A ball-carrying rubber sleeve type dissolvable ball seat and setting method

Abstract

The application belongs to the technical field of oil and gas field development, and discloses a ball-carrying rubber sleeve type soluble ball seat and a setting method, wherein the core rod passes through a cone seat, a slip inner core, a lock ring and a base in sequence from top to bottom; one side of the cone seat is provided with a through hole, a soluble ball is arranged in the through hole and abuts against the core rod, a protection ring, a rubber sleeve and a supporting ring are arranged on the outer wall of the cone seat, the lower end of the protection ring abuts against the upper end of the rubber sleeve, the lower end of the rubber sleeve abuts against the upper end of the supporting ring, and the lower end of the supporting ring abuts against the upper end of the slip inner core; one end of the core rod is connected with the cone seat, and the other end is fixedly connected with the base; the rubber sleeve is soluble rubber; the protection ring, the rubber sleeve and the supporting ring are expanded during sliding on the cone seat, are fixed on the inner wall of the casing and form a sealed annular space; after the ball seat is set, the soluble ball seals the central passage of the cone seat under the action of liquid flow, so that pumping and ball-throwing work is saved, and the fracturing operation efficiency is improved.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas field development technology, and relates to a soluble ball seat of the ball-carrying rubber tube type and a setting method. Background Technology

[0002] In the field of oil exploration and development, a key technological step in enhancing oil and gas well productivity is fracturing. This process involves injecting fluids under high pressure into underground rock formations, forcing the rock to fracture and widening the path for oil and gas flow, thereby increasing production. In this complex and delicate operation, fracturing tools, especially fracturing balls, play a crucial role. Previously, fracturing balls were generally constructed from ductile iron, a material with good drillability. While this material possesses certain mechanical strength and wear resistance, additional drilling operations are required to remove the ball after the fracturing operation. This step is not only time-consuming and costly but also adds complexity to the operational process, significantly hindering the overall efficiency of oil extraction.

[0003] Given the limitations of traditional fracturing ball seats, soluble ball seats are used. After fracturing, they automatically dissolve under specific environmental conditions, which not only eliminates the tedious and expensive drilling process, but also significantly shortens the operation cycle and reduces costs. However, the following problems exist: 1) Ball deployment reduces operation efficiency and soluble balls waste fracturing fluid during pumping; 2) The setting of the ball seat cannot be verified. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a soluble ball seat with a ball-carrying rubber sleeve and a setting method. The protective ring, rubber sleeve, and support ring expand during the sliding process on the cone seat, sealing casings of different diameters. After the ball seat is set, the soluble ball seals the internal channel of the base under the action of liquid flow. The sealing performance of the ball seat is tested to improve reliability and save time and materials for ball pumping from the wellhead.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a soluble ball holder with a ball-carrying rubber tube, comprising a core rod that passes through a conical seat, a locking inner core, a locking ring, and a base from top to bottom. A through hole is provided on one side of the conical seat, and a soluble ball is placed inside the through hole and abuts against the core rod. A protective ring, a rubber tube, and a support ring are fitted on the outer wall of the conical seat. The lower end of the protective ring abuts against the upper end of the rubber tube, the lower end of the rubber tube abuts against the upper end of the support ring, and the lower end of the support ring abuts against the upper end of the locking inner core. One end of the core rod is engaged with the conical seat, and the other end is fixedly connected to the base.

[0006] Furthermore, the protective ring, rubber sleeve, and support ring are a combined cylindrical structure with a cylindrical outer surface and a conical hole inside, the diameter of which decreases continuously from top to bottom and abuts against the side wall of the conical seat.

[0007] Furthermore, the cone base is composed of a large outer cylinder, a frustum of a cone, and a small outer cylinder from top to bottom. The cone base has a hollow structure inside, consisting of a large conical hole, a large inner circular hole, a small conical hole, and a small inner circular hole. The through hole is located inside the large outer cylinder and communicates with the large inner circular hole. The depth of the through hole is adapted to the thickness of the large outer circular hole.

