mechanical ball thrower, but the patent does not solve the problem of remote operation, only continuous ball throwing. In addition, other equipment at the wellhead must be removed and the ball thrower must be installed at the wellhead to achieve the purpose of continuous ball throwing, and the number of fracturing balls that can be accommodated is limited.

[0011] The Chinese patent with application number 2013104736170 discloses a full range of large-capacity automatic ball loading digitally controlled staged fracturing ball throwers, which realizes operations similar to the automatic tool change tool holder of a machining center, and achieves the purpose of large capacity, continuous ball throwing, remote operation, and automatic ball selection (fracturing balls of any size can be thrown). However, this high-pressure pressure-bearing equipment with an integrated "automatic ball selection system" also integrates an AC digital servo motor, a programming controller and a position sensor, a chain transmission system, etc. in addition to the pressure-bearing equipment. If the electronic equipment used in this system is used in field construction sites in Sichuan, Chongqing, Yunnan and other regions, the air is humid, which is not conducive to the stable operation of high-precision electronic equipment. In order to pursue good explosion-proof and protection requirements, it will greatly increase production costs. However, the arbitrary ball selection function pursued above is unnecessary, because the order of most ball throwing operations is to throw balls in order from small to large. Summary of the invention

[0012] In view of the defects in the prior art, the purpose of the present invention is to provide a clip-type continuous ball throwing device, which achieves low cost, continuous ball throwing, remote operation and does not occupy the main wellhead.

[0013] In order to solve the above problems, the present invention provides a clip-type continuous ball throwing device, comprising:

[0014] A main body, wherein the main body has a horizontal accommodating space with open ends, and a first side door and a second side door are respectively provided at both ends of the horizontal accommodating space to close the open end of the horizontal accommodating space; a first inlet and a second inlet are provided at the upper end of the main body to communicate with the horizontal accommodating space; a vertical channel is provided at the lower end of the main body to communicate with the horizontal accommodating space, and a lower cover is provided at the outlet of the vertical channel; a side hole is provided on the side of the main body to communicate with the vertical channel;

[0015] A first ball receiving tube and a second ball receiving tube connected to the first inlet and the second inlet respectively, wherein the first ball receiving tube and the second ball receiving tube are provided with a columnar space for accommodating a fracturing ball; the columnar space is vertically arranged above the horizontal accommodating space and is arranged at a right angle to the horizontal accommodating space, and the fracturing ball can enter the horizontal accommodating space under the action of gravity;

[0016] A first plunger and a second plunger are disposed in the horizontal accommodating space, the first plunger and the second plunger are arranged along the axial direction of the horizontal accommodating space, one end of the first plunger and the second plunger are connected to the first side door and the second side door respectively; the first plunger and the second plunger are connected to an external hydraulic control system;

[0017] A piston is arranged in the horizontal accommodating space, and one end of the piston is provided with a first socket for inserting the first plunger, and the other end of the piston is provided with a second socket for inserting the second plunger; the piston is driven by the hydraulic control system to move left and right; the piston is provided with a through hole that can accommodate the fracturing ball; the piston moves left and right, so that the through hole moves to below the first inlet or the second inlet, and the fracturing ball enters the through hole from the first inlet or the second inlet, and the piston moves so that the through hole moves to above the vertical channel, and the fracturing ball enters the vertical channel under the action of gravity and is thrown out from the side hole.

[0018] Preferably, the side hole is arranged at an acute angle to the horizontal direction, and the outlet of the side hole is located below the inlet.

[0019] Preferably, the upper end of the lower cover is provided with an inclined surface, and the inclined surface is smoothly connected to the side hole.

[0020] Preferably, the lower cover is connected to the main body via a first hexagon socket screw.

[0021] Preferably, the upper end surface of the piston is provided with a groove for accommodating the fracturing ball to be thrown.

[0022] Preferably, both ends of the columnar space of the first ball-containing tube and the second ball-containing tube are open, one end of which is provided with a thread for connecting the first inlet and the second inlet, and the other end is provided with a union and a plug, the union is sleeved on the outer wall of the columnar space, and the plug is inserted into the end of the columnar space to close the end.

