Anti-blocking separate injection tubular column and separate injection method

Abstract

The invention relates to an anti-blocking separate injection tubular column and a separate injection method. The tubular column comprises a first packer, a second packer, a third packer, a plurality of measure switch tools, a fourth packer and a ball seat which are connected through an oil pipe. The first packer is arranged above the second packer; measure switch tools are arranged between the second packer and the third packer, between the third packer and the fourth packer and between the fourth packer and the ball seat; the ball seat is arranged at the lower end of the column. A plurality of oil layers can be separated by the first packer, the second packer, the third packer and the fourth packer, water is injected into the separated corresponding oil layers by means of each measure switch tool, and safe and effective layered water injection of the deep inclined shaft of the corroded and scaled well of the oil field is achieved. The tubular column is an anti-blocking soft anchoring separate injection tubular column in a well washing unblocking mode, the load is not increased during unblocking of the tubular column, the hidden danger that the separate injection tubular column is prone to scaling and hard blocking is eliminated, and the risk probability of overhaul caused by corrosion, scaling, hard blocking and the like is reduced.

Description

Technical Field

[0001] The invention relates to an anti-sticking injection pipe column and an injection method. Background Art

[0002] Metal slip anchoring tools are required in the injection string for deep inclined wells, high temperature and high pressure wells and other complex well conditions to prevent the injection string from creeping and failing under various mechanical effects; however, due to factors such as high pressure, corrosion and scaling, the injection string has problems such as large unblocking load, easy scaling and hard sticking causing overhaul, and casing damage. Summary of the invention

[0003] In order to enrich the types of injection strings in the prior art, eliminate the hidden danger of easy scaling and hard sticking of injection strings, and realize safe and effective water injection in deep and inclined wells with corrosion and scaling in oil fields, the present invention proposes an anti-sticking injection string and an injection method. The technical solution proposed by the present invention is as follows:

[0004] In a first aspect, the present invention provides an anti-sticking injection string, comprising: a first packer connected by a tubing, at least one second packer, a third packer, a plurality of measure switch tools, at least one fourth packer and a ball seat;

[0005] The first packer is arranged above the second packer;

[0006] The measure switch tool is arranged between the second packer and the third packer, between the third packer and the fourth packer, and between the fourth packer and the ball seat;

[0007] The ball seat is arranged at the lower end of the pipe column;

[0008] In the ball seat blocking state, the expansion rubber tubes of the first packer, the second packer, the third packer and the fourth packer can be expanded and sealed on the casing under the hydraulic pressure of the liquid in the oil pipe to separate multiple oil layers; each of the switch tools is used to inject water into the corresponding oil layer;

[0009] The first packer can be depressurized and unsealed;

[0010] The second packer can be unsealed under the hydraulic action of the well-washing fluid injected into the annulus of the casing during the well-washing process;

[0011] The third packer can be unsealed by lifting the pipe string or can be unsealed under the hydraulic pressure of the well washing fluid in the casing annulus during the well washing process;

[0012] The fourth packer can be lifted up to release the pipe string.

[0013] In some embodiments, if the number of oil layer layers is greater than three, the number of the first packer, the second packer, the third packer and / or the fourth packer is two or more, and the measure switch tool is arranged between two adjacent packers.

[0014] In some embodiments, the second packer includes a second packer body, a second rubber tube inner bag space, a second expansion rubber tube, a first seat sealing anti-spitting valve ball, a well washing and unsealing moving body and a constant pressure unsealing spring;

[0015] The second packer body and the second expansion rubber tube form an inner capsule space of the second rubber tube;

[0016] The second packer body is provided with a second packing fluid inlet hole, a well washing fluid inlet channel, a balance channel, an unpacking fluid outlet hole and an unpacking hole expansion section;

[0017] The first seat seal anti-backspitting valve ball is arranged in the second seat seal liquid inlet hole;

[0018] The well-washing and unsealing moving body and the unsealing and expanding hole section are both arranged in the well-washing liquid inlet channel;

[0019] The constant pressure unsealing spring is arranged on the outer wall of the well-washing unsealing moving body, the unsealing hole expansion section is arranged at the tail end of the well-washing unsealing moving body, and the width of the upper end of the unsealing hole expansion section is greater than the width of the tail end of the well-washing unsealing moving body;

[0020] The well-washing and unsealing moving body is provided with a pressure relief channel, and the pressure relief channel is communicated with the unsealing liquid outlet hole;

[0021] The upper end of the balancing channel is closed, and the lower end of the balancing channel is communicated with the unsealing and expanding hole section.

[0022] In some embodiments, the second expansion rubber tube includes a second outer rubber, a second reinforcing rib and a second inner rubber;

[0023] The second reinforcing rib is arranged between the second outer rubber and the second inner rubber.

[0024] In some embodiments, the outer surface of the second outer rubber is wavy.

[0025] In some embodiments, the second reinforcing rib is a fiber wire, a stainless steel wire or a steel sheet.

[0026] In some embodiments, the fourth packer includes a fourth packer body, a fourth rubber tube inner capsule space, a fourth expansion rubber tube, a second seat sealing anti-spitting valve ball, an unsealing shear pin, a well flushing valve and a well flushing valve reset spring;

[0027] The fourth rubber tube inner capsule space is formed between the fourth packer body and the fourth expansion rubber tube;

[0028] The fourth packer body is connected to the fourth expansion rubber cylinder through the unpacking shear pin;

[0029] A fourth sealing liquid inlet hole is provided on one side of the fourth packer body, and a well washing channel is provided on the other side of the fourth packer body;

[0030] The second seat sealing anti-backspitting valve ball is arranged in the fourth seat sealing liquid inlet hole;

[0031] The well-washing valve and the well-washing valve return spring are arranged in the well-washing channel, and the first end of the well-washing valve return spring is connected to the well-washing valve, and the second end of the well-washing valve return spring is fixed to the bottom end of the well-washing channel.