[0008] Furthermore, the inner core of the slip is provided with a plurality of first grooves along the circumference, and a large ceramic column is disposed in the first groove for connection with the sleeve; the base is provided with a second groove along the circumference, and a small ceramic column is disposed in the second groove for connection with the sleeve; the cone seat is provided with a third groove along the circumference on the side away from the base, and a small ceramic column is disposed in the third groove for connection with the sleeve.

[0009] Furthermore, the inner core of the clasp is provided with protrusions at both the upper and lower ends. The upper protrusion abuts against the support ring, and the lower protrusion abuts against the base. Both the upper and lower protrusions are fixedly connected to the inner core of the clasp.

[0010] Furthermore, the outer surface of the small outer cylinder is provided with barbs for fixed connection with the locking ring.

[0011] Furthermore, the base is a cylindrical structure with large and small threads on its inner surface. The large thread is fixedly connected to the locking ring, and the small thread is fixedly connected to the core rod.

[0012] Furthermore, the soluble ball, cone seat, protective ring, support ring, slip core, locking ring, and base are made of magnesium-based and aluminum-based soluble metal materials, and the rubber sleeve is soluble rubber that automatically dissolves after crushing.

[0013] This invention also provides a method for setting a soluble ball seat using a ball-carrying rubber sleeve, comprising the following steps: In use, the setting tool pulls the upper end of the core rod, the lower end of the core rod is connected to the base, the base and the inner core of the slip move upward, the diameter of the inner core of the slip continuously expands, the bottom of the cone seat is squeezed into the locking ring, the outer walls of the protective ring, rubber sleeve and support ring abut against the inner wall of the casing to complete the seal, the core rod is pulled further, the core rod and the base move relative to each other and separate, the soluble ball moves into the cone seat under the drive of the fracturing fluid, sealing the inner hole channel, and performing segmented fracturing, the soluble ball automatically dissolves after the fracturing is completed.

[0014] Furthermore, the relative movement and separation between the core rod and the base includes a mismatch in the hardness of the core rod and the base, whereby the core rod separates from the base first under the action of the setting tool, and then is pulled out along the sleeve inlet direction.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects: This invention discloses a soluble ball holder in a ball-carrying sleeve type. The cone seat and the inner core of the slip are a cone-shaped combination structure. The sealing element, protective ring, and support ring seal and fix the casing during the movement of the cone seat. The soluble ball is placed in the through hole. After the core rod separates from the base, under the action of the setting tool, the soluble ball seals the internal channel of the base under the action of liquid flow, saving the work of pumping and dropping balls and improving the efficiency of fracturing operations.

[0016] This invention provides a soluble ball holder in the form of a ball-carrying tube, which not only saves the step of putting soluble balls into the wellhead, but also strengthens the stability of the cone seat, the inner core of the slip, and the base. After the base reaches the predetermined position and is sealed and fixed, the setting and sealing of the base is immediately verified, which improves the reliability of the base construction.

[0017] This invention relates to a soluble ball holder in the form of a ball-carrying rubber tube. The soluble ball, cone seat, protective ring, support ring, inner core of the slip, locking ring, and base are all made of magnesium-based or aluminum-based soluble metal materials, and the rubber tube is made of soluble rubber, which automatically dissolves after crushing.

[0018] This invention relates to a ball-carrying tube type soluble ball seat, in which a large ceramic column is fixed to the side wall of the inner core of the slip, mainly serving an anchoring function. It is embedded in the inner wall of the sleeve to form a stable structure, ensuring that the inner core of the slip and the base can be firmly fixed in the appropriate position. The large ceramic column is designed with a certain angle, which not only helps to better embed in the inner wall of the sleeve, but also provides stronger fixing force, thereby increasing the stability of the entire structure.

[0019] The present invention provides a soluble ball holder in the form of a ball-carrying tube, wherein a small ceramic column is located on the side wall of the cone seat and the base, which can reduce the friction between the cone seat and the base and the well wall during the well running process, thereby extending the service life of these components.

