Perforator based on cable-free connection and perforation method

Abstract

The invention provides a perforator based on cable-free connection and a perforation method. The perforator sequentially comprises a data return part, an electromagnetic speed reduction part, a detonation disconnection part and a perforation gun from top to bottom in the depth of a shaft. Wherein the data return part is used for collecting underground perforation operation data, and the data return part at least comprises a power part which is used for providing power for the perforator to return to the ground after perforation operation; the electromagnetic speed reduction part is used for controlling the magnetic force of the casing to the perforator and adjusting the position of the perforator in the horizontal well section; the detonating disconnecting part is used for detonating after perforating operation is completed so as to disconnect the detonating disconnecting part and the perforating gun. The perforating gun is used for enabling perforating bullets in the perforating gun to be ejected into the stratum. According to the perforator and the perforation method, perforation is conducted in a cable-free mode, conventional cable connection or coiled tubing conveying type underground perforation well completion operation can be replaced, and the perforator and the perforation method have the advantages of being low in operation cost and high in well completion efficiency.

Description

Technical Field

[0001] The present invention relates to the field of oil development, especially the technical field of oil perforating completion, and specifically relates to a perforator and a perforating method based on cableless connection. Background Art

[0002] During the entire process of oil development, perforating technology is an important part of completion engineering. In traditional perforating operations, cables or coiled tubing are often used for manual operation of downhole tools, which is time-consuming, has low operation efficiency, and high operation cost. For example, in the prior art, cable connection or coiled tubing conveyance downhole technology is usually adopted. In this way, the control of the downhole rate is very important. At present, the main method is to optimize the cable material and improve the cable fracture strength to increase the downhole rate of the tool, but the downhole speed still cannot be effectively controlled, and the problems of numerous required surface equipment, low equipment utilization rate, cumbersome and time-consuming operation, high operation cost, and inability to perform continuous fracturing operations still remain.

[0003] In summary, there is an urgent need for a more efficient perforating technology in the prior art, which has important practical value for the exploitation of oil and gas fields. Summary of the Invention

[0004] The perforator and the perforating method based on cableless connection provided by the embodiments of the present invention innovatively perform perforating operations in a cableless manner, and adopt a modular design for each component to cooperate with different specifications of perforating guns, which can be applied to different oil and gas wells, replacing the conventional downhole perforating completion operations with cable connection or coiled tubing conveyance. It has the advantages of low operation cost and high completion efficiency, and solves the problems of cumbersome and time-consuming operation, high operation cost, and inability to perform continuous fracturing operations in traditional perforating technology.

[0005] On the one hand, the embodiments of the present invention provide a perforator based on cableless connection, which successively includes from top to bottom in the wellbore depth: a data return part, an electromagnetic deceleration part, a detonation disconnection part, and a perforating gun; wherein:

[0006] The data return part is used to collect the perforating operation data downhole, and the data return part at least includes a power part, which is used for the power of the perforator to return to the ground after the perforating operation;

[0007] The electromagnetic deceleration part is used to control the magnetic force of the casing on the perforator and adjust the position of the perforator in the horizontal well section;

[0008] The detonation disconnection part is used to perform detonation after the perforating operation to disconnect the detonation disconnection part and the perforating gun;

[0009] The perforating gun is used to shoot the perforating charges inside it into the formation.

[0010] In some embodiments of the present invention, the power unit includes a propeller, a motor, a gyroscope, and a battery;

[0011] The detonation disconnecting unit further includes: a magnetic positioning unit for performing a primary positioning of the perforating tool in the wellbore;

[0012] The power unit is further configured to perform a secondary positioning of the perforating tool through the gyroscope after the primary positioning.

[0013] In some embodiments of the present invention, the battery includes at least two parts, and at least one part of the battery is disposed below the detonation disconnecting unit.

[0014] In some embodiments of the present invention, the cableless-connected perforating tool further includes:

[0015] A fishing head disposed on the upper part of the data return unit for fishing the perforating tool;

[0016] A buoyancy chamber disposed on the upper part of the electromagnetic deceleration unit for reducing the descending speed of the perforating tool in the wellbore and providing power for the perforating tool to return to the ground.

[0017] In some embodiments of the present invention, the perforating gun includes: a perforating gun body and a bridge plug setting unit, wherein:

[0018] The bridge plug setting unit is disposed at the lower part of the perforating gun body for setting the bridge plug on the formation;

[0019] The perforating gun body and the bridge plug setting unit are made of a soluble alloy material.

[0020] In some embodiments of the present invention, the bridge plug setting unit includes:

[0021] A gunpowder chamber: disposed at the bottom of the perforating gun for providing setting power and having a first pin disposed therein;

[0022] A releasing joint disposed below the gunpowder chamber and having a second pin disposed therein, and the shear force for the first pin to break is less than the shear force for the second pin to break;

[0023] A pushing cylinder sleeved outside the gunpowder chamber and the releasing joint;

[0024] A rubber cylinder disposed below the pushing cylinder for plugging the wellbore;

[0025] A fixing cone disposed below the rubber cylinder for cooperating with the pushing cylinder to squeeze the rubber cylinder, and the end of the fixing cone facing the bottom of the well is conical;

[0026] A slip sleeved on the conical part of the fixing cone for plugging the wellbore.

[0027] In some embodiments of the present invention, the bridge plug setting portion further includes:

[0028] Elastic claws are arranged inside the rubber cylinder, and the end facing the bottom of the well is a claw structure, and the claw structure is used to cooperate with the card slot of the fixed cone to fix the rubber cylinder after setting.

[0029] On the other hand, an embodiment of the present invention provides a method for perforating using the above-mentioned cable-free connection perforator, and the method includes:

[0030] The magnetic positioning part and the gyroscope of the perforator position the perforator according to the pre-acquired wellbore structure data, so that the current depth of the perforator is a preset perforation depth;

[0031] The perforating gun of the perforator perforates the layer corresponding to the perforation depth;

[0032] The detonation disconnection part of the perforator reduces the weight of the perforator;

[0033] The power part on the perforator provides thrust to make the perforator return to the ground, wherein the perforator stores the perforation operation data collected underground.

[0034] In some embodiments of the present invention, the magnetic positioning part and the gyroscope of the perforator position the perforator according to the pre-acquired wellbore structure data, so that the current depth of the perforator is a preset perforation depth, including:

[0035] Performing a primary positioning on the perforator according to the wellbore structure data and the magnetic positioning part of the perforator;

[0036] The magnetic positioning part of the perforator performs a primary positioning on the perforator according to the wellbore structure data;

[0037] The gyroscope determines the current descending speed of the perforator;

[0038] The magnetic positioning part performs a secondary positioning on the perforator according to the current descending speed, so that the current depth is the perforation depth.

[0039] In some embodiments of the present invention, the detonation disconnection part of the perforator reduces the weight of the perforator, including:

[0040] The detonation disconnection part detonates the pyrotechnic release in it and makes it break, so that the detonation disconnection part and the components below it are separated from the perforator.

[0041] In some embodiments of the present invention, before the magnetic positioning part and the gyroscope of the perforating tool position the perforating tool according to the pre-acquired wellbore structure data so that the current depth of the perforating tool is the preset perforating depth, the following steps are further included:

[0042] The power part and the buoyancy chamber of the perforating tool control the descending speed of the perforating tool in the wellbore;

[0043] After the detonating disconnecting part of the perforating tool reduces the weight of the perforating tool, the following steps are further included:

[0044] The buoyancy chamber provides buoyancy to enable the perforating tool to return to the ground.

[0045] In some embodiments of the present invention, before the perforating gun of the perforating tool perforates the formation corresponding to the perforating depth, the following steps are further included:

[0046] The electromagnetic deceleration part of the perforating tool controls the magnetic force between the perforating tool and the casing so that the perforating tool is located on the central axis of the casing;

[0047] After the perforating gun of the perforating tool perforates the formation corresponding to the perforating depth, the following steps are further included:

[0048] The electromagnetic deceleration part eliminates the magnetic force.

[0049] In some embodiments of the present invention, the perforating tool includes at least two electromagnetic deceleration parts, which are respectively located at the top and the top of the perforating tool; the perforating method further includes:

[0050] When the perforating interval is a horizontal well section, the two electromagnetic deceleration parts adjust the magnetic force received by the perforating tool in the casing so that the perforating tool is located on the central axis of the casing.

[0051] In some embodiments of the present invention, before the perforating gun of the perforating tool perforates the formation corresponding to the perforating depth, the following steps are further included:

[0052] The bridge plug setting part at the bottom of the perforating tool sets the bridge plug in the wellbore.