[0023] Preferably, the first side door and the second side door are integrally formed with the first plunger and the second plunger respectively; the first side door and the second side door are disc-shaped components with plug-in ends, and the plug-in ends are plugged into the horizontal accommodating space of the main body; the first plunger and the second plunger are provided with a cavity; the disc-shaped component is provided with a hydraulic control interface connected to the cavity, and an external hydraulic control system is connected through the hydraulic control interface, thereby driving the piston to perform linear motion.

[0024] Preferably, the ends of the first plunger and the second plunger are axially provided with a first annular groove for installing a first sealing ring and a second annular groove for installing a second sealing ring, wherein the first sealing ring is located on the outside of the second sealing ring, the first sealing ring is used to seal the hydraulic control pressure, and the second sealing ring is used to seal the wellhead pressure.

[0025] Preferably, the first plunger and the second plunger are provided with axial holes along the axial direction;

[0026] A radial hole communicating with the axial hole is radially arranged at the end of the first plunger and the second plunger, and the radial hole is located between the first sealing ring and the second sealing ring.

[0027] Preferably, the disc-shaped member is provided with a bolt hole for connecting with the main body via a second hexagon socket head screw.

[0028] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0029] The ball thrower of the present invention adopts a double ball-containing tube design, which increases the capacity of fracturing balls while maintaining a compact size. The ball-containing tube can be appropriately adjusted according to specific requirements without affecting other components, so that it has high adaptability. Through the introduction of hydraulic control operation, the functions of continuous ball throwing and remote operation can be realized. Moreover, since the hydraulic control system is widely used in the operation site, it is convenient to use the integrated hydraulic station commonly used in the well site.

[0030] The ball thrower of the present invention has the characteristics of simple structure and compact size, which makes it possible to not occupy the main pipe column interface of the wellhead pressure control device, greatly solves the installation problem, and has low manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] 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:

[0032] Figure 1 is a cross-sectional view of a clip-type continuous ball throwing device according to a preferred embodiment of the present invention;

[0033] Figure 2 yes Figure 1 AA section view;

[0034] Figure 3 is a side view of a clip-type continuous pitching device according to a preferred embodiment of the present invention;

[0035] Figure 4 It is a side view from another angle of the clip-type continuous ball throwing device of a preferred embodiment of the present invention;

[0036] Figure 5 It is a cross-sectional view of the connection between the plunger and the side door of a clip-type continuous ball throwing device according to a preferred embodiment of the present invention;

[0037] Figure 6 It is a schematic diagram of the connection structure between the plunger and the side door of a clip-type continuous ball throwing device according to a preferred embodiment of the present invention;

[0038] Figure 7 It is a schematic diagram of the connection between a clip-type continuous ball throwing device and a blowout preventer according to a preferred embodiment of the present invention;

[0039] The symbols in the figure are respectively represented as: lower cover 1, main body 2, first side door 3, piston 4, first ball tube 5a, second ball tube 5b, fracturing ball 6, union 7, plugging 8, inclined surface 11, first hexagon socket screw 12, first sealing component 13, side hole 22, second hexagon socket screw 23, hydraulic control interface 31, fourth sealing component 32, third hexagon socket screw 33, axial hole 34, second sealing ring 35, radial hole 36, first sealing ring 37, first plunger 38, bolt hole 39, groove 41, first socket 42a, second socket 42b, third sealing component 51, second sealing component 52, clip-type continuous ball thrower 100, and blowout preventer 200. DETAILED DESCRIPTION

[0040] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention. The parts not described in detail in the following embodiments can all be implemented using existing components.

[0041] Reference Figure 1 , which is a cross-sectional view of a clip-type continuous ball thrower according to a preferred embodiment of the present invention, comprising: a main body 2, a first ball receiving tube 5a, a second ball receiving tube 5b, a first plunger 38, a second plunger and a piston 4;

[0042] Among them, the main body 2 has a horizontal accommodating space with open ends, and a first side door 3 and a second side door are respectively provided at both ends of the horizontal accommodating space to close the open end of the horizontal accommodating space; the upper end of the main body 2 is provided with a first inlet and a second inlet connected to the horizontal accommodating space; the lower end of the main body 2 is provided with a vertical channel connected to the horizontal accommodating space, and the outlet of the vertical channel is provided with a lower cover 1; the side of the main body 2 is provided with a side hole 22 connected to the vertical channel, and the side hole 22 is the outlet for throwing the fracturing ball 6.