[0020] The present invention provides a soluble ball holder in the form of a ball-carrying tube, which is fixed to the inner wall of the sleeve and can form a sealed annular space. Attached Figure Description

[0021] Figure 1 This is a cross-sectional view of a soluble ball holder of the present invention, which is a ball-carrying rubber tube type. Figure label: 1-Core rod; 2-Soluble ball; 3-Conical seat; 4-Protective ring; 5-Rubber sleeve; 6-Support ring; 7-Clad inner core; 8-Large ceramic column; 9-Small ceramic column; 10-Locking ring; 11-Base. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. 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 should fall within the scope of protection of the present invention.

[0023] Example 1 This invention provides a soluble ball holder in the form of a ball-carrying rubber tube, such as... Figure 1 As shown, the device includes a core rod 1, which is fitted with a conical seat 3, a locking inner core 7, a locking ring 10, and a base 11 from top to bottom. A through hole is provided on one side of the conical seat 3, and a soluble ball 2 is placed in the through hole and abuts against the core rod 1. A protective ring 4, a rubber sleeve 5, and a support ring 6 are fitted on the outer wall of the conical seat 3. The lower end of the protective ring 5 abuts against the upper end of the rubber sleeve 5, the lower end of the rubber sleeve abuts against the upper end of the support ring 6, and the lower end of the support ring 6 abuts against the upper end of the locking inner core 7. One end of the core rod 1 is engaged with the conical seat 3, and the other end is fixedly connected to the base 11.

[0024] During drilling operations, when it is necessary to set the downhole tools, pressure is applied to the core rod 1 using the setting tool. Under pressure, the core rod 1 is securely connected to the base 11 via its external thread, and abuts against the upper end face of the cone seat 3 via the transverse core rod, forming a sealing structure. At this time, the cone seat 3 is compressed by the core rod, converting the setting force into a compressive force on the well wall, thereby achieving the setting function.

[0025] The rubber sleeve 5 is made of soluble rubber, while the soluble ball 2, cone seat 3, protective ring 4, support ring 6, slip inner core 7, locking ring 10, and base 11 are made of magnesium-based and aluminum-based soluble metal materials, which are dissolved after fracturing.

[0026] Specifically, a ball-carrying cartridge type soluble ball seat includes a core rod 1 and a conical seat 3. The core rod 1 has a cross-shaped structure, with one end passing through the interior of the conical seat 3 in the vertical direction. The side wall of the core rod 1 near its bottom end has external threads, allowing for a detachable or threaded connection between the core rod 1 and the base 11, facilitating installation and disassembly. The other end connects to a sealing tool to apply pressure or torque when needed. The lower horizontal side of the core rod 1 has a chamfer, enabling easier contact with the upper surface of the conical seat 3, forming a tighter seal. The horizontal core rod 1 is a horizontal core rod, and the vertical core rod 1 is a vertical core rod.

[0027] like Figure 1As shown, the outer side of the cone seat 3 consists of a large outer cylinder, a truncated cone, and a small outer cylinder from left to right. In practical applications, the large outer cylinder faces upwards, and the small outer cylinder faces downwards. The diameter of the truncated cone decreases continuously from top to bottom, forming a smooth transition. The large end of the truncated cone is fixedly connected to the large outer cylinder, and the small end is fixedly connected to the small outer cylinder. The small outer cylinder reduces the space occupied by the cone seat 3 within the locking ring 10. It should be noted that the fixed connection here is welded, and the joint is smooth and burr-free. This not only improves the sliding or moving performance of the cone seat 3 but also avoids potential damage to the surrounding environment or equipment during use.

[0028] In addition to being fixedly connected, the large outer cylinder, the frustum of a cone, and the small outer cylinder can also be a single integrated structure.

[0029] A third groove is provided circumferentially on the side of the large outer cylinder away from the truncated cone. The third groove is used to fill the large ceramic column 8. It should be noted that the height of the large ceramic column located in the third groove must be greater than the width of the third groove.