[0053] In some embodiments of the present invention, the bridge plug setting part at the bottom of the perforating tool setting the bridge plug in the wellbore includes:

[0054] The bridge plug setting ignites the gunpowder inside the gunpowder chamber, causing the first pin inside the gunpowder chamber to break, and generating a thrust to push the push tube towards the fixed cone direction, so as to squeeze the rubber cylinder between the push tube and the fixed cone, causing the rubber cylinder to set the bridge plug in the wellbore;

[0055] One end of the fixed cone with a conical shape enters into the slips through the thrust, so as to set the slips in the wellbore;

[0056] The second pin inside the release mechanism at the lower part of the powder chamber breaks due to the thrust, so that the bridge plug setting is disengaged from the perforator. Among them, the shearing force for the breakage of the first pin is less than the shearing force for the breakage of the second pin.

[0057] In some embodiments of the present invention, for the bridge plug setting part at the bottom of the perforator to set the wellbore, it further includes:

[0058] The elastic claws inside the rubber cylinder are clamped on the card slots of the fixed cone by the thrust to fix the rubber cylinder after setting. Among them, the perforating gun and the bridge plug setting part are made of a soluble alloy material.

[0059] Thirdly, the embodiments of the present invention provide a perforation system based on a cableless-connected perforator, and the system includes:

[0060] A depth positioning module, configured to position the perforator according to pre-acquired wellbore structure data, the magnetic positioning part of the perforator, and a gyroscope, so that the current depth of the perforator is a preset perforation depth;

[0061] A layer perforation module, configured to perforate the layer corresponding to the perforation depth through the perforating gun of the perforator;

[0062] A weight reduction module, configured to reduce the weight of the perforator through the detonation disconnect part of the perforator;

[0063] A perforator return first module, configured to use the thrust provided by the power part on the perforator to return the perforator to the ground, where the perforator stores the perforation operation data collected underground.

[0064] In some embodiments of the present invention, the depth positioning module includes:

[0065] A primary positioning unit, configured to perform primary positioning on the perforator according to the wellbore structure data and the magnetic positioning part of the perforator;

[0066] A download speed determination unit, configured to determine the current descending speed of the perforator according to the gyroscope;

[0067] A secondary positioning unit, configured to perform secondary positioning on the perforator according to the current descending speed, so that the current depth is the perforation depth.

[0068] In some embodiments of the present invention, the weight reduction module includes:

[0069] A weight reduction unit, configured to detonate the pyrotechnic release inside the detonation disconnect part and cause it to break, so that the detonation disconnect part and the components below it are disengaged from the perforator.

[0070] In some embodiments of the present invention, the perforating system based on a cableless-connected perforator further includes:

[0071] A descending speed control module, configured to control the descending speed of the perforator in the wellbore through the power unit and the buoyancy chamber of the perforator;

[0072] A perforator return second module, configured to enable the perforator to return to the ground through the buoyancy provided by the buoyancy chamber.

[0073] In some embodiments of the present invention, the perforating system based on a cableless-connected perforator further includes:

[0074] A position adjustment module, configured to control the magnetic force between the perforator and the casing through the electromagnetic deceleration part of the perforator, so that the perforator is located on the central axis of the casing;

[0075] A magnetic force elimination module, configured to eliminate the magnetic force through the electromagnetic deceleration part.

[0076] In some embodiments of the present invention, in the perforating system based on a cableless-connected perforator, the perforator includes at least two electromagnetic deceleration parts, which are respectively located at the top and the top of the perforator; the perforating system based on a cableless-connected perforator further includes:

[0077] A magnetic force adjustment module, configured to, when the perforating interval is a horizontal well interval, adjust the magnetic force received by the perforator in the casing through the two electromagnetic deceleration parts, so that the perforator is located on the central axis of the casing.

[0078] In some embodiments of the present invention, the perforating system based on a cableless-connected perforator further includes:

[0079] A wellbore setting module, configured to set the wellbore through the bridge plug setting part at the bottom of the perforator.

[0080] In some embodiments of the present invention, the wellbore setting module includes:

[0081] A primary setting unit, configured to, by igniting the gunpowder inside the gunpowder chamber of the bridge plug setting, break the first pin inside the gunpowder chamber and generate a thrust to push the push cylinder towards the fixed cone direction, so as to squeeze the rubber cylinder between the push cylinder and the fixed cone, and make the rubber cylinder set the wellbore;

[0082] A secondary setting unit, configured to, through the thrust, enable the tapered end of the fixed cone to enter into the inside of the slips, so as to make the slips set the wellbore;

[0083] The bridge plug release unit is used to break the second pin in the release sleeve at the lower part of the powder chamber through the thrust, so that the bridge plug is set and separated from the perforator. Among them, the shearing force for breaking the first pin is less than the shearing force for breaking the second pin.

[0084] In some embodiments of the present invention, the wellbore setting module further includes:

[0085] The rubber cylinder fixing unit is used to make the elastic claws inside the rubber cylinder catch on the card slots of the fixing cone through the thrust to fix the rubber cylinder after setting. Among them, the perforating gun and the bridge plug setting part are made of a soluble alloy material.

[0086] Fourthly, the present invention provides a computer program product, including a computer program / instructions, and when the computer program / instructions are executed by a processor, the steps of a perforating method based on a cable-free connection are implemented.

[0087] Fifthly, the present invention provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the steps of a perforating method based on a cable-free connection are implemented.

[0088] Sixthly, the present invention provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of a perforating method based on a cable-free connection are implemented.

[0089] As can be seen from the above description, the embodiments of the present invention provide a perforator and a perforating method based on a cable-free connection. The perforator successively includes from top to bottom in the wellbore depth: a data return part, an electromagnetic deceleration part, a detonation disconnection part, and a perforating gun; where: the data return part is used to collect the perforating operation data underground, and the data return part at least includes a power part for the power of the perforator to return to the ground after the perforating operation; the electromagnetic deceleration part is used to control the magnetic force of the casing on the perforator and adjust the position of the perforator in the horizontal well section; the detonation disconnection part is used to perform detonation after the perforating operation to disconnect the detonation disconnection part and the perforating gun; the perforating gun is used to shoot the perforating charges inside it into the formation.

[0090] The perforating method applied to the above perforator includes: first, the magnetic positioning part and the gyroscope of the perforator perform positioning on the perforator according to the pre-acquired wellbore structure data, so that the current depth of the perforator is the preset perforating depth; the perforating gun of the perforator perforates the layer corresponding to the perforating depth; then, the detonation disconnection part of the perforator reduces the weight of the perforator; finally, the power part on the perforator provides thrust to make the perforator return to the ground, where the perforator stores the perforating operation data collected underground.

[0091] The present invention innovatively proposes a perforator and a corresponding perforation method for perforation operations in a cable-free manner, which can replace the conventional downhole perforation and completion operations connected by cables or conveyed by coiled tubing. It has the advantages of low operation cost and high completion efficiency, and solves the problems of cumbersome and time-consuming operation, high operation cost, and inability to perform continuous fracturing operations in traditional perforation technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0092] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0093] Figure 1 Structural schematic diagram of the power unit in the embodiment of the present invention;

[0094] Figure 2 Structural schematic diagram of the electromagnetic deceleration unit in the embodiment of the present invention;

[0095] Figure 3 Structural schematic diagram of the buoyancy chamber in the embodiment of the present invention;

[0096] Figure 4 Structural schematic diagram of the detonation disconnection unit in the embodiment of the present invention;

[0097] Figure 5 Structural schematic diagram of the perforating gun in the embodiment of the present invention;

[0098] Figure 6 Structural schematic of the bridge plug setting unit in the embodiment of the present invention Figure 1 ;

[0099] Figure 7 Structural schematic of the bridge plug setting unit in the embodiment of the present invention Figure 2 ;

[0100] Figure 8 Structural schematic of the elastic claw in the embodiment of the present invention Figure 1 ;

[0101] Figure 9 Structural schematic of the elastic claw in the embodiment of the present invention Figure 2 ;

[0102] Figure 10 Structural schematic of the elastic claw in the embodiment of the present invention Figure 3 ;

[0103] Figure 11Schematic diagram of the inclined surface of the fixed cone in the embodiment of the present invention;

[0104] Figure 12 Schematic diagram of the structure of the cableless-connected perforator in the embodiment of the present invention Figure 1 ;

[0105] Figure 13 Flow chart of step 100 in the cableless-connected perforation method provided in the embodiment of the present invention;

[0106] Figure 14 Flow chart of step 300 in the cableless-connected perforation method provided in the embodiment of the present invention;

[0107] Figure 15 Schematic diagram of the structure of the cableless-connected perforator in the embodiment of the present invention Figure 2 ;

[0108] Figure 16 Schematic diagram of the structure of the cableless-connected perforator in the embodiment of the present invention Figure 3 ;

[0109] Figure 17 Schematic diagram of the structure of the cableless-connected perforator in the embodiment of the present invention Figure 4 ;

[0110] Figure 18 Schematic diagram of the structure of the cableless-connected perforator in the embodiment of the present invention Figure 5 ;

[0111] Figure 19 Schematic diagram of the structure of the cableless-connected perforator in the embodiment of the present invention Figure 6 ;

[0112] Figure 20 Schematic diagram of the structure of the cableless-connected perforator in the embodiment of the present invention Figure 7 ;

[0113] Figure 21 Flow chart of step 180 in the cableless-connected perforation method provided in the embodiment of the present invention Figure 1 ;

[0114] Figure 22 Flow chart of step 180 in the cableless-connected perforation method provided in the embodiment of the present invention Figure 2 ;

[0115] Figure 23 Flow chart of the cableless-connected perforation method in the specific application example of the present invention.