[0043] The first ball-receiving tube 5a has a columnar space for accommodating the fracturing ball 6. One end of the first ball-receiving tube 5a is connected to the first inlet, and the columnar space of the first ball-receiving tube 5a is connected to the horizontal accommodating space of the main body 2. The second ball-receiving tube 5b has a columnar space for accommodating the fracturing ball 6. The second ball-receiving tube 5b is connected to the second inlet, and the columnar space of the second ball-receiving tube 5b is connected to the horizontal accommodating space of the main body 2. The first ball-receiving tube 5a and the second ball-receiving tube 5b are connected to the top of the main body 2 and are located above the horizontal accommodating space and are arranged at right angles to the horizontal accommodating space. The diameter of the columnar space of the first ball-receiving tube 5a and the second ball-receiving tube 5b matches the diameter of the fracturing ball 6, so that multiple fracturing balls 6 are placed vertically in the first ball-receiving tube 5a and the second ball-receiving tube 5b. The fracturing ball 6 can move downward into the horizontal accommodating space under the action of gravity. The length of the first ball-receiving tube 5a and the second ball-receiving tube 5b can be appropriately adjusted according to the ball-receiving amount requirements without affecting the components. Through reasonable size design, the above-mentioned ball thrower can be applied to fracturing balls 6 of different sizes from 38mm to 60mm without replacing any parts. The double ball-containing tube design increases the capacity of the fracturing ball 6 while maintaining a compact size, and the ball-containing tube can be appropriately adjusted according to specific requirements without affecting other parts, making it highly adaptable.

[0044] The first plunger 38 and the second plunger are disposed in the horizontal accommodating space, and the first plunger 38 and the second plunger are arranged along the axial direction of the horizontal accommodating space. One end of the first plunger 38 and the second plunger are respectively connected to the first side door 3 and the second side door; the first plunger 38 and the second plunger are connected to the external hydraulic control system.

[0045] The piston 4 is arranged in the horizontal accommodation space. A first socket 42a for inserting the first plunger 38 is provided at one end of the piston 4, and a second socket 42b for inserting the second plunger is provided at the other end of the piston 4; the piston 4 can move left and right under the drive of the hydraulic control system on both sides; the piston 4 is provided with a through hole capable of accommodating the fracturing ball 6, and the through hole passes through the piston 4 vertically. The through hole is moved to the bottom of the first inlet or the second inlet by the piston 4 moving left and right, and the fracturing ball 6 enters the through hole from the first inlet or the second inlet, and the through hole is moved to the top of the vertical channel by the movement of the piston 4, and the fracturing ball 6 enters the vertical channel under the action of gravity and is thrown out from the side hole 22. The first plunger 38 and the second plunger are used in conjunction with each other under the drive of the external hydraulic control system to realize the left and right movement of the piston 4, and the fracturing balls 6 in the first ball-containing tube 5a and the second ball-containing tube 5b on the left and right sides are thrown into the well respectively.

[0046] The above-mentioned clip-type continuous ball thrower can realize the functions of continuous ball throwing and remote operation by connecting to an external hydraulic control system. Moreover, since the hydraulic control system is widely used at the operation site, it is convenient to use the integrated hydraulic station commonly used at the well site.

[0047] In other preferred embodiments, refer to Figure 2 , Figure 3 As shown, the side hole 22 is arranged at an acute angle to the horizontal direction, and the outlet of the side hole 22 is located below the inlet. Figure 4 As shown, the side hole 22 can be connected to the side of the wellhead device at any position through the second hexagon socket screw 23 without occupying the main wellhead channel, thereby avoiding subsequent disassembly and assembly operations.

[0048] In other preferred embodiments, refer to Figure 2 As shown, the upper end of the lower cover 1 is provided with a guiding inclined surface 11, and the inclined surface 11 is smoothly connected to the side hole 22. The fracturing ball 6 can enter the side hole 22 by its own gravity under the action of the guiding inclined surface 11 of the lower cover 1. As a preferred embodiment, the lower cover 1 is a component with an inverted T-shaped cross section, and the vertical side of the inverted T-shaped component is inserted into the outlet of the vertical channel. A first sealing component 13 is provided at the connection between the vertical side and the vertical channel, so that the outer wall of the vertical side is tightly matched with the inner wall of the vertical channel. The lower cover 1 is connected to the main body 2 by a first hexagon socket screw 12.