[0030] The large ceramic column 8 is fixed on the side wall of the inner core 7 of the slip and mainly serves as an anchor. It is embedded in the inner wall of the sleeve to form a stable structure, ensuring that the inner core 7 of the slip and the base 11 can be firmly fixed in the appropriate position. The large ceramic column 8 is designed with a certain angle, which not only helps to better embed in the inner wall of the sleeve, but also provides stronger fixing force, thereby increasing the stability of the entire structure.

[0031] The cone seat 3 has a hollow structure with a large conical hole, a large inner circular hole, a small conical hole, and a small inner circular hole arranged from top to bottom. This structure not only meets the sealing and sliding requirements of the cone seat 3 but also ensures a tight fit with the core rod 1. The taper of the large conical hole matches the degree of the chamfer in the horizontal direction of the core rod 1, ensuring that when the core rod 1 is inserted into the cone seat 3, the chamfer of the horizontal core rod can form a tight fit with the large conical hole, thereby providing initial sealing and guiding functions.

[0032] The diameter of the large inner hole is the same as the diameter of the small end of the large conical hole, which avoids stress concentration and sealing problems that may be caused by a sudden change in diameter.

[0033] The diameter of the large end of the small conical hole is the same as the diameter of the large inner hole, which not only maintains the continuity of the internal structure of the cone seat 3, but also provides a tighter fit space for the core rod 1, especially the vertical core rod part.

[0034] The small end diameter of the conical hole is the same as the diameter of the small inner hole. In addition, the diameter of the small inner hole is matched with the diameter of the vertical core rod, ensuring that the core rod 1 can be inserted into the small inner hole.

[0035] A through hole is provided between the large outer cylinder and the large inner hole. The through hole is conical, with the smaller end facing the through hole and the larger end facing the core rod 1. The soluble ball 2 is installed in the through hole. The core rod 1 is detached from the cone seat 3. The soluble ball 2 lacks restraint and rolls along the slope of the through hole, entering the internal channel of the cone seat 3.

[0036] Soluble balls 2 typically serve to block specific channels or separate different layers. During multi-layer fracturing, soluble balls 2 are placed in the appropriate positions to prevent fracturing fluid from flowing to already fractured layers, ensuring that the fracturing fluid can accurately act on the target layer to create and propagate fractures, thereby improving oil extraction efficiency.

[0037] The cone seat 3 provides a suitable placement position for the soluble ball 2. The dissolution of the cone seat 3 can prevent it from remaining downhole for a long time and hindering subsequent production. No drilling or other treatments are required, which simplifies the subsequent downhole maintenance and production process.

[0038] The outer side of the truncated cone is fitted with a protective ring 4, a rubber sleeve 5, and a support ring 6. The rubber sleeve 5 is a combined cylindrical structure. As the locking rings inside the cone seat 3 and the base 11 continuously approach each other, the diameters of the protective ring 4, the rubber sleeve 5, and the support ring 6 continuously expand. When connected to the sleeve, they can provide stable support and guidance.

[0039] The support ring 6 is shaped like an inverted U-shape, with a chamfer at the connection point with the cone seat 3. The end of the support ring 6 that connects to the rubber sleeve 5 must be compatible with the rubber sleeve 5 to ensure a more reliable connection. When the cone seat 3 is connected to the locking ring 10 and locked, the diameters of the protective ring 4, rubber sleeve 5, and support ring 6 continuously increase. When the diameters of the rubber sleeve 5 and support ring 6 are the same as those of the sleeve, and under the action of the setting tool, the protective ring 4, rubber sleeve 5, and support ring 6 are tightly fitted to the inner wall of the sleeve, completing the seal. The lower end of the support ring 6 abuts against the upper end of the slip core 7.

[0040] The protective ring 4, the rubber sleeve 5, and the support ring 6 are tightly fitted to the casing through expansion to prevent displacement due to high-pressure fluid impact during fracturing, thus ensuring the sealing and safety of the fracturing operation.

