A fully soluble bridge plug with a foldable blade seal with an outer diameter of 50mm and an expanded diameter of 114.3mm

Abstract

The present invention discloses a fully soluble bridge plug with a foldable blade seal having an outer diameter of 50 mm and an expanded diameter of 114.3 mm, comprising a tail seat, a slip group, a slip pusher, a blade support A, a blade support B, a blade, a blade pusher, a release hand, a slip hoop and a center rod. The tail seat is connected to the center rod by threads. The tail seat is connected to an independent five-petal slip through a double-headed threaded sleeve, and is fastened with a slip hoop before setting, and sits on the center rod. The slip pusher, the blade support A and the blade support B are connected to three blades respectively, which are folded and gathered together before setting. Through the downward movement of the blade pusher, the blade support A and the blade support B, each blade is squeezed and opened successively, and cooperates with each other on the same circumferential surface to form a complete arc surface to fit tightly to the casing wall to achieve a sealing effect. The slip pusher continues to descend and squeeze the slip group, so that the slip hoop breaks, and the slip rotates around the double-headed threaded sleeve at one end, so that the slip teeth at the other end quickly bite into the casing wall. The bridge plug of the present invention breaks the sealing mode of conventional bridge plugs and adopts a mechanical seal of a folded blade combination, which has a large diameter change range and can smoothly pass through when the casing of a fracturing operation is severely shrunken and deformed.

Description

Technical Field

[0001] The present invention relates to the technical field of downhole tools for petroleum, natural gas and shale gas fracturing operations, and in particular to a fully soluble bridge plug with a foldable blade seal having an outer diameter of 50 mm and an expanded diameter of 114.3 mm. Background Art

[0002] As the goal of oil and gas production shifts to low-permeability, low-grade resources, horizontal well staged fracturing technology has become an important means to effectively increase reservoir production and single well production, and bridge plugs are one of the important tools for fracturing operations and are increasingly widely used. Soluble bridge plugs can be used to temporarily plug oil, gas, and water layers, and are used in multi-layer fracturing of horizontal and vertical wells. Advanced degradable metal and rubber materials are used to achieve complete degradation of bridge plugs, helping users reduce the risk of use. Compared with traditional composite bridge plugs, there is no need for continuous tubing drilling plugs, reducing the cost of continuous tubing operations.

[0003] The soluble bridge plug is mainly composed of the bridge plug body, slips, sealing rubber tube, etc. In actual situations, due to the frequent occurrence of casing changes in deep unconventional gas blocks in the early stage, the minimum outer diameter of the bridge plug as the main tool is only 83 mm at home and abroad. When the casing is severely shrunken and deformed during or after horizontal well fracturing, the bridge plug cannot pass through the casing change position and cannot be pumped to the predetermined design position for effective segmented transformation, which limits the efficient development of deep unconventional gas. Summary of the invention

[0004] The purpose of the present invention is to design a fully soluble bridge plug with a foldable blade seal that has an outer diameter of 50 mm and an expanded diameter of 114.3 mm, so that it can pass smoothly when the casing of the fracturing operation is severely shrunken and deformed. When it reaches the pumping position, it is sealed by the folding combination of blades. After the fracturing construction is completed, the bridge plug can be completely dissolved and the full-diameter wellbore can be quickly put into production.

[0005] The technical solution of the patent of the present invention is: a fully soluble bridge plug with a foldable blade seal with an outer diameter of 50mm and an expanded diameter of 114.3mm, including a tail seat, a slip group, a slip push block, a blade support A, a blade support B, a blade, a blade push block, and also includes a release hand, a slip hoop and a center rod. The tail seat and the center rod are connected by threads, and the tail seat and the independent five-petal slip are connected by a double-headed threaded sleeve, and are fastened with a slip hoop before setting, and sit on the center rod. The slip group contains a plurality of slips, one end of the conical head of the slip push block cooperates with the slip bevel, and the other end is connected with three first blades by bolts, three second blades of blade support A, and three third blades of blade support B. The three groups of blades are in a folded and closed state before setting, and the contact parts of each blade are glued. The blade push block and the release hand are connected by threads, and the release hand is connected with a matching setting tool. As the anti-premature setting pin in the blade push block is cut off, the blade push block of the bridge plug moves downward. Through the extrusion of the blade push block, the bonding parts of the blades in contact are destroyed, and each group of blades is squeezed and opened. At the same time, the blade support A and the blade support B move downward until they match one end of the slip push block. At this time, each group of blades is fully opened, forming a complete arc surface that fits tightly with the casing. The setting force continues to be applied. Under the action of the blade push block, the slip push block squeezes the slip group, causing the slip hoop to break. The slip rotates around the double-threaded sleeve at one end, so that the slip teeth at the other end quickly engage with the casing wall. When it reaches the setting position, the spring pin in the blade push block bounces down into the limit groove reserved in the center rod to prevent the slip and blade from rebounding. In this process, the bridge plug expands from the initial outer diameter of 50mm to a large diameter close to the inner wall of the casing under the pumping and pushing action of the setting tool; after the fracturing construction is completed, the metal part of the bridge plug is completely dissolved.