[0032] In some embodiments, the fourth expansion rubber tube includes a fourth outer rubber, a fourth reinforcing rib and a fourth inner rubber;

[0033] The fourth reinforcing rib is arranged between the fourth outer rubber and the fourth inner rubber.

[0034] In some embodiments, the well washing channel includes a first channel and a second channel connected, and the width of the second channel is greater than the width of the first channel;

[0035] The well flushing valve and the well flushing valve return spring are arranged in the second channel, and the width of the well flushing valve is greater than the width of the first channel.

[0036] In some embodiments, the outer surface of the fourth outer rubber is wavy.

[0037] In some embodiments, the fourth reinforcing rib is a fiber wire, a stainless steel wire or a steel sheet.

[0038] In some embodiments, the first packer comprises a first packer body, a first rubber tube inner capsule space and a first expansion rubber tube;

[0039] The first rubber tube inner capsule space is formed between the first packer body and the first expansion rubber tube;

[0040] The first packer body is provided with a first sealing liquid inlet hole.

[0041] In some embodiments, the first expansion rubber tube includes a first outer rubber, a first reinforcing rib and a first inner rubber;

[0042] The first reinforcing rib is arranged between the first outer rubber and the first inner rubber.

[0043] In some embodiments, the outer surface of the first outer rubber is wavy.

[0044] In some embodiments, the first reinforcing rib is a fiber wire, a stainless steel wire or a steel sheet.

[0045] In some embodiments, the second packer includes an upper joint, a central pipe, a sealing shear pin, a sealing start piston, a first connecting piece, a second connecting piece, a sealing valve, a spring, a rubber sleeve upper joint, a rubber sleeve inner bag, a reinforcing rib, a rubber sleeve outer bag, a rubber sleeve lower joint, a bottom plug and a lower joint;

[0046] The upper joint is connected to the oil pipe, the center pipe and the first connecting piece respectively, the first connecting piece is connected to the second connecting piece, the seat seal start piston is arranged in the accommodation space formed by the first connecting piece and the center pipe, and the seat seal start piston is connected to the first connecting piece through the seat seal shear pin;

[0047] The sealing valve and the spring are arranged in the accommodation space formed by the second connecting piece and the central tube, one end of the spring is connected to the sealing valve, and the other end is connected to the second connecting piece;

[0048] A sealing member is provided on the side of the sealing valve opposite to the first connecting member, the lower end of the second connecting member is connected to the upper joint of the rubber tube, a reinforcing rib is provided between the inner capsule of the rubber tube and the outer capsule of the rubber tube, and the rear end of the reinforcing rib and the outer capsule of the rubber tube is connected to the lower joint of the rubber tube;

[0049] The bottom plug and the lower joint are both connected to the central tube, arranged outside the central tube, and connected to the lower joint of the rubber tube. The central tube is provided with a first liquid inlet hole at a position corresponding to the first connecting piece;

[0050] A cavity is formed between the upper joint and the seat seal starting piston, and a second liquid inlet hole is provided at a position of the first connecting member corresponding to the cavity.

[0051] In some embodiments, the inner capsule spaces of the rubber sleeves of the first packer, the second packer, the third packer and the fourth packer are all pre-filled with rust inhibitor or engine oil.

[0052] In a second aspect, the present invention provides a dispensing method, which is implemented using the anti-stuck dispensing column as described in the first aspect, and the method comprises:

[0053] Lowering the anti-stuck injection string, so that the first packer, the second packer, the third packer and the fourth packer separate the multiple oil layers, and so that the switching tools of each measure are respectively located at the position corresponding to the oil layer;

[0054] The anti-sticking injection string is pressurized successively through the oil pipe to complete the well, so that the first packer, the second packer, the third packer and the fourth packer are sealed on the casing;

[0055] Start various switching tools to inject water into the multiple oil layers;

[0056] At preset intervals, the oil pipe is depressurized to release the first packer, a well-washing fluid is injected into the annulus of the oil casing to release the second packer, the tubing is lifted or a well-washing fluid is injected into the annulus of the oil casing to release the third packer, the tubing is lifted to release the fourth packer, and the well-washing fluid is returned to the wellhead through the oil pipe to complete the well washing;

[0057] Repeat the above steps of sealing, water injection, pressure relief, well washing and pipe lifting until oil production is completed. Based on the above technical solution, the beneficial effects of the present invention compared with the prior art are as follows:

[0058] The anti-stuck injection string provided by the present invention has an expansion rubber tube of the first packer, the second packer, the third packer and the fourth packer that can expand and attach to the casing under the action of hydraulic pressure, and the pipe string is fixed by the friction of the rubber tube without damaging the casing. Compared with the metal anchor shoe hard-stuck casing fixation in the prior art, the anchor shoe bites into the inner wall of the casing to a certain size to damage the casing. The anti-stuck injection string of the present invention is a soft anchor injection string, which causes less damage to the casing; in addition, the first packer, the second packer, the third packer and the fourth packer can separate multiple oil layers, and each measure switch tool is used to inject water into the separated corresponding oil layers, so as to realize safe and effective stratified water injection in the deep inclined well of the oil field corrosion and scaling. Moreover, the second packer is unsealed by the well washing unsealing method. The pipe string of the present invention is an anti-stuck "soft anchor" injection string of the well washing unsealing method. The unsealing of the pipe string does not increase the load, eliminates the hidden danger of scaling and hard sticking of the injection string, and reduces the risk probability of overhaul caused by corrosion, scaling and hard sticking.