[0116] Figure 24 This is the mind map of the perforation method based on cable-free connection in the specific application example of the present invention.

[0117] Figure 25 This is the structural schematic diagram of the cable-free connection based perforation system in the embodiment of the present invention Figure 1 ;

[0118] Figure 26 This is the structural schematic diagram of the depth positioning module 10 in the embodiment of the present invention;

[0119] Figure 27 This is the structural schematic diagram of the weight reduction module 30 in the embodiment of the present invention;

[0120] Figure 28 This is the structural schematic diagram of the cable-free connection based perforation system in the embodiment of the present invention Figure 2 ;

[0121] Figure 29 This is the structural schematic diagram of the cable-free connection based perforation system in the embodiment of the present invention Figure 3 ;

[0122] Figure 30 This is the structural schematic diagram of the cable-free connection based perforation system in the embodiment of the present invention Figure 4 ;

[0123] Figure 31 This is the structural schematic diagram of the cable-free connection based perforation system in the embodiment of the present invention Figure 5 ;

[0124] Figure 32 This is the structural schematic diagram of the wellbore setting module 90 in the embodiment of the present invention Figure 1 ;

[0125] Figure 33 This is the structural schematic diagram of the wellbore setting module 90 in the embodiment of the present invention Figure 2 ;

[0126] Figure 34 This is the physical structure schematic diagram of the electronic device provided by an embodiment of the present invention. Detailed implementation manners

[0127] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0128] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0129] It should be noted that the terms "including" and "having" in the specification and claims of this application and any variations thereof in the above-mentioned drawings are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices. Without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The following will describe this application in detail with reference to the drawings and in combination with the embodiments.

[0130] In the technical solution of this application, the acquisition, storage, use, processing, etc. of data all comply with the relevant regulations of laws and regulations.

[0131] An embodiment of the present invention provides a specific implementation manner of a perforator based on cableless connection. The perforator includes, from top to bottom in the wellbore depth: a data return part, an electromagnetic deceleration part, a detonation disconnection part, and a perforating gun. Specifically:

[0132] The data return part is used to collect the perforation operation data underground. The data return part at least includes a power part, which is used for the power of the perforator to return to the ground after the perforation operation.

[0133] See Figure 1 , the shape of the data return part 1 is preferably a sphere, and such a design can make it easier to return to the ground in the wellbore.

[0134] The electromagnetic deceleration part is used to control the magnetic force of the casing on the perforator and adjust the position of the perforator in the horizontal well section.

[0135] See Figure 2 and Figure 3, the electromagnetic deceleration unit 2 consists of multi-sided electromagnets (arranged around the main body of the electromagnetic deceleration unit), speed sensors, current adjustment chips, current circuits, etc.; it uses the suction force of the sleeve on the magnet to increase the friction force opposite to the moving speed of the perforator, and controls the magnitude of the current in the electromagnet mechanism according to the change in the descending speed of the perforator, thereby changing the magnitude of the electromagnetic force of the electromagnet, so as to achieve the purpose of controlling the descending speed of the perforator and adjusting the position of the perforator in the vertical well section and the horizontal well section.

[0136] The detonation disconnection part is used for detonating after the perforation operation to disconnect the detonation disconnection part and the perforating gun;

[0137] See Figure 4 , the detonation disconnection part consists of a pyrotechnic release 3-1, an ignition head 3-2, a chip 3-3, etc. The pyrotechnic release is located at the head of the detonation disconnection part and is connected to the electromagnetic deceleration part. After the perforation operation is completed, it is used to discard all components below the electromagnetic deceleration part to reduce the total weight of the perforator to be returned to the ground, and greatly reduce the load of the power part of the data return part.

[0138] The perforating gun is used to shoot the perforating charges inside it into the formation.

[0139] See Figure 5 , the perforating gun mainly consists of a female joint, a perforating gun body 5-1, etc. The perforating gun is installed at the tail of the detonation disconnection part. The perforating gun is improved based on the existing structure and is made of a soluble alloy material, so that the body of the perforating gun self-destructs into debris and is discarded at the bottom of the well after perforation.

[0140] The above adjacent components are all connected by trapezoidal threads. The adjacent components are butt-jointed to form a cavity extending along the axis direction. The maximum diameter of the cross-section of each component does not exceed the outer diameter of the commonly used perforating gun to which it is connected. A male joint structure is provided on the butting surface of one of the two butting components, and a female joint structure for concave-convex positioning and cooperation with the male joint structure is provided on the corresponding butting surface of the other component. The mutually concave-convex matching thread structure ensures the position accuracy of the two adjacent components in the radial direction when they are butted.

[0141] From the above description, it can be seen that the embodiment of the present invention provides a perforator based on cable-free connection. The perforator successively includes from top to bottom in the wellbore depth: a data return part, an electromagnetic deceleration part, a detonation disconnection part, and a perforating gun; among them: the data return part is used to collect the perforation operation data underground, and the data return part at least includes a power part for the power of the perforator to return to the ground after the perforation operation; the electromagnetic deceleration part is used to control the magnetic force of the casing on the perforator and adjust the position of the perforator in the horizontal well section; the detonation disconnection part is used for detonating after the perforation operation to disconnect the detonation disconnection part and the perforating gun; the perforating gun is used to shoot the perforating charges inside it into the formation.

[0142] The invention embodiment provides a perforator based on cable-free connection, which can provide upward power for the cable-free connection perforation equipment in the limited underground space, replace the conventional downhole operation mode, requires fewer surface equipment, has the advantages of simple operation, low operation cost and high operation efficiency, and solves the problems of long cable-down time for perforation operations, low utilization rate of surface equipment, and cumbersome operation for perforating a specific number of perforation clusters.

[0143] In some embodiments of the present invention, the power unit includes a propeller, a motor, a gyroscope and a battery;

[0144] See Figure 1 , the propeller 1-1 is used to provide thrust for the perforator. Further, the power unit also includes a propeller power control system, a motor cabin, a battery cabin (containing a battery 1-3 inside), etc. This power unit is used to more precisely adjust the position of the perforator when the perforator moves to the designated operation position, and serves as the main return power device after the perforation operation.

[0145] One end of the propeller 1-1 is threadedly connected to the other part of the data return module. The other end surface is designed with a curved surface structure more suitable for fluid entry according to the fluid flow characteristics, and a bearing for fixedly connecting the shaft is installed to fix the rotation shaft of the propeller 1-1. The propeller power control system realizes the automatic control of the underground depth of the perforator by regulating the output speed and torque of the motor. Moreover, the perforator has the characteristics of stable and reliable structure. In addition, the propeller 1-1 is a special propeller applicable to casing wells and small-diameter wells. The propeller component is exposed in the underground drilling fluid environment and is connected to the upper connection positioning structure and the coupling 1-2 through the rotation shaft to fix the radial displacement of the propeller 1-1. The special-shaped surface structures facilitating fluid flow are designed on the adjacent end surfaces of the propeller 1-1, and the C-shaped reinforcing ribs are used to fix the structures on both sides.

[0146] The detonation disconnection part further includes: a magnetic positioning part for performing a primary positioning of the perforator in the wellbore;

[0147] Specifically, the magnetic positioning part includes a pair of permanent magnets with opposite polarities and a coil. The permanent magnets will generate a constant magnetic field. During continuous logging, when it passes through the process of casing - collar - casing, it causes the ferromagnetic substances around it to change from thin to thick and then to thin, so that the magnetic flux passing through the coil per unit time changes from large to small and then from small to large, and an induced electromotive force will be generated in the coil. This induced electromotive force signal will be recorded on the logging curve, which represents the position (depth) of the collar. Compared with normal casing (or tubing), changes in the structure, thickness and deformation of the pipe string in the well, the generation of holes and cracks, and the presence of downhole tools all mean that the ferromagnetic substances in the well have changed, and obvious anomalies will be shown on the logging curve.

[0148] In metal cased wells, CCL (Continuous Current Locator) logging curves and natural gamma logging curves can accurately verify the depth of the casing string and the formation (referred to as "depth calibration"). The collar locator can be combined with many logging instruments for logging, such as gamma-well temperature-collar locator combined logging, acoustic variable density-natural gamma-collar locator combined logging, etc.

[0149] The power unit is also used to perform secondary positioning of the perforator through the gyroscope after the primary positioning.