[0006] The semicircular grooves on the center rod cooperate with the semicircular bosses of the blade push block, blade support A, blade support B and slip push block to limit the circumferential rotation of the blade. Three limit grooves are evenly distributed circumferentially in the middle of the center rod. When the bridge plug is set, the spring pin in the blade push block bounces into the limit groove to prevent the slip and blade from rebounding, so that the bridge plug always maintains an anchored sealing state during the fracturing process.

[0007] The slip group is a split-petal single slip group structure. Since the outer diameter of the bridge plug is 50 mm, the slips are distributed in five axial directions. The slips are relatively long and are connected to the tail seat respectively through double-headed threaded sleeves. Before sealing, the five-petal slips are fixed to the center rod by the slip hoop. When the slip push block moves downward, the slip hoop is squeezed and broken. The slip group then opens under the squeezing action of the cone head of the slip push block and quickly engages with the casing wall to complete the anchoring. The carrier of the slip group is composed of aluminum-based soluble alloy material, and slip teeth with different tooth heights are distributed at one end, so that the slip teeth are evenly stressed when anchoring. The slip teeth are designed as a lamellar tooth structure made of ceramic material, which can improve the reliability of slip anchoring and facilitate backflow.

[0008] The cava push block, blade support A and blade support B are all made of aluminum-based soluble alloy materials. The cava push block is relatively long to avoid interference between the cava and the blade during sealing. One end of the cava push block is a cone, which cooperates with the closed cava group before sealing. The other end is connected to three blades with bolts. Both ends of the blade support A are conical surfaces, so that the blades connected to the cava push block open under the push of the sealing force. The blade support A and the blade support B are respectively connected to the three blades in a circumferentially staggered manner. Under the push of the sealing force, the blades connected to each part gradually open, and the blade support A and the blade support B move downward until they are in contact with the cava push block. Each blade is on the same circumferential surface, which plays a sealing role as a bridge plug.

[0009] There are nine blades in total, which are connected to the cava push block, blade support A and blade support B in groups of three. The top ends of the blades are chamfered to ensure that the overall size of the bridge plug is 50mm before sealing, and to facilitate gluing after the blades are folded. During sealing, the residual glue will not affect the close fit of the blades, thereby ensuring the reliability of the seal. The blades are arc-shaped and thicker in the middle, so that the blades have better deformation resistance and pressure bearing capacity during fracturing construction, and can better ensure the sealing performance of the bridge plug.

[0010] The blade push block has three inclined bosses evenly distributed circumferentially at one end, which cooperate with the blade connected to the blade support B before sealing. An anti-early sealing pin and three circumferentially evenly distributed limit spring pins are provided in the middle. When the bridge plug is pumped to the specified position, the anti-early sealing pin is sheared off and the blade push block moves downward. After the blade push block reaches the sealing completion position, the internal spring pin bounces into the limit groove reserved in the center rod to prevent the blade from rebounding. The other end is connected to the release mechanism with a thread.

[0011] The release mechanism is threadedly connected to the blade push block at one end and fixedly connected to the sealing tool via a pin at the other end. The release mechanism can push the blade push block to move on the center rod. When the bridge plug is sealed, the sealing tool is retracted, the fixing pin is cut off, and the tool is separated from the bridge plug, thereby ensuring that the bridge plug can be lowered and released.

[0012] The beneficial effects of the present invention are:

[0013] 1) The outer diameter of the soluble bridge plug of the present invention is 50 mm, which is smaller than that of the existing soluble bridge plug. There is no need to consider the insertion of continuous oil pipes, and it can be adapted to the smallest existing perforating gun for fracturing construction, which can effectively solve the technical problem of severe shrinkage and deformation of the casing in fracturing operations and the lack of available separation tools.