[0059] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0060] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0062] Figure 1 It is a schematic diagram of the soft anchor anti-stuck injection pipe column before sealing provided by an embodiment of the present invention;

[0063] Figure 2Schematic diagram of a soft anchor anti-stuck injection string after well completion provided by an embodiment of the present invention;

[0064] Figure 3 It is a structural schematic diagram of a pressure relief and unsealing expandable packer provided in an embodiment of the present invention;

[0065] Figure 4 2 is a schematic structural diagram of a well-washing and unsealing expandable packer provided in an embodiment of the present invention;

[0066] Figure 5 is a structural schematic diagram of a lift-and-release expandable packer provided in an embodiment of the present invention;

[0067] Figure 6 It is a schematic diagram of the structure of the expansion rubber cylinder provided by an embodiment of the present invention;

[0068] Figure 7 The embodiment of the present invention provides Figure 6 A schematic diagram of the enlarged structure of the middle rubber cylinder A;

[0069] Figure 8 is a schematic structural diagram of a soft anchor packer provided by an embodiment of the present invention;

[0070] Fig. 9 yes Figure 8 An enlarged schematic diagram of the structure at A;

[0071] Fig.10 yes Figure 8 An enlarged schematic diagram of the structure at location B.

[0072] In the figure: 1, first packer; 2, second packer; 3, measure switch tool; 4, third packer; 5, fourth packer; 6, ball seat; 7, oil pipe; 8, casing;

[0073] 101, first packer body; 10101, first sealing liquid inlet hole; 102, first rubber tube inner capsule space; 103, first expansion rubber tube; 10301, first outer rubber; 10302, first reinforcing rib; 10303, first inner rubber;

[0074] 201, second packer body; 20101, second packer inlet hole; 20102, well washing liquid inlet channel; 20103, balance channel; 20104, unpacking liquid outlet hole; 20105, unpacking expansion section; 202, second rubber tube inner capsule space; 203, second expansion rubber tube; 20301, second outer rubber; 20302, second reinforcing rib; 20303, second inner rubber; 204, first packer anti-return valve ball; 205, well washing unpacking moving body; 20501, pressure relief channel; 206, constant pressure unpacking spring;

[0075] 501, the fourth packer body; 50101, the fourth packer inlet hole; 50102, the well washing channel; 502, the fourth rubber tube inner capsule space; 503, the fourth expansion rubber tube; 50301, the fourth outer rubber; 50302, the fourth reinforcing rib; 50303, the fourth inner rubber; 504, the second packer anti-spitting valve ball; 505, the unpacking shear nail; 506, the well washing valve; 507, the well washing valve reset spring;

[0076] 901, upper joint; 902, center tube; 90201, first liquid inlet hole; 903, seat seal shear pin; 904, seat seal start piston; 905, first connecting piece; 906, second connecting piece; 907, sealing valve; 90701, sealing piece; 908, spring; 909, upper joint of rubber cartridge; 910, inner capsule of rubber cartridge; 911, reinforcing rib; 912, outer capsule of rubber cartridge; 913, lower joint of rubber cartridge; 914, bottom plug; 915, lower joint; 916, second liquid inlet hole. DETAILED DESCRIPTION

[0077] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0078] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0079] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0080] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0081] Metal slip anchoring tools are required in the injection string for deep inclined wells, high temperature and high pressure wells and other complex well conditions to prevent the injection string from creeping and failing under various mechanical effects; however, due to factors such as high pressure, corrosion and scaling, the injection string has problems such as large unblocking load, easy scaling and hard sticking causing overhaul, and casing damage. For example, during the inspection of 11 wells in a factory, 5 wells (2 wells had an inspection cycle of more than 3 years) were overhauled, and the overhaul rate reached 45.5%.

[0082] The inventor found that the prior art, such as the invention patent No. ZL201410634711.4, discloses a downhole injection method and injection string, which is composed of an outer pipe assembly and an outer pipe assembly. The outer pipe assembly includes an oil pipe 72, a top water distributor 1, a diversion sleeve 85-2 of a diversion device 4, a bridge sleeve of a diversion joint of the diversion device 4, a hydraulic anchor 6, an upper packer 7, a connecting valve 8, a lower packer 10, a plug 12, a screen 13, and a wire plug 14, which are fixed from top to bottom. Among them, the hydraulic anchor 6 is anchored by a metal anchor tile, which has the risk of hard jamming. The invention patent with the patent number ZL 201821013160.X discloses a multi-stage injection process string, which includes an anchor, multiple groups of string units, a fixed ball seat, a screen and a wire plug. Each group of string units includes a packer, a straightener and a water distributor connected in series from top to bottom. The anchor is anchored by metal anchor shoes, which poses a risk of hard jamming. The above two types of injection strings cannot meet the expectations of the inventor. After further research and development, the inventor made the present invention. The purpose of the present invention is to address the technical problems of large lifting and unsealing load of metal anchor shoe tools in the injection string of deep inclined wells with corrosion and scaling, easy scaling and hard jamming, resulting in overhaul and damage to the casing 8, and to study the "soft anchoring and anti-jamming injection technology for deep inclined wells with corrosion and scaling" to solve the technical problem of "safe and effective injection in deep inclined wells with corrosion and scaling".