[0150] Based on the one-time positioning, the perforator can be roughly located at the perforating depth, but it is not accurate enough at this time. It is necessary to use a gyroscope (preferably a nine-axis gyroscope) to determine the descent speed of the perforator and accurately calibrate the depth of the perforator based on the one-time positioning result.

[0151] In some embodiments of the present invention, the battery includes at least two parts, wherein at least one part of the battery is arranged below the detonation disconnecting portion.

[0152] It is understandable that this battery arrangement can provide sufficient power during the descent of the perforator and convert it into thrust to propel the perforator. After the perforator completes perforating, the detonating disconnect part is detonated to disconnect the components below it, and then the exhausted battery is discarded to reduce the weight of the perforator during the return to the ground. It should be pointed out that during the descent of the perforator, the battery below the detonating disconnect part should be used first, and the battery above the detonating disconnect part should be used during the return to the ground.

[0153] In some embodiments of the present invention, the perforating instrument based on the non-cable connection further includes:

[0154] A salvaging head, arranged on the upper part of the data return part, for salvaging the perforator;

[0155] On the one hand, when the perforator returns to the wellhead on the ground, the data is retrieved by grabbing the fishing head to complete the perforating operation.

[0156] On the other hand, when the perforator fails to complete the designated operation or an accident occurs underground, the detonation disconnection unit uses explosives to cut off the data line of the data return unit, and the data return unit automatically floats up with the latest data. After being salvaged from the wellhead, it is convenient for ground staff to take countermeasures according to the underground situation. Or when the perforator performs multi-cluster perforation operations, the data return unit takes on the role of data storage and transmission.

[0157] The buoyancy chamber is arranged on the upper part of the electromagnetic deceleration part, and is used to reduce the descending speed of the perforator in the wellbore and provide power for the perforator to return to the ground.

[0158] See Figure 3 , the buoyancy chamber 4 not only bears the deceleration function when the perforator falls, but also provides the buoyancy required for returning after the perforation operation. The effective reaction thrust provided by each section of the buoyancy chamber is fixed, and the number of buoyancy chambers can be increased or decreased according to the actual working conditions to control the buoyancy.

[0159] In some embodiments of the present invention, see Figure 5 , the perforating gun includes: a perforating gun body 5-1 and a bridge plug setting part 5-2, wherein:

[0160] The bridge plug setting part 5-2 is arranged at the lower part of the perforating gun body 5-1 and is used for setting the formation;

[0161] The perforating gun body 5-1 and the bridge plug setting part 5-2 are made of a soluble alloy material.

[0162] The bridge plug setting part 5-2 is composed of a newly designed setting tool, adopts a pyrotechnic setting method, and uses the principle of different shearing forces of large and small pins to complete the setting and releasing operations. At the same time, the structure of the bridge plug is improved, and a set of slips are used for the operation, which greatly reduces the weight of the setting tool. It can be understood that the soluble bridge plug setting part 5-2 added to the perforator forms a more convenient bridge-perforation combined operation technology, which can greatly improve the perforation operation efficiency and provide conditions for staged fracturing. It has great advantages in the fields of old well reconstruction and oil and gas well stimulation.

[0163] In some embodiments of the present invention, see Figure 6 , the bridge plug setting part includes: a gunpowder chamber 6-1, a release 6-3, a push tube 6-5, a rubber tube 6-6, a fixing cone 6-7 and a slip 6-8. Specifically:

[0164] The gunpowder chamber 6-1: is arranged at the bottom of the perforating gun body 5-1, is used for providing setting power, and is internally provided with a first pin 6-2;

[0165] The release 6-3 is arranged below the gunpowder chamber 6-1 and is provided with a second pin 6-4 (see Figure 7 ), and the second pin 6-4 is used to separate the bridge plug setting from the perforator;

[0166] The shearing force at which the first pin 6-1 breaks is less than the shearing force at which the second pin 6-4 breaks;

[0167] The push tube 6-5 is sleeved outside the gunpowder chamber 6-1 and the release 6-3;

[0168] The rubber tube 6-6 is arranged below the push tube 6-5 and is used for sealing the wellbore;

[0169] The fixed cone 6-7 is arranged at the lower part of the rubber cylinder 6-6 and is used to cooperate with the pushing cylinder 6-5 to extrude the rubber cylinder 6-6, and the end of the fixed cone 6-7 facing the bottom of the well is conical;

[0170] The slips 6-8 are sleeved on the conical part of the fixed cone 6-7 and are used to block the wellbore.

[0171] The setting principle of the above bridge plug setting part is as follows: The gunpowder in the gunpowder chamber 6-1 is ignited, and the high-energy gas generated by combustion enters the annulus through the channel 6-9. The first pin 6-2 (or called the setting pin, which is used to make the pushing cylinder 6-5 break away from the gunpowder chamber 6-1 and move towards the fixed cone 6-7) breaks first due to the small shear force. The gas pushes the pushing cylinder 6-5 to move right (down) (the gunpowder chamber 6-1 is connected to the releasing tool 6-3 and the mandrel 6-10, and the mandrel 6-10 has a tendency to move relatively left). The fixed cone 6-7 also moves downward; Since the setting head 6-11 is connected and fixed to the mandrel 6-10, the setting head 6-11 moves left (up) relative to the slips 6-8, pushing the slips 6-8 to set; At the same time, after the slips 6-8 are set, the rubber cylinder 6-6 is extruded by the fixed cone 6-7 and the pushing cylinder 6-5 for secondary setting.

[0172] In some embodiments of the present invention, see Figure 8 、 Figure 9 and Figure 10 , the bridge plug setting part further includes:

[0173] The elastic claw 6-12 is arranged inside the rubber cylinder 6-6, and the end facing the bottom of the well is a claw structure 6-12-1, and the claw structure 6-12-1 is used to cooperate with the card slot 6-7-1 of the fixed cone 6-7 to fix the rubber cylinder after setting.

[0174] After the rubber cylinder 6-6 and the slips 6-8 are set, the remaining high-energy gas pushes the pushing cylinder 6-5 and the elastic claw 6-12. The elastic claw 6-12 is subjected to the thrust and is compressed inward along the inclined surface 6-13 in contact with the fixed cone 6-7 (see Figure 11 ), and at the same time moves right (down), so that the rubber cylinder 6-6 is completely set and will not rebound to cause the setting to fail; After all setting operations are completed, the pushing cylinder 6-5 cannot move downward, and the second pin 6-4 (which can also be called the releasing pin) connecting the gunpowder chamber 6-1 to the releasing tool 6-3 breaks, completing the releasing operation; The setting operation is completed. And when the subsequent fracturing operation is carried out, the releasing tool 6-3 and the pushing cylinder 6-5 in the setting tool are pressed downward by the fracturing pressure, and the setting effect is better.

[0175] As can be seen from the above description, the embodiments of the present invention provide a cableless connection-based perforator, which has the following beneficial effects:

[0176] 1. The perforator adopts a modular design for each component and is combined with perforating guns of different specifications, which can be applied to different oil and gas wells, replacing the conventional downhole perforating completion operations connected by cable or conveyed by coiled tubing. It has the advantages of low operation cost and high completion efficiency, and solves the problems of cumbersome and time-consuming operation, high operation cost, and inability to perform continuous fracturing operations in traditional perforating technologies.

[0177] 2. Due to the action of gravity in traditional perforating operations, the perforating gun sinks to the bottom of the horizontal well, resulting in different sizes of perforation holes after perforation, seriously affecting the subsequent fracturing operation effect. The relevant oil service companies in the industry have designed an equal-aperture perforator for this problem, but have not fundamentally solved the problem of different perforation hole sizes in horizontal wells.

[0178] The perforator provided by the embodiment of the present invention overcomes the deficiencies of traditional perforating operations. After the perforator enters the horizontal section, due to the action of gravity, it sinks to the bottom of the well. The gyroscope detects the attitude of the perforator and sends a signal to adjust the magnetic force of the electromagnets on two opposite surfaces of the electromagnet device through a chip, so that the electromagnet close to the bottom has no magnetism, while the magnetic force of the electromagnet close to the top of the casing in the well increases. Finally, under the action of buoyancy and the suction force provided by the electromagnet close to the top of the casing, it reaches an equilibrium with the self-gravity of the perforator. The perforator suspends at the center of the casing, and the subsequent perforating operation can achieve equal-aperture perforation in horizontal wells.

[0179] 3. Innovative design of the deceleration method. The perforator provided by the embodiment of the present invention no longer relies solely on a certain deceleration method. It combines buoyancy, the external power of the propeller, and the suction force of the magnet. In the vertical well section, it relies on buoyancy and the suction force of the electromagnet on the casing to decelerate. The buoyancy provided by the buoyancy chamber is fixed. According to the falling speed of the perforator, the current passing through the electromagnet is adjusted at any time to change the magnetic force of the electromagnet, thereby changing the friction force between the electromagnet and the casing to control the descending speed of the perforator. When the perforator moves near the perforating operation position, the propeller starts to act to precisely adjust the position of the perforator.