[0014] 2) The sealing structure designed in the present invention is a mechanical seal, which breaks the conventional sealing method of soluble bridge plug extrusion rubber cylinder or metal. The folding method of the blades is used to achieve the initial outer diameter of the bridge plug of 50mm, which is expanded to a large diameter of 114.3mm, and the sealing is stable and the pressure bearing is reliable.

[0015] 3) The slip group designed in the present invention is a split-flap single slip group structure. Since the outer diameter of the bridge plug is 50 mm, there are 5 slips distributed in the axial direction, the slips are relatively long, and are fixedly connected to the tailstock through a double-threaded sleeve. When the slip push block moves downward to a limit position, the slip group can rotate a certain angle to move radially outward, and quickly engage with the casing wall to complete the sealing. The carrier of the slip group is composed of aluminum-based soluble alloy material, and the slip teeth are designed as a sheet-like tooth structure with different heights. They are made of ceramic material, which can reduce the engagement depth and reduce the damage to the casing, so that the slips are evenly stressed when anchored, which can improve the reliability of slip anchoring and facilitate backflow.

[0016] 4) The soluble bridge plug of the present invention does not need to be sealed by inserting a sealing ball into the seat. The bridge plug can directly and quickly achieve the sealing and separation function to carry out staged fracturing construction. Compared with the composite bridge plug, there is no need for drilling and plugging operations, which saves the time and cost of drilling and grinding the bridge plug, is easy to flow back, and the full-bore wellbore can be quickly put into production after dissolution is completed. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be described by way of drawings, in which:

[0018] Figure 1 It is a schematic diagram of the overall structure of a fully soluble bridge plug with a foldable blade seal having an outer diameter of 50 mm and an expanded diameter of 114.3 mm according to the present invention.

[0019] Figure 2 This is a cross-sectional view of the overall structure of a fully soluble bridge plug with a foldable blade seal having an outer diameter of 50 mm and an expanded diameter of 114.3 mm according to the present invention.

[0020] Figure 3 It is a structural schematic diagram of a fully soluble bridge plug sealed with folding blades having an outer diameter of 50 mm and an expanded diameter of 114.3 mm after being set.

[0021] Figure 4 yes Figure 1 Schematic diagram of the structure of the mid-folding blade seal.

[0022] In the figure, 1-center rod, 2-tail stock, 21-double-headed threaded sleeve, 3-cava group, 31-cava hoop, 4-cava push block, 41-first blade, 5-blade support A, 51-second blade, 6-blade support B, 61-third blade, 7-blade push block, 71-spring pin, 72-anti-early setting pin, 8-release hand, 11-limiting groove, 12-pin groove. DETAILED DESCRIPTION

[0023] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0024] like Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown, a fully soluble bridge plug with a foldable blade seal having an outer diameter of 50 mm and an expanded diameter of 114.3 mm according to the present invention comprises a tail seat 2, a slip group 3, a slip push block 4, a blade support A5, a blade support B6, a blade push block 7, and also comprises a release hand 8, a slip hoop 31 and a center rod 1. The tail seat 2 is connected to the center rod 1 by threads, and the tail seat 2 is connected to an independent five-petal slip by a double-headed threaded sleeve 21, and is fastened with a slip hoop 31 before setting, and is seated on the center rod. One end of the conical head of the slip push block 4 cooperates with the slip inclined surface, and the other end is connected to the three first blades 41 by bolts. The blade support A5 connects the three second blades 51, and the blade support B6 connects the three third blades 61. The three groups of blades are in a closed state before setting, and the contact parts of the blades are glued. The blade push block 7 is connected to the release hand 8 by threads, and the release hand 8 is connected to a matching setting tool. As the anti-premature sealing pin 72 in the blade push block 7 is cut off, the blade push block 7 of the bridge plug moves downward. Through the extrusion of the blade push block 7, the adhesive parts of the blades in contact are destroyed, and the first blade 41, the second blade 51, and the third blade 61 are squeezed and opened. At the same time, the blade support A5 and the blade support B6 move downward until they are matched with one end of the cava push block 4. At this time, each group of blades is fully opened to form a complete arc surface that fits tightly with the casing. The sealing force continues to be applied. Under the action of the blade push block 7, the cava push block 4 squeezes the cava group 3, so that the cava hoop 31 breaks, and the cava 3 rotates around the double-headed threaded sleeve 21 at one end, so that the cava teeth at the other end quickly engage with the casing wall. When the sealing position is reached, the spring pin 71 in the blade push block 7 bounces down into the limiting groove 11 reserved in the center rod 1 to prevent the cava 3, the first blade 41, the second blade 51, and the third blade 61 from rebounding. During this process, the bridge plug expands from an initial outer diameter of 50 mm to a large diameter close to the inner wall of the casing under the pumping action of the setting tool; after the fracturing construction is completed, the metal part of the bridge plug is completely dissolved.