[0049] In other preferred embodiments, refer to Figure 1 As shown, the upper end surface of the piston 4 is provided with a groove 41 for accommodating the fracturing ball 6 to be thrown. Figure 1 As shown, when the fracturing ball 6 located at the bottom enters the through hole of the piston 4 , the part of the fracturing ball 6 adjacent to the fracturing ball 6 enters the groove 41 of the piston 4 .

[0050] In other preferred embodiments, refer to Figure 1As shown, both ends of the columnar space of the first ball-containing tube 5a and the second ball-containing tube 5b are open, and one end thereof is provided with an external thread for connecting the first inlet and the second inlet. A second sealing component 52 is provided at the connection between the columnar space and the first inlet and the second inlet, so that the outer wall of the columnar space and the inner wall of the first inlet and the second inlet are tightly matched. An internal thread matching the external thread is provided on the inner wall of the first inlet and the second inlet. A union 7 and a plug 8 are provided at the other end of the columnar space, and the union 7 is sleeved on the outer wall of the columnar space, and the plug 8 is plugged into the end of the columnar space to close the end. A third sealing component 51 is provided at the connection between the plug 8 and the columnar space, so that the plug 8 and the columnar space are tightly matched.

[0051] In other preferred embodiments, the first side door 3 and the first plunger 38 are integrally formed. The second side door and the second plunger are integrally formed. The first side door 3 and the second side door are disc-shaped components with a plug-in end, and the plug-in end is connected to one end of the first plunger 38 and the second plunger. The plug-in end is inserted into the horizontal accommodation space of the main body 2. A fourth sealing component 32 is provided at the connection position between the plug-in end and the horizontal accommodation space, so that the outer wall of the plug-in end and the inner wall of the horizontal accommodation space of the main body 2 are tightly matched. The first plunger 38 and the second plunger are provided with a cavity; the disc-shaped component is provided with a hydraulic control interface 31 connected to the cavity, and the external hydraulic control system is connected through the hydraulic control interface 31 to push the piston 4 to perform reciprocating linear motion.

[0052] In other preferred embodiments, the first plunger 38 has the same structure as the second plunger. Figure 5 As shown, taking the first plunger 38 as an example, the end of the first plunger 38 is axially provided with a first annular groove for installing the first sealing ring 37 and a second annular groove for installing the second sealing ring 35, wherein the first sealing ring 37 is located on the outside of the second sealing ring 35 (i.e., close to the ends of the first plunger 38 and the second plunger), the first sealing ring 37 is used to seal the hydraulic control pressure, and the second sealing ring 35 is used to seal the wellhead pressure.

[0053] In other preferred embodiments, the first plunger 38 has the same structure as the second plunger. Figure 5 As shown, taking the first plunger 38 as an example, the first plunger 38 is provided with an axial hole 34 in the axial direction; the end of the first plunger 38 is provided with a radial hole 36 in the radial direction which is connected with the axial hole 34, and the radial hole 36 is located between the first sealing ring 37 and the second sealing ring 35. When the first sealing ring 37 or the second sealing ring 35 leaks, it can be directly observed visually from the outside through the axial hole 34.

[0054] In other preferred embodiments, refer to Figure 6As shown, a plurality of bolt holes 39 for passing the third hexagon socket screws 33 are evenly distributed along the circumferential direction on the disc-shaped component. The first side door 3, the second side door and the main body 2 are fixed by the third hexagon socket screws 33.

[0055] Reference Figure 7 As shown, in one application example, the above-mentioned clip-type continuous ball thrower 100 is installed on the side of the wellhead cable blowout preventer 200. In most cases, the wellhead will not remove the blowout preventer 200 before completing the fracturing operation, so the clip-type continuous ball thrower 100 can also be used as an important component of the blowout preventer 200, and can be installed on the side of the blowout preventer 200 in the factory state, and the upper and lower ends of the blowout preventer 200 are connected in series to the main pipe column of the wellhead pressure control equipment.

[0056] All kinds of components used in the application documents, unless otherwise described in detail, may be made of standard parts or commonly used technologies and may be purchased on the market. The specific connection methods of the various parts may adopt conventional means such as mature bolts, rivets and welding in the prior art. Machinery, parts and electrical equipment may adopt conventional models in the prior art, and circuit connections may adopt conventional connection methods in the prior art. These are all very easy to implement for technicians in the relevant field and will not be described in detail here.