[0041] The casing is used to protect the wellbore and serves as a carrier for the soluble ball seat, which is a ball-carrying sleeve. In the initial state, the casing is fitted over the outside of the cone seat 3 and the slip core 7, making it easy to install the base 11 into the designated position on the casing.

[0042] The inner core 7 of the slip is conical. When subjected to axial force, the conical inner core 7 expands or contracts radially, thereby better gripping or loosening the cone seat 3.

[0043] The Kawa inner core 7 can avoid the need for manual disassembly after the fracturing operation is completed.

[0044] It should be noted that the tilt angle of the truncated cone is the same as the tilt angle of the cone-shaped inner core 7, which facilitates advancement. When the setting tool applies axial force, because the sides of the truncated cone are tilted, the axial force can be decomposed into an effective advancing force of the base 11 and a radial expansion force. In scenarios where a tight fit with the sleeve is required, the radial expansion force allows the truncated cone to make better contact with the inner core 7 of the slip.

[0045] Specifically, after the inner core 7 of the slip is advanced to the designated position, the radial expansion force generated by the axial thrust allows the protective ring 4, the rubber sleeve 5, and the support ring 6 to better fit the sleeve, thereby achieving a better sealing effect. In addition, this disassembly method also allows the inner core 7 of the slip to push aside surrounding obstacles during the advancement process, whereas cylindrical shapes are easily blocked by obstacles.

[0046] The outer surface of the inner core 7 of the clasp has a first groove for mounting a large ceramic column. The inner core 7 of the clasp has bosses at both the top and bottom, with the bosses located on the side closest to the cone base 3. The boss at the top of the inner core 7 of the clasp abuts against the protruding part of the support ring 6, facilitating the connection between the support ring 6 and the inner core 7 of the clasp. The boss at the bottom of the inner core 7 of the clasp fits against the top of the base 11.

[0047] The base 11 is fitted at the bottom of the vertical core rod. The interior of the base 11 is also hollow. The locking ring 10 is fitted inside the base 11. The inner surface of the base 11 is machined with large threads and small threads. The large threads are used to connect with the locking ring 10, and the small threads are used to connect with the vertical core rod.

[0048] During fracturing operations, the soluble ball holder in a ball-carrying cartridge may be subjected to extremely high pressure and vibration, which could cause the connections between components to loosen or detach. To prevent this, a locking ring 10 is installed inside the base 11 and connected by threads, and is dissolved after fracturing is completed.

[0049] A second groove is provided circumferentially on the side wall of the base 11 facing the inner core 7 of the card. The small ceramic column is installed in the second groove. The installation of the small ceramic column in the second groove can improve electrical insulation, reduce mechanical friction, enhance structural stability, improve the performance indicators of the ball-carrying rubber tube type soluble ball seat, extend service life, and improve reliability.

[0050] After the base 11 is melted, there is no need to use traditional methods to destroy or remove the base 11, which improves the efficiency and economy of the entire production process.

[0051] In summary, firstly, the soluble ball 2 is placed inside the through hole of the core rod 1, ensuring that the side wall of the soluble ball 2 abuts against the through hole and the side wall of the core rod 1 to achieve stable placement. Then, the core rod 1 is passed through the cone seat 3, ensuring proper fit between the core rod 1 and the cone seat 3. Next, the lower end of the core rod 1 is passed through the locking ring 10, and the entire assembly is placed above the base 11. Finally, the lower end of the core rod 1 is fixed to the base 11 by a threaded connection, and the locking ring 10 is also connected to the base 11 by a large thread, forming a soluble ball seat of the ball-carrying rubber tube type for downhole stabilization tool structure.

[0052] Example 2 This invention discloses a method for setting a soluble ball seat using a ball-carrying rubber tube, comprising the following steps: In use, the setting tool pulls the upper end of the core rod 1, the lower end of the core rod 1 is connected to the base 11, the base 11 and the inner core 7 of the slip move upward, the diameter of the inner core 7 of the slip expands continuously, the bottom of the cone seat 3 is squeezed into the locking ring 10, the outer walls of the protective ring 4, the rubber tube 5 and the support ring 6 abut against the inner wall of the casing to complete the seal, the core rod 1 is pulled further, the core rod 1 and the base 11 move relative to each other and separate, the soluble ball 2 moves into the cone seat 3 under the drive of the fracturing fluid, seals the inner hole channel, and performs segmented fracturing, the soluble ball 2 automatically dissolves after the fracturing is completed.