[0025] The working principle of the fully soluble bridge plug with foldable blade seal of the present invention, which has an outer diameter of 50 mm and an expanded diameter of 114.3 mm, is as follows: when in use, the bridge plug is connected to the sealing tool through the release mechanism 8, the bridge plug is pumped to a predetermined position by a cable, the gunpowder is ignited by the cable to generate high-pressure gas to fill the combustion chamber, and the high-pressure gas in the sealing tool of the sealing push cylinder pushes the blade push block 7, so that the blade push block 7 of the bridge plug moves downward, and the contact adhesive parts of the first blade 41, the second blade 51, and the third blade 61 are destroyed by the extrusion of the blade push block 7, and each group of blades is squeezed and opened successively, and at the same time, the blade support A5 and the blade support B6 move downward Until it matches with one end of the cava push block 4, at this time the first blade 41, the second blade 51, and the third blade 61 are fully opened, matching each other and forming a complete arc surface that fits tightly with the casing, and the sealing force continues to be applied. Under the action of the blade push block 7, the cava push block 4 squeezes the cava group 3, causing the cava hoop 31 to break, and the cava 3 rotates around the double-headed threaded sleeve 21 at one end, so that the cava teeth at the other end quickly engage with the casing wall. When it reaches the sealing position, the spring pin 71 in the blade push block 7 bounces down into the limiting groove 11 reserved in the center rod 1 to prevent the cava 3, the first blade 41, the second blade 51, and the third blade 61 from rebounding. In this process, the bridge plug expands from the initial outer diameter of 50mm to a large diameter that is close to the inner wall of the casing under the pumping action of the sealing tool.

[0026] The soluble bridge plug does not need to be cast into the seat to achieve contact sealing, and the bridge plug can directly and quickly achieve separation. The soluble metal part of the bridge plug and the sealing rubber tube 9 will be completely dissolved, and then the wellbore will be fully opened.

[0027] Example:

[0028] like Figure 1 , Figure 2As shown, a fully soluble bridge plug with a foldable blade seal having an outer diameter of 50 mm and an expanded diameter of 114.3 mm according to the present invention comprises a tail seat 2, a slip group 3, a slip push block 4, a blade support A5, a blade support B6, a blade push block 7, and also comprises a release hand 8, a slip hoop 31 and a center rod 1. The tail seat 2 is connected to the center rod 1 by threads, and the tail seat 1 is connected to an independent five-petal slip by a double-head threaded sleeve 21, and is fastened with a slip hoop 31 before setting, and is seated on the center rod. One end of the conical head of the slip push block 4 cooperates with the inclined surface of the slip 3, and the other end is connected to the three first blades 41 by bolts. The blade support A5 and the blade support B6 are also connected to the three second blades 51 and the three third blades 61 respectively. The three groups of blades are in a closed state before setting, and the inclined surface parts of the blades that contact each other are glued. The blade push block 7 is connected to the release hand 8 by threads, and the release hand 8 is connected to the matching setting tool. As the anti-premature sealing pin 72 in the blade push block 7 is cut off, the blade push block 7 of the bridge plug moves downward. Through the extrusion of the blade push block 7, the adhesive parts of the blades in contact are destroyed, and each group of blades is squeezed and opened. At the same time, the blade support A5 and the blade support B6 move downward until they are matched with one end of the cava push block 4. At this time, each group of blades is fully opened and fits tightly with the casing. The sealing force continues to be applied. Under the action of the blade push block 7, the cava push block squeezes the cava group, so that the cava hoop 31 breaks, and the cava 3 rotates around the double-headed threaded sleeve at one end, so that the cava teeth at the other end quickly engage with the casing wall. When reaching the sealing position, the spring pin 71 in the blade push block 7 bounces down into the limiting groove 11 reserved in the center rod 1 to prevent the cava 3, the first blade 41, the second blade 51, and the third blade 61 from rebounding. During this process, the bridge plug is deformed and expanded from the initial outer diameter of 50mm to the inner wall of the casing under the pumping action of the setting tool, meeting the pressure requirements while also having a good sealing effect. After the construction is completed, the bridge plug can be completely dissolved and the full-bore wellbore can be quickly put into production.