[0083] Embodiment 1

[0084] The embodiment of the present invention provides an anti-stuck injection column, referring to Figure 1 As shown, it includes: a first packer 1, a second packer 2, a third packer 4, a plurality of measures switch tools 3, a fourth packer 5 and a ball seat 6 connected by a tubing 7;

[0085] The first packer 1 is arranged above the second packer 2;

[0086] The measure switch tool 3 is arranged between the second packer 2 and the third packer 4, between the third packer 4 and the fourth packer 5, and between the fourth packer 5 and the ball seat 6; each measure switch tool 3 is used to inject water into the corresponding oil layer; the ball seat 6 is arranged at the lower end of the tubing string; when the tubing string is lowered, the second packer 2, the third packer 4, and the fourth packer 5 are located between two adjacent oil layers, and each measure switch tool 3 is located at a position corresponding to the oil layer.

[0087] Reference Figure 2 As shown, in the sealed state of the ball seat 6, the expansion rubber tubes of the first packer 1, the second packer 2, the third packer 4 and the fourth packer 5 can all be expanded and sealed on the casing 8 under the hydraulic action of the liquid in the oil pipe 7 to separate multiple oil layers; when the pipe string is divided below, each of the above-mentioned packers is located between two adjacent oil layers to separate each oil layer, and the measure switch tool 3 is located at the position of each oil layer. When each packer is sealed, water is injected into the corresponding oil layer through the measure switch tool 3, so as to realize safe and effective stratified water injection in deep inclined wells with corrosion and scaling in oil fields.

[0088] The first packer 1 is a pressure relief and unsealing expansion packer, which can be unsealed by pressure relief;

[0089] The second packer 2 is a well-washing and unsealing expansion packer, which can be unsealed under the hydraulic action of the well-washing fluid injected into the annulus of the casing during the well-washing process;

[0090] The third packer 4 is a lift-up unsealing expansion packer or a well-washing unsealing expansion packer, which can be lifted up to unseale the pipe string or can be unsealed under the hydraulic pressure of the well-washing fluid in the casing annulus during the well-washing process;

[0091] The fourth packer 5 is a lift-up and unsealing expandable packer, which can lift the pipe string to unseale it.

[0092] The number and combination of the first packer 1, the second packer 2, the third packer 4, and the fourth packer 5 in the above-mentioned anti-stuck injection string are set according to the number of oil layers to be separated, and the number of the measure switch tools 3 is consistent with the number of separated oil layers. Taking the number of oil layers to be separated as an example, the anti-stuck injection string is composed of the first packer 1, the second packer 2, the measure switch tool 3, the third packer 4, the measure switch tool 3, the fourth packer 5, the measure switch tool 3 and the ball seat 6 fixedly connected by the oil pipe 7 from top to bottom. The second packer 2 is located above the upper oil layer, the third packer 4 is located between the upper oil layer and the middle oil layer, and the fourth packer 5 is located between the middle oil layer and the lower oil layer. The three measure switch tools 3 are respectively set at the positions corresponding to the upper oil layer, the middle oil layer and the lower oil layer, and the three measure switch tools 3 are used to inject water into the upper oil layer, the middle oil layer and the lower oil layer respectively.

[0093] The anti-stuck injection string provided by the present invention has expansion rubber tubes of the first packer 1, the second packer 2, the third packer 4 and the fourth packer 5 that can be expanded and attached to the casing 8 under the action of hydraulic pressure, and the pipe string is fixed by the friction force of the rubber tube without damaging the casing 8. Compared with the metal anchor shoe hard-carded casing 8 fixed in the prior art, the anchor shoe bites into the inner wall of the casing 8 to a certain size and damages the casing 8. The anti-stuck injection string of the present invention is a soft-anchored injection string, which causes little damage to the casing 8; in addition, the first packer 1, the second packer 2, the third packer 4 and the fourth packer 5 separate multiple oil layers, and each measure switch tool is used to inject water into the corresponding oil layer, thereby realizing safe and effective stratified water injection in deep and inclined wells with corrosion and scaling in oil fields. In order to solve the technical problems that the lifting and unsealing load of metal anchor tools in the deep inclined well injection string due to corrosion and scaling is large, scaling and sticking are easy to cause major repairs and damage the casing 8, the present invention studies the "soft anchoring and anti-sticking injection technology for deep inclined wells due to corrosion and scaling", and develops a well washing and unsealing expandable sealer, namely the second sealer 2, which is unsealed by the well washing and unsealing method. The pipe string of the present invention is an anti-sticking "soft anchoring" injection pipe string in the well washing and unsealing method. The unsealing of the pipe string does not increase the load, eliminates the hidden danger of major repairs caused by scaling and sticking of the injection pipe string, reduces the risk probability of major repairs caused by corrosion, scaling and sticking, etc., realizes safe and effective water injection in deep inclined wells due to corrosion and scaling in oil fields, and provides strong technical support for stable production in old areas.

[0094] In a specific embodiment, if the number of oil layer layers is greater than three, the number of the first packer 1, the second packer 2, the third packer 4 and / or the fourth packer 5 is two or more, and the measure switch tool 3 is set between two adjacent packers. The combination of the pipe string is set according to the number of oil layer layers. For example, when the number of oil layers is four, a lifting and unsealing expansion packer, i.e., the fourth packer 5, can be connected below the fourth packer 5, and the ball seat 6 is connected below the next fourth packer 5. The measure switch tool 3 is set between the two fourth packers 5 for water injection into the fourth oil layer. A well-washing and unsealing expansion packer, i.e., the second packer 2, can also be connected below the fourth packer 5, and the measure switch tool 3 is set between the fourth packer 5 and the second packer 2 below.

[0095] In a specific embodiment, the first packer 1 may be a pressure relief expansion packer; Figure 3 As shown, the first packer 1 comprises a first packer body 101, a first rubber tube inner capsule space 102 and a first expansion rubber tube 103;

[0096] The first rubber tube inner capsule space 102 is formed between the first packer body 101 and the first expansion rubber tube 103;

[0097] The first packer body 101 is provided with a first packer liquid inlet hole 10101 .