[0180] The above deceleration method applies the buoyancy chamber and the electromagnet device to the downhole, with a simple structure, convenient and feasible operation, and can solve the problem of different perforation hole sizes in the horizontal section. If only the external power of the propeller is used, the volume and weight of the battery required by the perforator will increase greatly, and equal-aperture perforation cannot be achieved in the horizontal section. If only buoyancy is used, it is very difficult to control the accuracy of the perforating operation position of the perforator, and equal-aperture perforation cannot be achieved in the horizontal section.

[0181] 4. Improvement of the packer tool. By utilizing the principle of different shearing forces of large and small pins, the setting and releasing operations of the packer tool are completed. Compared with traditional methods such as setting by dropping a ball and electric setting, it has the advantages of simple structure and concise operation, and greatly reduces the weight of the packer tool, which can be widely used in various occasions. At the same time, the internal structure of the bridge plug module is improved. Through the shrinkage of the elastic claws, the elastic claws are embedded with the fixed ring during the setting process, ensuring the setting effect and improving the setting stability.

[0182] An embodiment of the present invention provides a specific implementation method of a cableless connection-based perforation method using the above-mentioned cableless connection-based perforation instrument. Refer to Figure 12 , and the method specifically includes the following contents:

[0183] Step 100: The magnetic positioning part and the gyroscope of the perforation instrument position the perforation instrument according to the pre-acquired wellbore structure data, so that the current depth of the perforation instrument is the preset perforation depth;

[0184] Step 200: The perforating gun of the perforation instrument perforates the formation corresponding to the perforation depth;

[0185] Step 300: The detonation disconnecting part of the perforation instrument reduces the weight of the perforation instrument;

[0186] Step 400: The power part on the perforation instrument provides thrust to make the perforation instrument return to the ground, where the perforation instrument stores the perforation operation data collected underground.

[0187] As can be seen from the above description, the embodiment of the present invention provides a cableless connection-based perforation method, including the magnetic positioning part and the gyroscope of the perforation instrument positioning the perforation instrument according to the pre-acquired wellbore structure data, so that the current depth of the perforation instrument is the preset perforation depth; the perforating gun of the perforation instrument perforates the formation corresponding to the perforation depth; the detonation disconnecting part of the perforation instrument reduces the weight of the perforation instrument; the power part on the perforation instrument provides thrust to make the perforation instrument return to the ground, where the perforation instrument stores the perforation operation data collected underground.

[0188] The present invention innovatively proposes a perforation method for perforation operations in a cableless manner, which can replace the conventional downhole perforation and completion operations using cable connections or coiled tubing conveyance. It has the advantages of low operation cost and high completion efficiency, and solves the problems of cumbersome and time-consuming operation, high operation cost, and inability to perform continuous fracturing operations in traditional perforation technologies.

[0189] In some embodiments of the present invention, the wellbore structure data in step 100 includes: the size of the casing used, such as length, coupling type, etc. After obtaining the wellbore structure data, it can be used in cooperation with the magnetic positioning part to roughly calibrate the current depth of the perforation instrument.

[0190] In some embodiments of the present invention, for step 200, a perforating gun is a tool used for perforating operations in oil wells or other wellbores. Perforating refers to connecting the wellbore with the formation through the wellbore wall so that oil, gas or other fluids can flow into the wellbore. Preferably, the perforating gun includes:

[0191] Perforating gun body: It is the core component of the perforating instrument, which contains a detonating device and steel bullets. The perforating gun is detonated by an electrical signal or a pressure signal, thereby shooting the steel bullets into the wellbore wall.

[0192] Perforating bullet: The perforating bullet is a hollow metal steel bullet with a detonating device installed inside. When the detonating device is triggered, the perforating bullet will generate high-pressure gas or an explosion, thereby piercing through the wellbore wall.

[0193] Control system: The perforating gun is equipped with a control system to control the time, frequency and position of the perforating operation. The control system is usually controlled by a computer or other electronic devices and can be programmed and adjusted as needed.

[0194] In some embodiments of the present invention, for step 300 and step 400, since the perforating instrument of the embodiment of the present application is wirelessly connected, when the perforating operation is completed, it is necessary to reduce the weight of the perforating instrument so that the perforating instrument can return to the ground under the push of the power unit.

[0195] In some embodiments of the present invention, referring to Figure 13 , step 100 includes:

[0196] Step 101: The magnetic positioning part of the perforating instrument performs a primary positioning on the perforating instrument according to the wellbore structure data;

[0197] It can be understood that the result of the primary positioning is a general depth range, and the error is generally within 10 meters. Therefore, further precise positioning is required.

[0198] Step 102: The gyroscope determines the current descending speed of the perforating instrument;

[0199] Step 103: The magnetic positioning part performs a secondary positioning on the perforating instrument according to the current descending speed so that the current depth is the perforating depth.

[0200] In step 102 and step 103, on the basis of the primary positioning, combined with the current descending speed and the distance to be moved, the time for the perforating instrument to further descend is calculated. When this time is reached, the current depth is the perforating depth.

[0201] In some embodiments of the present invention, referring to Figure 14 , step 300 includes:

[0202] Step 301: The detonation disconnecting part detonates the pyrotechnic release device inside it and causes it to break, so that the detonation disconnecting part and the components below it are separated from the perforating tool.

[0203] Preferably, the detonation disconnecting part consists of a pyrotechnic release device, an ignition head, a chip, etc. All components below the electromagnetic deceleration part are discarded to reduce the total weight of the cabin body to be returned to the ground. At the same time, the number of batteries used is also reduced, greatly reducing the load on the propeller power mechanism. The above-mentioned pyrotechnic release device is a unique new structure, which consists of a detonating fuse, an explosion-proof seal, a sealing ring, an explosive bin, a release seat, etc. A thinned blasting area is left, and the release seat blasting area is blown up when the tail structure needs to be discarded; the sealing ring is installed at the connection between the upper joint and the release seat; the release seat has different diameter specifications for matching various specifications of perforating guns, and can be applied to the perforating operations of various oil and gas wells.

[0204] In some embodiments of the present invention, see Figure 15 , before step 100 of the cable-free connection based perforating method, it further includes:

[0205] Step 90: The power part and the buoyancy tank of the perforating tool control the descending speed of the perforating tool in the wellbore;

[0206] In addition, the descending speed of the perforating tool can also be controlled in the following way. According to the change of the descending speed of the perforating tool, the magnitude of the current in the electromagnet mechanism of the electromagnetic deceleration part is controlled, so as to change the magnitude of the electromagnetic force of the electromagnet, so as to achieve the purpose of controlling the descending speed of the perforating tool.

[0207] In some embodiments of the present invention, see Figure 16 , after step 300 of the cable-free connection based perforating method, it further includes:

[0208] Step 310: The buoyancy tank provides buoyancy to make the perforating tool return to the ground.

[0209] That is, during the process of the perforating tool returning to the ground, the thrust required by it is jointly provided by the power part and the buoyancy tank, and the number of buoyancy tanks can be increased or decreased according to the actual working conditions to increase the thrust.

[0210] In some embodiments of the present invention, see Figure 17 , before step 200 of the cable-free connection based perforating method, it further includes:

[0211] Step 190: The electromagnetic deceleration part of the perforating tool controls the magnetic force between the perforating tool and the casing, so that the perforating tool is located on the central axis of the casing;

[0212] Specifically, see Figure 2, by controlling the magnitude of the current in the electromagnet mechanism of the electromagnetic deceleration section, to adjust the

[0213] In some embodiments of the present invention, refer to Figure 18 , based on the cable-free connection perforation method, after step 200, it further includes:

[0214] Step 210: The electromagnetic deceleration section eliminates the magnetic force.

[0215] In some embodiments of the present invention, the perforator includes at least two electromagnetic deceleration sections, respectively located at the top and the top of the perforator; refer to Figure 19 , based on the cable-free connection perforation method, it further includes:

[0216] Step 500: When the perforation well section is a horizontal well section, the two electromagnetic deceleration sections adjust the magnetic force received by the perforator in the casing, so that the perforator is located on the central axis of the casing.

[0217] After the perforator enters the horizontal section, due to the action of gravity, it sinks to the bottom of the well. The gyroscope detects the attitude of the perforator and sends a signal. The electromagnetic deceleration section is adjusted through the chip to change the electromagnetic force magnitude of multiple faces of the electromagnet; the electromagnet near the bottom has no magnetism, while the electromagnetic force of the electromagnet near the top of the casing in the well increases. Finally, under the action of buoyancy and the suction force provided by the electromagnet near the top of the casing, it reaches equilibrium with the self-gravity of the perforator; the perforator floats in the center of the casing, and the subsequent perforation operation can achieve equal-aperture perforation in horizontal wells.

[0218] In some embodiments of the present invention, refer to Figure 20 , based on the cable-free connection perforation method, before step 200, it further includes:

[0219] Step 180: The bridge plug setting part at the bottom of the perforator sets the bridge plug for the wellbore.