[0053] The relative movement and separation of the core rod 1 and the base 11 include the mismatch in hardness between the core rod 1 and the base 11, the core rod 1 separating from the base 11 first under the action of the setting tool, and then being pulled out along the sleeve inlet direction.

[0054] Specifically: The setting tool is threaded to the upper end of the core rod 1. Under the action of the external force of the setting tool, the core rod 1 moves upward. Since the lower end of the core rod 1 is threaded to the base 11, the upper end of the base 11 is provided with a protective ring 4, a rubber sleeve 5, a support ring 6, and a slip inner core 7. The internal structure of the slip inner core 7 is conical, which abuts against the side wall of the conical seat 3. The large ceramic column 8 is fixed on the slip inner core 7, which plays an anchoring role. The slip inner core 7 expands outward until the large ceramic column 8 is embedded in the sleeve. The conical seat 3 penetrates deeper into the slip inner core 7 until the bottom of the conical seat 3 penetrates into the locking ring 10, completing the locking. During this period, the outer diameter of the rubber sleeve 5 and the support ring 6 expands outward. When the outer diameter of the rubber sleeve 5 and the support ring 6 expands to be the same as the inner diameter of the sleeve, under the action of the setting force provided by the setting tool, the protective ring 4, the rubber sleeve 5, and the support ring 6 are tightly attached to the inner wall of the sleeve, completing the seal.

[0055] The small ceramic column 9 is located on the side wall of the cone seat 3 and the base 11, which can reduce the friction between the cone seat 3 and the base 11 and the well wall during the well running process, thereby extending the service life of these components.

[0056] The setting tool continuously provides setting force. When the hardness of the bottom end of the core rod 1 does not match that of the base 11, it breaks. The core rod 1 moves upward along the direction of the setting tool. When the lower end of the core rod 1 is pulled out of the casing, fracturing fluid is added. The soluble ball 2, driven by the fracturing fluid, completes the sealing and falls into the internal channel of the cone seat 3, forming the sealing effect of segmented fracturing.

[0057] The fracturing process involves injecting fracturing fluid into the wellbore, gradually increasing the bottomhole pressure. When this pressure exceeds the tensile strength of the rock and the fracturing pressure caused by geostress, the rock fractures. These fractures extend perpendicular to the direction of minimum principal stress and continue to expand and extend with the continued injection of fracturing fluid. To keep the fractures open, proppant (such as silica sand or ceramsite) is added to the fracturing fluid. After fracturing is completed, the proppant remains in the fractures to prevent them from closing, thus creating highly conductive channels for oil and gas flow.

[0058] After fracturing, the soluble ball 2, cone seat 3, rubber sleeve 5, support ring 6, slip inner core 7, locking ring 10, and base 11 were dissolved. In summary, the cone seat 3 and slip inner core 7, combined with the protective ring 4, rubber sleeve 5, and support ring 6, sealed and secured the casing during the movement of the cone seat 3. The soluble ball 2, positioned within the through-hole, sealed the internal channels of the base under the action of the fracturing fluid flow, thus improving the reliability of the base and saving time and materials spent pumping the ball from the wellhead.

[0059] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", 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 the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0060] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

Claims

1. A soluble ball holder in the form of a ball-carrying rubber tube, characterized in that: The device includes a core rod (1), which passes through a cone seat (3), a collet core (7), a locking ring (10), and a base (11) from top to bottom. A through hole is provided on one side of the cone seat (3), and a soluble ball (2) is placed in the through hole and abuts against the core rod (1). A protective ring (4), a rubber tube (5), and a support ring (6) are sleeved on the outer wall of the cone seat (3). The lower end of the protective ring (5) abuts against the upper end of the rubber tube (5), the lower end of the rubber tube (5) abuts against the upper end of the support ring (6), and the lower end of the support ring (6) abuts against the upper end of the collet core (7). One end of the core rod (1) is engaged with the cone seat (3), and the other end is fixedly connected to the base (11).