[0098] In a specific embodiment, referring to Figure 6 As shown, the first expansion rubber tube 103 includes a first outer rubber 10301, a first reinforcing rib 10302 and a first inner rubber 10303;

[0099] The first reinforcing rib 10302 is disposed between the first outer rubber 10301 and the first inner rubber 10303 .

[0100] In a specific embodiment, referring to Figure 7 As shown, the outer surface of the first outer rubber 10301 is wavy. The outer rubber surface of the expansion rubber tube adopts a wavy micro rubber tube, which has a large contact area with the sleeve 8 and a large anchoring force.

[0101] In a specific embodiment, the first reinforcing rib 10302 is a fiber wire, a stainless steel wire or a steel sheet.

[0102] In a specific embodiment, the second packer 2 may be a well-washing and unsealing expansion packer; Figure 4 As shown, the second packer 2 comprises a second packer body 201, a second rubber tube inner capsule space 202, a second expansion rubber tube 203, a first seat sealing anti-spitting valve ball 204, a well washing and unsealing moving body 205 and a constant pressure unsealing spring 206;

[0103] The second packer body 201 and the second expansion rubber tube 203 form the second rubber tube inner capsule space 202;

[0104] The second packer body 201 is provided with a second packing fluid inlet hole 20101, a well washing fluid inlet channel 20102, a balance channel 20103, an unpacking fluid outlet hole 20104 and an unpacking hole expansion section 20105;

[0105] The first seat-sealed anti-back-spitting valve ball 204 is arranged in the second seat-sealed liquid inlet hole 20101; the first seat-sealed anti-back-spitting valve ball 204 can seal the second seat-sealed liquid inlet hole 20101 after the liquid enters the second rubber cylinder inner capsule space 202, so that the second expansion rubber cylinder 203 is seat-sealed on the sleeve 8.

[0106] The well-washing and unsealing moving body 205 and the unsealing and expanding hole section 20105 are both arranged in the well-washing liquid inlet channel 20102;

[0107] The constant pressure unsealing spring 206 is arranged on the outer wall of the well-washing unsealing moving body 205, the unsealing reaming section 20105 is arranged at the tail end of the well-washing unsealing moving body 205, and the width of the upper end of the unsealing reaming section 20105 is greater than the width of the tail end of the well-washing unsealing moving body 205;

[0108] The well-washing and unsealing moving body 205 is provided with a pressure relief channel 20501, and the pressure relief channel 20501 is communicated with the unsealing liquid outlet 20104;

[0109] The upper end of the balance channel 20103 is closed, and the lower end of the balance channel 20103 is connected to the unsealing and expanding section 20105. When the well-washing and unsealing moving body 205 moves downward, the balance channel 20103 can prevent vacuum from forming in the unsealing and expanding section 20105.

[0110] During the well washing process, the well washing unsealing moving body 205 can compress the constant pressure unsealing spring 206 and move downward relative to the unsealing expansion section 20105 when the pressure of the well washing fluid entering the well washing fluid inlet channel 20102 reaches the preset pressure, and the pressure relief channel 20501 is connected with the unsealing expansion section 20105, and the liquid in the second rubber cylinder inner capsule space 202 flows into the unsealing expansion section 20105 through the unsealing fluid outlet hole 20104, the second expansion rubber cylinder 203 is unsealed and retracted, the second seal 2 is unsealed, and the well washing fluid returns to the wellhead from the casing annulus through the oil pipe 7 to complete the well washing.

[0111] In a specific embodiment, referring to Figure 6 As shown, the second expansion rubber tube 203 includes a second outer rubber 20301, a second reinforcing rib 20302 and a second inner rubber 20303;

[0112] The second reinforcing rib 20302 is disposed between the second outer rubber 20301 and the second inner rubber 20303. By disposing the reinforcing rib between the second outer rubber 20301 and the second inner rubber 20303, the strength and rigidity of the second outer rubber 20301 and the second inner rubber 20303 are improved.

[0113] In a specific embodiment, referring to Figure 7 As shown, the outer surface of the second outer rubber 20301 is wavy. The outer rubber surface of the expansion rubber tube adopts a wavy micro rubber tube, which has a large contact area with the sleeve 8 and a large anchoring force.

[0114] In a specific embodiment, the second reinforcing ribs 20302 are fiber filaments, stainless steel wires or steel sheets. Compared with pure rubber-type rubber sleeves, the rubber sleeve structure composed of reinforcing ribs made of fiber filaments, stainless steel wires or steel sheets has a higher pressure bearing capacity.

[0115] In a specific embodiment, the fourth packer 5 may be a lift-up and unseal expandable packer; Figure 5 As shown, the fourth packer includes a fourth packer body 501, a fourth rubber tube inner capsule space 502, a fourth expansion rubber tube 503, a second seat sealing anti-spitting valve ball 504, an unsealing shear pin 505, a well washing valve 506 and a well washing valve reset spring 507;

[0116] The fourth packer body 501 and the fourth expansion rubber tube 503 form the fourth rubber tube inner capsule space 502;

[0117] The fourth packer body 501 is connected to the fourth expansion rubber cylinder 503 through the unpacking shear pin 505;

[0118] A fourth packer fluid inlet hole 50101 is provided on one side of the fourth packer body 501, and a well washing channel 50102 is provided on the other side of the fourth packer body 501;

[0119] The second seat-sealing anti-back-spitting valve ball 504 is arranged in the fourth seat-sealing liquid inlet hole 50101; the second seat-sealing anti-back-spitting valve ball 504 can seal the fourth seat-sealing liquid inlet hole 50101 after the liquid enters the fourth rubber cylinder inner capsule space 502, so that the fourth expansion rubber cylinder 503 is seat-sealed on the sleeve 8.