[0220] Bridge plug setting is a well completion operation technique used to block a certain section of the wellbore and prevent the flow of fluids. It is usually used in well workovers, perforations, cementing, etc. Its principle is to place a special packer in the wellbore, either above or below the area to be blocked. The packer consists of pipes, gaskets, valves, etc., and the flow of fluids can be controlled by controlling the opening and closing of the valves.

[0221] When performing the bridge plug setting operation, packers are placed above and below the target area respectively, and then the packers are closed by controlling the valves, thereby preventing the flow of fluids. In this way, the wellbore can be divided into different sections, facilitating subsequent operation procedures such as perforation, workover, and cementing.

[0222] In some embodiments of the present invention, refer toFigure 21 , step 180 includes:

[0223] Step 1801: Ignite the gunpowder inside the gunpowder chamber of the bridge plug, causing the first pin inside the gunpowder chamber to break, and generating a thrust to push the push barrel towards the fixed cone, so as to squeeze the rubber barrel between the push barrel and the fixed cone, and make the rubber barrel seal the wellbore;

[0224] Step 1802: One end of the fixed cone with a conical shape enters into the slips through the thrust, so as to make the slips seal the wellbore;

[0225] In step 1081 and step 1082, after the gunpowder in the gunpowder chamber is ignited, the high-energy gas generated by combustion enters the annulus through the channel. The first pin breaks first due to the smaller shearing force. The gas pushes the push barrel to move downward (the gunpowder chamber connects the release joint and the mandrel, and the mandrel has a relative upward movement tendency), and the fixed cone also moves downward; Since the seat head is connected and fixed to the mandrel, the seat head moves upward relative to the slips, pushing the slips to seal; At the same time, after the slips are sealed, the rubber barrel is squeezed by the fixed cone and the push barrel to perform a secondary seal.

[0226] Step 1803: The second pin in the release joint at the lower part of the gunpowder chamber breaks through the thrust, so that the bridge plug seal is disengaged from the perforating instrument, wherein the shearing force for the breakage of the first pin is less than the shearing force for the breakage of the second pin.

[0227] In some embodiments of the present invention, see Figure 22 , step 180 further includes:

[0228] Step 1804: The elastic claws inside the rubber barrel are stuck on the card slots of the fixed cone through the thrust to fix the rubber barrel after sealing, wherein the perforating gun and the bridge plug sealing part are made of a soluble alloy material.

[0229] After the rubber barrel and the slips are sealed, the remaining high-energy gas pushes the push barrel and the elastic claws. The elastic claws are subjected to the thrust, compress inward along the inclined plane in contact with the fixed cone, and move downward at the same time, so that the rubber barrel is completely sealed and will not rebound to cause the seal to fail; After all the sealing work is completed, the push barrel cannot move downward, and the second pin connecting the gunpowder chamber to the release joint breaks, completing the release joint; The sealing operation is completed. And when the subsequent fracturing operation is carried out, at this time, the release joint and the push barrel in the sealing tool are pressed downward by the fracturing pressure, and the sealing effect is better.

[0230] To further illustrate this solution, see Figure 23 and Figure 24 , the present invention also provides a specific application example of a perforating method based on cable-free connection.

[0231] S1: Determine the diameter of the oil and gas well to select a suitable perforating instrument.

[0232] According to the requirements of perforation operations, determine the depth of the downhole and the density of the downhole fluid, and modify the chip information according to the parameters to adjust the chip positioning depth.

[0233] S2: Descend to the perforation depth.

[0234] Assemble the various components of the perforator. After checking the chip parameter settings and the assembly and fixation of the tool string, lower it into the oil and gas well through the wellhead device. During the lowering process, in the vertical section: the device automatically descends under the action of gravity, and by controlling the electromagnetic deceleration part, the stable control of the falling speed of the perforator is achieved. After the CCL detects the perforation operation position (using magnetic positioning technology to real-time monitor the falling position of the perforator. In addition, after the igniter is the chip electronic cabin. The chip electronic cabin section is an important part of the automatic perforation technology, and realizes the automatic perforation control of the perforating gun downhole by using pattern recognition technology, advanced data analysis and signal processing methods.), the preliminary positioning of the perforator is completed and the perforation operation is carried out. If perforation is required in the horizontal section: after the perforator enters the horizontal section, it sinks to the bottom of the well under the action of gravity. The gyroscope detects the attitude of the perforator and sends a signal. By adjusting the electromagnetic force of the two opposite faces of the electromagnetic iron device through the chip; make the electromagnetic iron close to the bottom have no magnetism, while the electromagnetic force of the electromagnetic iron close to the top of the well casing increases. Finally, under the action of buoyancy and the suction force provided by the electromagnetic iron close to the top of the casing to the casing, it reaches equilibrium with the self-gravity of the perforator; the perforator suspends in the center of the casing, and then uses the power provided by the propeller to move forward to reach the designated position.

[0235] Specifically, refer to Figure 24 , when the descending speed is greater than 4 m / s, first close the electromagnetic circuit of the electromagnetic deceleration part to increase the current of the electromagnetic circuit of the electromagnetic mechanism, thereby increasing the electromagnetic force to reduce the descending speed of the perforator. On the contrary, when the descending speed is too small, reverse the above operation to increase the descending speed of the perforator. When reaching the predetermined perforation operation depth, send a CCL signal and adjust the position of the perforator through the propeller to achieve precise positioning.

[0236] S3: Set the bridge plug and perform the perforation operation.

[0237] After the perforator reaches the predetermined perforation operation position, set the bridge plug. After the setting operation is completed, adjust the position of the perforator by relying on the power provided by the propeller, and rely on the CCL to ensure that the perforator accurately reaches the predetermined perforation operation position. After the perforation operation, the perforating gun explodes into easily soluble fragments, activate the pyrotechnic release, and discard the structure below the pyrotechnic release.

[0238] S4: Return the perforator to the ground.

[0239] The output power of the motor increases, causing the propeller to provide increased thrust, pushing the data return device back to the ground, grasping the fishing head at the wellhead position, and completing the operation.

[0240] It should be noted that when the perforator fails to complete the specified operation or an accident occurs underground, the ball dropping device uses explosives to break the data line for transmitting information of the data return ball. The ball automatically floats up with the latest data. After fishing at the wellhead, it is convenient for ground staff to take countermeasures according to the underground situation. Or when the perforator performs multi-cluster perforation operations, the data return ball undertakes the functions of data storage and transmission.

[0241] Based on the same inventive concept, an embodiment of the present application further provides a cableless connection-based perforation system, which can be used to implement the method described in the above embodiments, as in the following embodiments. Since the principle of solving problems by the cableless connection-based perforation system is similar to that of the cableless connection-based perforation method, the implementation of the cableless connection-based perforation system can refer to the implementation of the cableless connection-based perforation method, and the repeated parts will not be described again. Hereinafter, the term "unit" or "module" can be a combination of software and / or hardware that can achieve a predetermined function. Although the systems described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware is also possible and contemplated.

[0242] An embodiment of the present invention provides a specific implementation manner of a cableless connection-based perforation system capable of implementing a cableless connection-based perforation method, wherein, referring to Figure 25 , the cableless connection-based perforation system includes:

[0243] A depth positioning module 10, configured to position the perforator according to pre-acquired wellbore structure data, the magnetic positioning part of the perforator, and a gyroscope, so that the current depth of the perforator is a preset perforation depth;

[0244] A layer perforation module 20, configured to perforate the layer corresponding to the perforation depth through the perforating gun of the perforator;

[0245] A weight reduction module 30, configured to reduce the weight of the perforator through the detonation disconnecting part of the perforator;

[0246] A perforator return first module 40, configured to return the perforator to the ground through the thrust provided by the power part on the perforator, wherein the perforator stores the perforation operation data collected underground.

[0247] In some embodiments of the present invention, referring to Figure 26 , the depth positioning module 10 includes:

[0248] The primary positioning unit 10a is configured to perform primary positioning on the perforator according to the wellbore structure data and the magnetic positioning part of the perforator;

[0249] The download speed determination unit 10b is configured to determine the current descending speed of the perforator according to the gyroscope;

[0250] The secondary positioning unit 10c is configured to perform secondary positioning on the perforator according to the current descending speed, so that the current depth is the perforation depth.

[0251] In some embodiments of the present invention, referring to Figure 27 , the weight reduction module 30 includes:

[0252] The weight reduction unit 30a is configured to detach the detonating disconnecting part and its subsequent components from the perforator by detonating the pyrotechnic release inside the detonating disconnecting part and causing it to break.

[0253] In some embodiments of the present invention, referring to Figure 28 , the perforation system based on a cableless-connected perforator further includes:

[0254] The descending speed control module 40 is configured to control the descending speed of the perforator in the wellbore through the power unit and the buoyancy chamber of the perforator;

[0255] The perforator return second module 50 is configured to return the perforator to the ground by the buoyancy provided by the buoyancy chamber.