2. The soluble ball holder of the ball-carrying rubber tube type according to claim 1, characterized in that: The protective ring (4), rubber tube (5), and support ring (6) are a combined cylindrical structure with a cylindrical outer surface and a conical hole inside. The diameter decreases continuously from top to bottom and abuts against the side wall of the conical seat (3).

3. The soluble ball holder of the ball-carrying rubber tube type according to claim 1, characterized in that: The cone seat (3) is composed of a large outer cylinder, a frustum of a cone and a small outer cylinder from top to bottom. The cone seat (3) has a hollow structure inside, consisting of a large conical hole, a large inner hole, a small conical hole and a small inner hole. The through hole is located inside the large outer cylinder and communicates with the large inner hole. The depth of the through hole is adapted to the thickness of the large outer hole.

4. The soluble ball holder of the ball-carrying rubber tube type according to claim 2, characterized in that: The inner core (7) of the slip is provided with a plurality of first grooves along the circumference, and the large ceramic column (8) is provided in the first groove for connection with the sleeve; The base (11) is provided with a second groove along the circumference, and the small ceramic column (9) is provided in the second groove for connection with the sleeve; The cone seat (3) has a third groove along the circumferential direction on the side away from the base (11), and the small ceramic column (9) is set in the third groove for connection with the sleeve.

5. The soluble ball holder of the ball-carrying rubber tube type according to claim 1, characterized in that: The inner core (7) of the card is provided with protrusions at both the upper and lower ends. The upper protrusion abuts against the support ring (6), and the lower protrusion abuts against the base (11). The upper protrusion and the lower protrusion are fixedly connected to the inner core (7).

6. The soluble ball holder of the ball-carrying rubber tube type according to claim 3, characterized in that: The outer surface of the small outer cylinder is provided with barbs for fixed connection with the locking ring (10).

7. The soluble ball holder of the ball-carrying rubber tube type according to claim 5, characterized in that: The base (11) is a cylindrical structure with large and small threads on its inner surface. The large thread is fixedly connected to the locking ring (10), and the small thread is fixedly connected to the core rod (1).

8. The soluble ball holder of the ball-carrying rubber tube type according to claim 1, characterized in that: The soluble ball (2), cone seat (3), protective ring (4), support ring (6), clasp core (7), locking ring (10) and base (11) are made of magnesium-based and aluminum-based soluble metal materials, and the rubber tube (5) is soluble rubber that automatically dissolves after cracking.

9. A method for setting a soluble ball seat in a ball-carrying tube type, characterized in that, Based on the ball-carrying tube type soluble ball holder as described in any one of claims 1-8 Includes the following steps: When in use, the setting tool pulls the upper end of the core rod (1), and the lower end of the core rod (1) is connected to the base (11). The base (11) and the inner core (7) of the slip move upward. The diameter of the inner core (7) of the slip expands continuously. The bottom of the cone seat (3) is squeezed into the lock ring (10). The outer walls of the protective ring (4), the rubber sleeve (5) and the support ring (6) abut against the inner wall of the casing to complete the seal. Continue to pull the core rod (1). The core rod (1) and the base (11) move relative to each other and separate. The soluble ball (2) moves into the cone seat (3) under the drive of the fracturing fluid, and seals the inner hole channel to carry out segmented fracturing. After the fracturing is completed, the soluble ball (2) automatically dissolves.

10. The method for setting and sealing a ball-carrying cartridge-type soluble ball seat according to claim 9, characterized in that: The relative movement and separation of the core rod (1) and the base (11) include the mismatch in hardness between the core rod (1) and the base (11), the core rod (1) being separated from the base (11) first under the action of the setting tool, and then being pulled out along the sleeve inlet direction.

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