[0029] like Figure 3As shown, after the bridge plug is set, the first blade 41, the second blade 51, and the third blade 61 fit together tightly, and the top end fits with the casing to achieve sealing conditions, and the blade push block 7 and the blade support B6 are provided with conical bosses, which play the role of pushing the first blade 41, the second blade 51, and the third blade 61 to open when setting. After setting, the inclined surfaces of each boss fit closely with the roots of the first blade 41, the second blade 51, and the third blade 61, reducing the bending moment of the first blade 41, the second blade 51, and the third blade 61 when bearing pressure, making the pressure bearing performance more reliable. The slip group 3 is a split-petal single slip group structure with a long length and a total of 5 slips distributed along the axial direction. One end of the slip is distributed with sheet-like toothed slip teeth of different heights. One end of the slip group 3 is provided with a groove, and a slip hoop 31 is installed in the groove to fix the slip group 3 to prevent separation. When sealing, the slip ring 31 is squeezed and breaks and falls off. Since the slip ring 31 is located behind the slip tooth, the breakage will not affect the anchoring of the slip 3. One end of the slip group 3 rotates around the double-headed threaded sleeve and opens. The five-petal slips evenly bite into the casing wall, so that the slip group 3 is subjected to more uniform force when anchoring, avoiding stress concentration and making the anchoring effect more reliable.

[0030] like Figure 4 As shown, the sealing structure is that the first blade 41, the second blade 51, and the third blade 61 are respectively installed on the slip push block 4, the blade support A5 and the blade support B6. The blades are designed to be arc-shaped and thicker in the middle, so that the blades have better anti-deformation and pressure-bearing capacity during the fracturing construction process, and can better ensure the sealing performance of the bridge plug. Before setting, each group of blades is folded, and the inclined surfaces at the two ends of the top are in contact and glued. When setting, the blade push block 7 squeezes and destroys the glued part. Since the inclined surfaces at the two ends are located at the blade The damaged residual glue will not affect the fitting of the left and right sides of the blade. The first blade 41, the second blade 51, and the third blade 61 are opened one after another. The blade support A5 and the blade support B6 move downward to one end of the cava push block, so that the first blade 41, the second blade 51, and the third blade 61 are matched on the same circumferential surface. The edge of the end of the cava push block 4 that contacts the blade is an arc surface, which is the same as the arc surface after the blades are combined. The two fit tightly, making up for the sealing defect caused by the gap fit between the blade supports 5 and 6.

[0031] The most ingenious part of this technology is that the outer diameter of the soluble bridge plug is 50mm, which can smoothly pass through when the casing of the fracturing operation is severely shrunken and deformed, without considering the insertion of continuous oil pipes, and can be adapted to the smallest existing perforating gun for fracturing operations. The sealing structure is a mechanical seal, which breaks the conventional sealing method of squeezing rubber tubes or metals for soluble bridge plugs. The initial outer diameter of the bridge plug is 50mm, which is expanded to a large diameter of 114.3mm by folding the blades. Through the ingenious cooperation of the cava push block and the various supports and the limit design at both ends, the bridge plug has a reliable sealing effect and pressure bearing capacity. During the sealing process of the bridge plug, there is no need to put the sealing ball into the seat for sealing. The sealing and separation effect can be directly and quickly realized, and there is no need for drilling and plugging operations, which saves the time and cost of drilling and grinding the bridge plug, and is easy to return. After the dissolution is completed, the full-bore wellbore can be quickly put into production.

[0032] In the description of the present invention, it is necessary to understand that if there are terms such as up, down, left, right, inside, outside, radial, etc. indicating orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings, rather than indicating or implying that the device or element referred to must have a characteristic orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as a limitation on this patent.

[0033] The above-mentioned embodiments only express the specific implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the protection scope of the present application. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the technical solution concept of the present application, and these all belong to the protection scope of the present application.