[0256] In some embodiments of the present invention, referring to Figure 29 , the perforation system based on a cableless-connected perforator further includes:

[0257] The position adjustment module 60 is configured to control the magnetic force between the perforator and the casing through the electromagnetic deceleration part of the perforator, so that the perforator is located on the central axis of the casing;

[0258] The magnetic force elimination module 70 is configured to eliminate the magnetic force through the electromagnetic deceleration part.

[0259] In some embodiments of the present invention, in the perforation system based on a cableless-connected perforator, the perforator includes at least two electromagnetic deceleration parts, which are respectively located at the top and the top of the perforator; referring to Figure 30 , the perforation system based on a cableless-connected perforator further includes:

[0260] The magnetic force adjustment module 80 is configured to adjust the magnetic force received by the perforator in the casing through the two electromagnetic deceleration parts when the perforation interval is a horizontal well interval, so that the perforator is located on the central axis of the casing.

[0261] In some embodiments of the present invention, referring to Figure 31 , the perforation system based on a cableless-connected perforator further includes:

[0262] A wellbore setting module 90, configured to set the wellbore through a packer setting part at the bottom of the perforator.

[0263] In some embodiments of the present invention, referring to Figure 32 , the wellbore setting module 90 includes:

[0264] A primary setting unit 90a, configured to ignite the gunpowder inside the gunpowder chamber of the packer setting, break the first pin inside the gunpowder chamber, and generate a thrust to push the push tube towards the fixed cone, so as to squeeze the rubber cylinder between the push tube and the fixed cone, and set the rubber cylinder to seal the wellbore;

[0265] A secondary setting unit 90b, configured to make the conical end of the fixed cone enter into the slips through the thrust, so as to set the slips to seal the wellbore;

[0266] A packer detachment unit 90c, configured to break the second pin inside the release sleeve at the lower part of the gunpowder chamber through the thrust, so as to detach the packer setting from the perforator, wherein the shearing force for breaking the first pin is less than the shearing force for breaking the second pin.

[0267] In some embodiments of the present invention, referring to Figure 33 , the wellbore setting module 90 further includes:

[0268] A rubber cylinder fixing unit 90d, configured to make the elastic claws inside the rubber cylinder catch on the card slots of the fixed cone through the thrust, so as to fix the rubber cylinder after setting, wherein the perforating gun and the packer setting part are made of a soluble alloy material.

[0269] As can be seen from the above description, the embodiments of the present invention provide a perforation system based on a cableless connection, including: a depth positioning module, configured to position the perforator according to the pre-acquired wellbore structure data, the magnetic positioning part of the perforator, and the gyroscope, so that the current depth of the perforator is a preset perforation depth; a layer perforation module, configured to perforate the layer corresponding to the perforation depth through the perforating gun of the perforator; a weight reduction module, configured to reduce the weight of the perforator through the detonation disconnection part of the perforator; a perforator return first module, configured to make the perforator return to the ground through the thrust provided by the power part on the perforator, wherein the perforator stores the perforation operation data collected underground.

[0270] The present invention innovatively proposes a perforating system for perforating operations in a cable-free manner, which can replace the conventional downhole perforating and completion operations connected by cables or conveyed by coiled tubing. It has the advantages of low operation cost and high completion efficiency, and solves the problems of cumbersome and time-consuming operation, high operation cost, and inability to perform continuous fracturing operations in traditional perforating technologies.

[0271] The embodiments of the present application also provide a specific implementation manner of an electronic device that can implement all the steps in the above-mentioned perforating method based on cable-free connection. Refer to Figure 34 , and the electronic device specifically includes the following contents:

[0272] The electronic device 600 may further include: a communication module 110, an input unit 120, an audio processing unit 130, a display 160, and a power supply 170. It should be noted that the electronic device 600 does not necessarily have to include Figure 34 all the components shown in Figure 34 ; in addition, the electronic device 600 may further include

[0273] components not shown in Figure 34 , and reference can be made to the prior art. It should be noted that this figure is exemplary; other types of structures can also be used to supplement or replace this structure to achieve telecommunication functions or other functions.

[0274] Among them, the memory 140 can be, for example, one or more of a buffer, a flash memory, a hard drive, a removable medium, a volatile memory, a non-volatile memory, or other suitable devices. It can store the above-mentioned information related to failures, and can also store programs for executing relevant information. And the processor 100 can execute the program stored in the memory 140 to implement information storage or processing, etc.

[0275] The input unit 120 provides input to the processor 100. The input unit 120 is, for example, a key or a touch input device. The power supply 170 is used to supply power to the electronic device 600. The display 160 is used to display display objects such as images and texts. The display 160 can be, for example, an LCD display, but is not limited thereto.

[0276] The memory 140 may be a solid-state memory, for example, a read-only memory (ROM), a random access memory (RAM), a SIM card, etc. It may also be a memory that stores information even when powered off, can be selectively erased and has more data. Examples of the memory 140 are sometimes referred to as EPROMs, etc. The memory 140 may also be some other type of device. The memory 140 includes a buffer 141 (sometimes referred to as a buffer memory). The memory 140 may include an application / function storage unit 142 for storing application programs and function programs or the processes for operating the electronic device 600 by the processor 100.

[0277] The memory 140 may further include a data storage unit 143 for storing data such as contacts, digital data, pictures, sounds, and / or any other data used by the electronic device. The driver storage unit 144 of the memory 140 may include various drivers of the electronic device for communication functions and / or for performing other functions of the electronic device (such as a messaging application, an address book application, etc.).

[0278] The communication module 110 includes a transmitter / receiver that transmits and receives signals via the antenna 111. The communication module 110 is coupled to the processor 100 to provide input signals and receive output signals, which may be the same as in the case of a conventional mobile communication terminal.

[0279] Based on different communication technologies, multiple communication modules 110 may be provided in the same electronic device, such as a cellular network module, a Bluetooth module, and / or a wireless local area network module, etc. The communication module 110 is also coupled to the speaker 131 and the microphone 132 via the audio processor 130 to provide an audio output via the speaker 131 and receive an audio input from the microphone 132, thereby implementing normal telecommunication functions. The audio processor 130 may include any suitable buffers, decoders, amplifiers, etc. Additionally, the audio processor 130 is also coupled to the processor 100, so that recording can be performed on the local machine through the microphone 132 and the sound stored on the local machine can be played through the speaker 131.

[0280] Each embodiment in this specification is described in a progressive manner. The same or similar parts among the embodiments can be referred to each other, and the key point of each embodiment is to illustrate the differences from other embodiments. In particular, for the hardware + program type embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiments.

[0281] The specific embodiments of this specification have been described above. Other embodiments are within the scope of the appended claims. In some cases, the acts or steps recited in the claims may be performed in a different order than in the embodiments and still achieve the desired results. Additionally, the processes depicted in the figures do not necessarily require the particular order or sequential order shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0282] Although this application provides method operation steps as described in the embodiments or flowcharts, based on routine or non-creative labor, there may be more or fewer operation steps. The order of steps listed in the embodiments is only one of the ways of the execution order of numerous steps and does not represent the only execution order. When the actual device or client product is executed, it may be executed in the order of the method shown in the embodiments or the figures or in parallel (for example, in an environment of parallel processors or multi-threaded processing).

[0283] Although the embodiments of this specification provide method operation steps as described in the embodiments or flowcharts, based on routine or non-creative means, there may be more or fewer operation steps. The order of steps listed in the embodiments is only one of the ways of the execution order of numerous steps and does not represent the only execution order. When the actual device or terminal product is executed, it may be executed in the order of the method shown in the embodiments or the figures or in parallel (for example, in an environment of parallel processors or multi-threaded processing, or even in a distributed data processing environment). The term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, product or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, product or device. Without further limitation, there is no exclusion of additional identical or equivalent elements in the process, method, product or device comprising the said elements.

[0284] For the convenience of description, when describing the above device, various modules are described separately according to their functions. Of course, when implementing the embodiments of this specification, the functions of each module can be implemented in the same or multiple software and / or hardware, or the modules implementing the same function can be realized by a combination of multiple sub-modules or sub-units, etc. The device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection to each other can be through some interfaces. The indirect coupling or communication connection of the device or unit can be in electrical, mechanical or other forms.

[0285] Those skilled in the art also know that in addition to implementing the controller in the form of pure computer-readable program code, the method steps can be logically programmed to enable the controller to be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, embedded microcontrollers, etc. to achieve the same function. Therefore, such a controller can be regarded as a hardware component, and the devices included therein for implementing various functions can also be regarded as the structures within the hardware component. Or even, the devices for implementing various functions can be regarded as both software modules for implementing the method and the structures within the hardware component.