[0057] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art may make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A clip-type continuous pitching device, characterized in that: include: A main body, wherein the main body has a horizontal accommodating space with open ends, and a first side door and a second side door are respectively provided at both ends of the horizontal accommodating space to close the open end of the horizontal accommodating space; a first inlet and a second inlet are provided at the upper end of the main body to communicate with the horizontal accommodating space; a vertical channel is provided at the lower end of the main body to communicate with the horizontal accommodating space, and a lower cover is provided at the outlet of the vertical channel; a side hole is provided on the side of the main body to communicate with the vertical channel; A first ball-containing tube and a second ball-containing tube connected to the first inlet and the second inlet respectively, wherein the first ball-containing tube and the second ball-containing tube are provided with a columnar space for accommodating fracturing balls; The columnar space is vertically arranged above the horizontal accommodation space and arranged at a right angle to the horizontal accommodation space, and the fracturing ball can enter the horizontal accommodation space under the action of gravity; A first plunger and a second plunger are disposed in the horizontal accommodating space, the first plunger and the second plunger are arranged along the axial direction of the horizontal accommodating space, one end of the first plunger and the second plunger are connected to the first side door and the second side door respectively; the first plunger and the second plunger are connected to an external hydraulic control system; A piston is arranged in the horizontal accommodation space, one end of the piston is provided with a first socket for inserting the first plunger, and the other end of the piston is provided with a second socket for inserting the second plunger; the piston is driven by the hydraulic control system to move left and right; the piston is provided with a through hole capable of accommodating the fracturing ball; the through hole is moved to the lower side of the first inlet or the second inlet by the left and right movement of the piston, and the fracturing ball enters the through hole from the first inlet or the second inlet, and the through hole is moved to the upper side of the vertical channel by the movement of the piston, and the fracturing ball enters the vertical channel under the action of gravity and is thrown out from the side hole; The side hole is arranged at an acute angle to the horizontal direction, and the outlet of the side hole is located below the inlet; the upper end of the lower cover is provided with an inclined surface, which is smoothly connected to the side hole, and the fracturing ball enters the side hole under the guidance of the inclined surface of the lower cover by its own gravity; the side hole is connected to the side of the wellhead device at any position through the second hexagon socket screw, without occupying the main wellhead channel, avoiding the later disassembly and assembly operation; The upper end surface of the piston is provided with a groove for accommodating the fracturing ball to be thrown; when the fracturing ball located at the bottom enters the through hole of the piston, the fracturing ball part adjacent to the fracturing ball enters the groove.

2. The clip-type continuous ball throwing device according to claim 1, characterized in that: The lower cover is connected to the main body via a first hexagon socket screw.

3. The clip-type continuous ball throwing device according to claim 1, characterized in that: Both ends of the columnar space of the first ball-containing tube and the second ball-containing tube are open, one end of which is provided with a thread for connecting the first inlet and the second inlet, and the other end is provided with a union and a plug, the union is sleeved on the outer wall of the columnar space, and the plug is inserted into the end of the columnar space to close the end.

4. The clip-type continuous ball throwing device according to claim 1, characterized in that: The first side door and the second side door are integrally formed with the first plunger and the second plunger respectively; the first side door and the second side door are disc-shaped components with plug-in ends, and the plug-in ends are plugged into the horizontal accommodating space of the main body; the first plunger and the second plunger are provided with a cavity; the disc-shaped component is provided with a hydraulic control interface connected to the cavity, and an external hydraulic control system is connected through the hydraulic control interface, thereby driving the piston to perform linear motion.

5. The clip-type continuous ball throwing device according to claim 4, characterized in that: A first annular groove for installing a first sealing ring and a second annular groove for installing a second sealing ring are axially provided at the ends of the first plunger and the second plunger, wherein the first sealing ring is located on the outside of the second sealing ring, the first sealing ring is used to seal the hydraulic control pressure, and the second sealing ring is used to seal the wellhead pressure.

6. The clip-type continuous ball throwing device according to claim 5, characterized in that: The first plunger and the second plunger are provided with axial holes along the axial direction; A radial hole communicating with the axial hole is radially arranged at the end of the first plunger and the second plunger, and the radial hole is located between the first sealing ring and the second sealing ring.

7. The clip-type continuous ball throwing device according to claim 4, characterized in that: The disc-shaped component is provided with a bolt hole for connecting with the main body through a second hexagon socket head screw.

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