Claims

1. A fully soluble bridge plug with a foldable blade seal having an outer diameter of 50 mm and an expanded diameter of 114.3 mm, comprising a tail seat (2), a slip group (3), a slip push block (4), a blade support A (5), a blade support B (6), a blade push block (7), a release handle (8), a slip hoop (31) and a center rod (1); the tail seat (2) and the center rod (1) are connected by threads, the tail seat (2) and an independent five-petal slip are connected by a double-headed threaded sleeve (21), and are fastened by a slip hoop (31) before setting, and are seated on the center rod; the slip group (3) comprises a plurality of The invention relates to a slip block (4), wherein one end of the conical head of the slip block (4) cooperates with the inclined surface of the slip block, and the other end is connected to the three first blades (41) by bolts; the blade support A (5) is connected to the three second blades (51), and the blade support B (6) is connected to the three third blades (61); the first blade (41), the second blade (51) and the third blade (61) are in a closed state before setting, and the contacting parts of the blades are glued; the blade push block (7) is connected to the release hand (8) by threads, and the release hand (8) is connected to a matching setting tool; as the anti-premature setting pin in the blade push block (7) is screwed, the blade push block (7) is screwed to the release hand (8), and the release hand (8) is connected to a matching setting tool; as the anti-premature setting pin in the blade push block (7) is screwed, the blade push block (7) is screwed to the release hand (8), and the release hand (8) is screwed to the ... (72) is sheared off, so that the blade push block (7) of the bridge plug moves downward. Through the extrusion of the blade push block (7), the adhesive parts of the blades in contact are destroyed, and the first blade (41), the second blade (51) and the third blade (61) are squeezed and opened. At the same time, the blade support A (5) and the blade support B (6) move downward until they are matched with one end of the slip push block (4). At this time, each group of blades is completely opened to form a complete arc surface that fits tightly with the casing. The sealing force is continuously applied. Under the action of the blade push block (7), the slip push block (4) squeezes the slip group (3), so that the slip hoop (3 1) fracture, one end of the slip (3) rotates around the double-threaded sleeve (21), so that the slip teeth at the other end of the slip quickly bite into the casing wall, and when the sealing position is reached, the spring pin (71) in the blade push block (7) bounces down into the limit groove (11) reserved in the center rod (1), preventing the slip (3), the first blade (41), the second blade (51) and the third blade (61) from rebounding; in this process, the bridge plug expands from the initial outer diameter of 50 mm to a large diameter close to the inner wall of the casing under the pumping action of the sealing tool; after the fracturing construction is completed, the metal part of the bridge plug is completely dissolved; The slip push block (4), the blade support A (5) and the blade support B (6) are all made of aluminum-based soluble alloy material. The slip push block (4) is relatively long to prevent the slip (3) from interfering with the first blade (41), the second blade (51) and the third blade (61) during setting. One end of the slip push block (4) is a cone, which cooperates with the closed slip group (3) before setting. The other end is connected to the three first blades (41) by bolts. Both ends of the blade support A (5) are conical surfaces. , so that the first blade (41) connected to the cava push block (4) is opened under the push of the sealing force, and the blade support A (5) and the blade support B (6) are respectively connected to the three second blades (51) and the three third blades (61) in a circumferentially staggered manner. Under the push of the sealing force, the blades connected in each part gradually open, and the blade support A (5) and the blade support B (6) move downward until they are in contact with the cava push block (4). The blades are on the same circumferential surface, which plays a sealing role as a bridge plug.

2. A fully soluble bridge plug with foldable blade seal having an outer diameter of 50 mm and an expanded diameter of 114.3 mm according to claim 1, characterized in that: Both ends of the top of the first blade (41), the second blade (51), and the third blade (61) are chamfered to ensure that the overall size of the bridge plug before sealing is 50 mm, and to facilitate the gluing of the first blade (41), the second blade (51), and the third blade (61) after folding. In addition, when sealing, the residual glue will not affect the tight fit of the first blade (41), the second blade (51), and the third blade (61), thereby ensuring the reliability of the seal. The first blade (41), the second blade (51), and the third blade (61) are arc-shaped and thicker in the middle, so that the first blade (41), the second blade (51), and the third blade (61) have better anti-deformation ability and pressure bearing capacity during the fracturing construction process, and can better ensure the sealing performance of the bridge plug.

3. A fully soluble bridge plug with foldable blade seal having an outer diameter of 50 mm and an expanded diameter of 114.3 mm according to claim 1, characterized in that: One end of the blade push block (7) is evenly provided with three inclined bosses in the circumferential direction, which cooperate with the third blade (61) connected to the blade support B (6) before setting. The middle part is provided with an anti-early setting pin (72) and three circumferentially evenly distributed limiting spring pins (71). When the bridge plug is pumped to the specified position, the anti-early setting pin (72) is cut off, and the blade push block (7) moves downward. After the blade push block (7) reaches the setting completion position, the internal spring pin (71) rebounds into the limiting groove (11) reserved in the center rod to prevent the first blade (41), the second blade (51) and the third blade (61) from rebounding. The other end of the blade push block (7) is threadedly connected to the release handle (8).

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