[0120] The well-washing valve 506 and the well-washing valve return spring 507 are arranged in the well-washing channel 50102, and the first end of the well-washing valve return spring 507 is connected to the well-washing valve 506, and the second end of the well-washing valve return spring 507 is fixed to the bottom end of the well-washing channel 50102. The well-washing channel 50102 is a channel that is narrow at the top and wide at the bottom, and the well-washing valve 506 and the well-washing valve return spring 507 are arranged in the area below the channel. When washing the well, the well-washing fluid enters from the well-washing channel 50102, and when it flows to the well-washing valve return spring 507, the well-washing valve return spring 507 is compressed, and the well-washing valve 506 washes the well-washing channel, and the cleaning fluid flows into the casing annulus through the lower end of the well-washing channel 50102 and returns to the wellhead through the oil pipe 7.

[0121] In a specific embodiment, referring to Figure 6 As shown, the fourth expansion rubber tube 503 includes a fourth outer rubber 50301, a fourth reinforcing rib 50302 and a fourth inner rubber 50303;

[0122] The fourth reinforcing rib 50302 is disposed between the fourth outer rubber 50301 and the fourth inner rubber 50303 .

[0123] In a specific embodiment, the well washing channel 50102 includes a first channel and a second channel connected, and the width of the second channel is greater than the width of the first channel;

[0124] The well flushing valve 506 and the well flushing valve return spring 507 are disposed in the second passage, and the width of the well flushing valve 506 is greater than the width of the first passage.

[0125] In a specific embodiment, referring to Figure 2 and Figure 7 As shown, the outer surface of the fourth outer rubber 50301 is wavy. Anchoring force F = μF N , where F N is the positive pressure, μ is the friction coefficient between the expansion rubber tube and the sleeve 8, and the anchoring force F is the friction force between the expansion rubber tube and the sleeve 8 generated by the pressure in the inner capsule space of the rubber tube pushing the expansion rubber tube to be close to the sleeve 8. Indoor tests show that the water injection pressure is proportional to the anchoring force. When the water injection pressure is 20MPa, the anchoring force is 35t, and when the water injection pressure is 30MPa, the anchoring force is 48t. The outer rubber surface of the expansion rubber tube adopts a wavy micro rubber tube, which has a large contact area with the sleeve 8 and a large anchoring force.

[0126] In a specific embodiment, the fourth reinforcing rib 50302 is a fiber wire, a stainless steel wire or a steel sheet.

[0127] In a specific embodiment, the inner capsule spaces of the rubber tubes of the first packer, the second packer, the third packer and the fourth packer are pre-filled with rust preventer or engine oil. By pre-filling with rust preventer or engine oil, the expansion rubber tube can be prevented from rusting and the service life of the expansion rubber tube can be increased.

[0128] In the embodiment of the present invention, the expansion rubber tube of each packer has a preset length, and the length of the expansion rubber tube is set according to the working pressure, which is not specifically limited in the present invention. The expansion rubber tube has a large length, a large contact area with the casing 8, and a correspondingly large friction force, so that the expansion rubber tube can be tightly attached to the casing 8.

[0129] The sealing process of the first packer 1, the second packer 2, the third packer 4 and the fourth packer 5 is as follows:

[0130] Configure the injection string, lower the injection string to the designed position, and throw a ball into the tubing 7 so that the ball is stuck on the ball seat 6. The tubing 7 is pressurized to complete the well in sequence, generally at 5MPa, 10MPa, 15MPa, and 20MPa, and the pressure is stabilized for 3 minutes each time. After the liquid enters the tubing 7 and increases the pressure, the expansion rubber cylinders of the first packer 1, the second packer 2, the third packer 4, and the fourth packer 5 expand under the action of hydraulic pressure and tightly adhere to the casing 8, and the seat seal is achieved in sequence. The specific process is as follows:

[0131] After the liquid enters the oil pipe 7 and is pressurized, the liquid enters the first rubber cylinder inner capsule space 102 from the first sealed liquid inlet hole 10101. The pressure of the oil pipe 7 drives the first expansion rubber cylinder 103 to expand and tightly adhere to the sleeve 8.

[0132] After the liquid enters the oil pipe 7 and is pressurized, the liquid enters the second rubber cylinder inner capsule space 202 from the second seal liquid inlet hole 20101. The pressure of the oil pipe 7 drives the second expansion rubber cylinder 203 to expand and tightly adhere to the sleeve 8.

[0133] After the liquid enters the oil pipe 7 and is pressurized, the liquid enters the inner bag space of the third rubber cylinder (not shown in the figure) from the third seat sealing liquid hole of the third packer (not shown in the figure). The pressure of the oil pipe 7 drives the third expansion rubber cylinder (not shown in the figure) to expand and tightly adhere to the casing 8.

[0134] After the liquid enters the oil pipe 7 and is pressurized, the liquid enters the fourth rubber cylinder inner capsule space 502 from the fourth seat seal liquid inlet hole 50101. The pressure of the oil pipe 7 drives the fourth expansion rubber cylinder 503 to expand and tightly adhere to the sleeve 8.

[0135] The structure of the third packer 4 is the same as that of the second packer 2 or the fourth packer 5. Figure 4 or Figure 5 shown.