[0286] The present invention is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, and the combination of processes and / or blocks in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the specified function in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0287] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured article including an instruction device, and the instruction device implements the specified function in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0288] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus, so that a series of operation steps are executed on the computer or other programmable apparatus to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions specified in one process Figure 1 one process or more processes and / or blocks Figure 1 steps for the functions specified in one block or more blocks.

[0289] In a typical configuration, a computing device includes one or more processors (CPUs), an input / output interface, a network interface, and memory.

[0290] The memory may include non-permanent memory in the form of computer-readable media, random access memory (RAM) and / or non-volatile memory such as read-only memory (ROM) or flash memory (flash RAM). Memory is an example of computer-readable media.

[0291] Computer-readable media includes both permanent and non-permanent, removable and non-removable media implemented by any method or technology for storing information. The information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile discs (DVD) or other optical storage, magnetic cassettes, magnetic tape disk storage or other magnetic storage devices, or any other non-transitory media that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media such as modulated data signals and carrier waves.

[0292] Those skilled in the art will appreciate that the embodiments of this specification may be provided as a method, system, or computer program product. Accordingly, the embodiments of this specification may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the embodiments of this specification may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0293] Embodiments of this specification can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. Embodiments of this specification can also be practiced in a distributed computing environment where tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules can be located in local and remote computer storage media including storage devices.

[0294] The various embodiments in this specification are described in a progressive manner. For the same or similar parts among the various embodiments, reference can be made to each other. Each embodiment focuses on the differences from other embodiments. In particular, for system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and reference can be made to the corresponding parts of the method embodiments for the relevant content. In the description of this specification, the description with reference to terms such as "an embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of this specification. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0295] The above description is only for the embodiments of this specification and does not limit the embodiments of this specification. For those skilled in the art, various changes and modifications can be made to the embodiments of this specification. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the embodiments of this specification shall be included within the scope of the claims of the embodiments of this specification.

Claims

1. A perforator based on cable-free connection, characterized in that, The wellbore depth from top to bottom sequentially includes: a data return section, an electromagnetic deceleration section, a detonation disconnection section, and a perforating gun; where: The data return section is used to collect downhole perforation operation data, and the data return section at least includes a power section for providing power for the logging-while-perforating tool to return to the surface after the perforation operation. The electromagnetic deceleration section is used to control the magnetic force of the casing on the logging-while-perforating tool and adjust the position of the logging-while-perforating tool in the horizontal well section. The detonation disconnection section is used to initiate detonation after the perforation operation to disconnect the detonation disconnection section and the perforating gun. The perforating gun is used to shoot the perforating charges inside it into the formation.

2. The perforating instrument according to claim 1, characterized in that, The power section includes a propeller, a motor, a gyroscope, and a battery. The detonation disconnection section further includes: a magnetic positioning section for performing a primary positioning of the logging-while-perforating tool in the wellbore. The power section is further used to perform a secondary positioning of the logging-while-perforating tool through the gyroscope after the primary positioning.

3. The perforating instrument according to claim 2, characterized in that, The battery at least includes two parts, and at least one part of the battery is arranged below the detonation disconnection section.

4. The perforating instrument according to any one of claims 1 to 3, characterized in that, It further includes: A fishing head is arranged on the upper part of the data return section for fishing the logging-while-perforating tool. A buoyancy chamber is arranged on the upper part of the electromagnetic deceleration section for reducing the descending speed of the logging-while-perforating tool in the wellbore and providing power for the logging-while-perforating tool to return to the surface.

5. The perforating instrument according to any one of claims 1 to 3, characterized in that, The perforating gun includes: a perforating gun body and a bridge plug setting section, where: The bridge plug setting section is arranged at the lower part of the perforating gun body for setting the bridge plug on the formation. The perforating gun body and the bridge plug setting section are made of a soluble alloy material.

6. The perforating instrument according to claim 5, wherein The bridge plug setting section includes: A gunpowder chamber: arranged at the bottom of the perforating gun for providing setting power, and a first pin is arranged inside. A release joint is arranged below the gunpowder chamber and is provided with a second pin, and the second pin is used to disconnect the bridge plug setting from the logging-while-perforating tool. The shear force at which the first pin breaks is less than the shear force at which the second pin breaks. A push cylinder is sleeved outside the gunpowder chamber and the release joint. A rubber cylinder is arranged below the push cylinder for plugging the wellbore. A fixing cone is arranged below the rubber cylinder for cooperating with the push cylinder to squeeze the rubber cylinder, and one end of the fixing cone facing the bottom of the well is conical. A slip is sleeved on the conical part of the fixing cone for plugging the wellbore.

7. The perforating instrument according to claim 6, wherein, The bridge plug setting section further includes: Elastic claws are arranged inside the rubber cylinder, and one end facing the bottom of the well is a claw structure, and the claw structure is used to cooperate with the card slot of the fixing cone to fix the rubber cylinder after setting.

8. A perforating method applied to the perforator based on cable-free connection according to any one of claims 1 to 7, characterized in that, It includes: The magnetic positioning section and the gyroscope of the logging-while-perforating tool perform positioning on the logging-while-perforating tool according to the pre-acquired wellbore structure data so that the current depth of the logging-while-perforating tool is a preset perforation depth. The perforating gun of the logging-while-perforating tool perforates the layer corresponding to the perforation depth. The detonation disconnection section of the logging-while-perforating tool reduces the weight of the logging-while-perforating tool. The power section on the logging-while-perforating tool provides thrust to make the logging-while-perforating tool return to the surface, and the logging-while-perforating tool stores the downhole-collected perforation operation data.

9. The perforating method according to claim 8, wherein The magnetic positioning part and the gyroscope of the perforator locate the perforator according to the pre-acquired wellbore structure data, so that the current depth of the perforator is the preset perforation depth, including: Performing a primary positioning of the perforator according to the wellbore structure data and the magnetic positioning part of the perforator; The magnetic positioning part of the perforator performs a primary positioning of the perforator according to the wellbore structure data; The gyroscope determines the current descending speed of the perforator; The magnetic positioning part performs a secondary positioning of the perforator according to the current descending speed, so that the current depth is the perforation depth.

10. The perforating method according to claim 8, characterized in that, The detonating disconnecting part of the perforator reduces the weight of the perforator, including: The detonating disconnecting part detonates the pyrotechnic release in it and causes it to break, so that the detonating disconnecting part and the components below it are separated from the perforator.

11. The perforation method according to claim 8, wherein, Before the magnetic positioning part and the gyroscope of the perforator locate the perforator according to the pre-acquired wellbore structure data, so that the current depth of the perforator is the preset perforation depth, it further includes: The power part and the buoyancy chamber of the perforator control the descending speed of the perforator in the wellbore; After the detonating disconnecting part of the perforator reduces the weight of the perforator, it further includes: The buoyancy chamber provides buoyancy to make the perforator return to the ground.

12. The perforation method according to claim 8, wherein, Before the perforating gun of the perforator perforates the formation corresponding to the perforation depth, it further includes: The electromagnetic deceleration part of the perforator controls the magnetic force between the perforator and the casing, so that the perforator is located on the central axis of the casing; After the perforating gun of the perforator perforates the formation corresponding to the perforation depth, it further includes: The electromagnetic deceleration part eliminates the magnetic force.

13. The perforating method according to any one of claims 8 to 12, characterized in that, The perforator includes at least two electromagnetic deceleration parts, which are respectively located at the top and the top of the perforator; the perforating method further includes: When the perforating interval is a horizontal well section, the two electromagnetic deceleration parts adjust the magnetic force received by the perforator in the casing, so that the perforator is located on the central axis of the casing.

14. The perforating method according to any one of claims 8 to 12, characterized in that, Before the perforating gun of the perforator perforates the formation corresponding to the perforation depth, it further includes: The bridge plug setting part at the bottom of the perforator sets the bridge plug for the wellbore.

15. The perforating method according to claim 14, wherein, The bridge plug setting part at the bottom of the perforator sets the bridge plug for the wellbore, including: The bridge plug setting ignites the gunpowder inside the gunpowder chamber, causes the first pin inside the gunpowder chamber to break, and generates a thrust to push the push cylinder towards the fixed cone direction, so as to squeeze the rubber cylinder between the push cylinder and the fixed cone, and make the rubber cylinder set the bridge plug for the wellbore; One end of the fixed cone with a conical shape enters into the slips through the thrust, so as to make the slips set the bridge plug for the wellbore; The second pin in the release inside the lower part of the gunpowder chamber breaks through the thrust, so that the bridge plug setting is separated from the perforator, wherein the shearing force for the first pin to break is less than the shearing force for the second pin to break.

16. The perforating method according to claim 15, characterized in that, The bridge plug setting part at the bottom of the perforator sets the bridge plug for the wellbore, and further includes: The elastic claws inside the rubber cylinder are stuck on the card slots of the fixed cone through the thrust to fix the rubber cylinder after setting the bridge plug, wherein the perforating gun and the bridge plug setting part are made of a soluble alloy material.

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