[0136] The force -F1 generated by the second packer 2 and the force +F1 generated by the third packer 4, and the force F generated by the third packer 4 and the fourth packer 5 are in opposite directions, offsetting each other, and the force on the pipe string is balanced. The annulus pressure P3 of the fourth packer 5 is subjected to force F3 in the upward direction, and the force F3 on the pipe string is in the upward direction. Therefore, in the injection pipe string, the change in force caused by the change in pipe string pressure is mainly caused by the bottom packer, i.e., the fourth packer 5, and the force on the pipe string mainly considers the force on the fourth packer 5. Each packer in the present invention is an expansion packer. Theoretically, the force generated by two sets of expansion packers is 36t, and the force generated by the bottom packer under the working condition of 30MPa is 0.25*π*124^2*30=36(t). The two sets of expansion packers can meet the working environment of 30MPa. The above 124 is the inner diameter of the casing of the packer, and each force refers to the pressure difference between the inside and outside of the packer. P is the pressure in the oil pipe, and P1, P2, and P3 are the pressures of each oil layer respectively.

[0137] When the number of oil layers to be isolated is two, the composition schemes of the injection string in the 30MPa working environment are as follows:

[0138] Solution 1: A string consisting of a pressure relief and unsealing expandable packer, i.e., the first packer 1, and a well washing and unsealing expandable packer, i.e., the second packer 2, or a string consisting of a pressure relief and unsealing expandable packer, i.e., the first packer 1, and a lifting and unsealing expandable packer, i.e., the fourth packer 5, is suitable for a bottom packer to be less than 100m away from the top packer.

[0139] Solution 2: A string consisting of a well-washing and unsealing expandable packer, i.e., the second packer 2, and a lifting and unsealing expandable packer, i.e., the fourth packer 5, is suitable for a situation where the distance between the bottom packer and the top packer is greater than 100m.

[0140] The sealing process of the first packer 1, the second packer 2, the third packer 4 and the fourth packer 5 is as follows:

[0141] The first packer 1 is a pressure-releasing expansion packer. After the pressure injection into the oil pipe 7 stops, the first packer 1 is released.

[0142] The second packer 2 is a well-washing and unsealing expansion packer, refer to Figure 4 As shown, the unsealing process of the second packer 2 is: injecting well washing fluid into the casing annulus, pressurizing the casing annulus, and transmitting the annular pressure to the well washing liquid inlet channel 20102. The pressure pushes the well washing unsealing moving body 205 to compress the constant pressure unsealing spring 206 and move downward to the pressure relief channel 20501 to connect with the unsealing expansion section 20105. The liquid in the inner capsule space 202 of the second rubber cylinder is released into the casing annulus through the unsealing liquid outlet hole 20104, the pressure relief channel 20501, and the unsealing expansion section 20105, and the second packer 2 is unsealed.

[0143] The fourth packer 5 is a lifting and unsealing expansion packer, refer to Figure 5 As shown, the unsealing process of the fourth packer 5 is: lifting the tubing string to pull off the unsealing shear nail 505, after the unsealing shear nail 505 is cut off, the fourth expansion rubber cylinder 503 moves downward, the liquid in the capsule space 502 of the fourth rubber cylinder is depressurized into the oil casing annulus, and the fourth packer 5 is unsealed.

[0144] The structure of the third packer 4 is the same as that of the second packer 2 or the fourth packer 5 , and the unsealing process thereof can refer to the description of the unsealing process of the second packer 2 or the fourth packer 5 mentioned above.

[0145] Reference Figure 8 , Fig. 9 and Fig.10 As shown, the present invention also provides a structure of a second packer 2, which is also a soft anchor packer, and the sealing is achieved by expanding the rubber tube, and the unsealing is achieved by washing the well. The second packer 2 includes an upper joint 901, a central tube 902, a sealing shear nail 903, a sealing start piston 904, a first connecting piece 905, a second connecting piece 906, a sealing valve 907, a spring 908, a rubber tube upper joint 909, a rubber tube inner capsule 910, a reinforcing rib 911, a rubber tube outer capsule 912, a rubber tube lower joint 913, a bottom plug 914, and a lower joint 915; wherein, the rubber tube inner capsule 910 functions to seal the space between the central tube 902 and the rubber tube inner capsule 10 to form a sealing pressure, and the rubber tube outer capsule 912 is used to seal the casing annulus after the packer is sealed in the casing.

[0146] The upper joint 901 is connected to the oil pipe 7, the center pipe 902 and the first connecting piece 905 respectively, the first connecting piece 905 is connected to the second connecting piece 906, the seat seal start piston 904 is arranged in the accommodation space formed by the first connecting piece 905 and the center pipe 902, and the seat seal start piston 904 is connected to the first connecting piece 905 through the seat seal shear pin 903;

[0147] The sealing valve 907 and the spring 908 are arranged in the accommodation space formed by the second connecting member 906 and the central tube. One end of the spring 908 is connected to the sealing valve 907, and the other end is connected to the second connecting member 906.

[0148] A sealing member 90701 is provided on the side of the sealing valve 907 opposite to the first connecting member 905, the lower end of the second connecting member 906 is connected to the upper joint 909 of the rubber tube, a reinforcing rib 911 is provided between the inner capsule 910 of the rubber tube and the outer capsule 912 of the rubber tube, and the rear ends of the reinforcing rib 911 and the outer capsule 912 of the rubber tube are connected to the lower joint 913 of the rubber tube;

[0149] The bottom plug 914 and the lower joint 915 are both connected to the central tube 902, arranged outside the central tube 902, and connected to the lower joint 913 of the rubber tube. The central tube 902 is provided with a first liquid inlet hole 90201 at a position corresponding to the first connecting piece 905;

[0150] A cavity is formed between the upper joint 901 and the seat seal starting piston 904 , and a second liquid inlet hole 916 is provided at a position of the first connecting member 905 corresponding to the cavity.

[0151] The sealing process is as follows: the oil supply pipe 7 is pressurized, the liquid enters the central tube 902, the liquid in the central tube 902 is transmitted to the first liquid inlet hole 90201, the sealing shear pin 903 is sheared by force, and the hydraulic pressure pushes the sealing start piston 904 to move to the left. At the same time, the liquid Figure 8 The liquid flows rightward in the direction indicated by the middle arrow, passes through the spring 908 and enters the inner capsule 910 of the rubber cartridge. The sealing member 90701 of the sealing valve 907 forms a seal with the first connecting member 905 under the push of the spring 908. The sealing member 90701 fills the space at the upper end of the first connecting member 905. The liquid in the inner capsule 910 of the rubber cartridge cannot flow out. The inner capsule 910 of the rubber cartridge and the outer capsule 912 of the rubber cartridge are sealed on the sleeve 8.

[0152] The unsealing process is as follows: the oil pipe is depressurized, and the annulus of the oil casing is pressurized. There is no plug between the upper joint 901 and the first connecting piece 905, and the liquid enters from the second liquid inlet hole 916. The sealing start piston 904 pushes the sealing valve 907 to move rightward, and the seal between the sealing piece 90701 and the first connecting piece 905 is released to leave a gap, and the high-pressure liquid in the inner capsule 910 of the rubber cylinder flows out and flows into the central pipe 902 through the first liquid inlet hole 90201. The outer capsule 912 of the rubber cylinder is depressurized and retracted, and the second packer 2 is unsealed. The oil pipe is pressurized again to achieve repeated sealing. In another embodiment, the upper joint 901 is threadedly connected to the first connecting piece 905 and is connected in reverse. When unsealing, the upper joint 901 and the first connecting piece 905 can be separated by reversing the oil pipe, and the liquid enters from the upper end of the first connecting piece 905 to achieve unsealing.

[0153] Compared with conventional pipe strings, due to the presence of the pressure relief unsealing expansion packer, i.e., the first packer 1, the oil pipe 7 can be unsealed by pressure relief, and the unsealing load of the injection pipe string of the present invention is relatively low, generally about 16 tons lower, and has high safety. If the third packer 4 and the fourth packer 5 are both well-washing unsealing expansion packers, the unsealing load of the pipe string is zero.

[0154] Embodiment 2

[0155] The embodiment of the present invention provides a dispensing method, which is implemented by using the anti-stuck dispensing column as described in the first embodiment above, and the method includes:

[0156] Lowering the anti-stuck injection string, so that the first packer 1, the second packer 2, the third packer 4 and the fourth packer 5 separate the multiple oil layers, and each of the measure switch tools 3 is located at the position of the corresponding oil layer;

[0157] The well is completed by gradually pressurizing the anti-sticking injection string through the oil pipe 7, so that the first packer 1, the second packer 2, the third packer 4 and the fourth packer 5 are seated on the casing 8;

[0158] Turning on the switch tools 3 of each measure to inject water into the multiple oil layers in layers;

[0159] At preset intervals, the oil pipe 7 is depressurized to unseal the first packer 1, and the washing fluid is injected into the annulus of the casing to unseal the second packer 2. The tubing string is lifted or the washing fluid is injected into the annulus of the casing to unseal the third packer 4, and the tubing string is lifted to unseal the fourth packer 5. The washing fluid returns to the wellhead through the oil pipe 7 to complete the well washing. Well washing process: after the injection is stopped and the oil pipe 7 is depressurized, the pressure is released to unseal the expansion packer, that is, the first packer 1 is unsealed. When the casing 8 pressurized well washing pressure reaches the set pressure, the well washing unseals the expansion packer, that is, the second packer 2 is unsealed, and the washing fluid goes down and passes through the washing valve of the third packer 4 to the upper part of the fourth packer 5. The washing pressure pushes the washing valve 506 to move, and the washing fluid goes down to the ball seat 6 through the washing channel 50102, and returns to the wellhead through the oil pipe 7 to complete the well washing. After the well is cleaned, the measure switch tool 3 is closed, the oil pipe 7 is pressurized and sealed again, and the measure switch tool 3 is opened to continue to inject water into each oil layer in layers. The above-mentioned well cleaning process and layered water injection process are repeated at intervals of preset time until oil production is completed and the pipe string is pulled out.

[0160] The existing tools lift a certain load (about 12t) to break the shear nails and unseal the pipe string. The unsealing load of the pipe string is the sum of the original hanging weight of the pipe string and the unsealing load of the tool. The unsealing loads are superimposed when the tool is used in multiple stages. The first packer of the present invention is unsealed by pressure relief, the second packer is unsealed by well washing, and the third and fourth packers are unsealed by lifting the pipe string. Lifting the pipe string does not increase the load. The original hanging weight is unsealed, and it will not increase by attaching to the casing 8.

[0161] In the embodiment of the present invention, the injection method corresponds to the anti-stuck injection column described in the above embodiment 1. Its specific implementation process can refer to the process of using the anti-stuck injection column for stratified water injection in the above embodiment 1. The repeated parts will not be repeated here.

[0162] In this document, relational terms such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. The orientation or position relationship indicated by the terms "upper", "lower", etc. is based on the orientation or position relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0163] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict. The present invention is not limited to any single aspect, any single embodiment, or any combination and / or permutation of these aspects and / or embodiments. Each aspect and / or embodiment of the present invention can be used alone, or in combination with one or more other aspects and / or other embodiments.

[0164] Finally, it should be noted that the above-described embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed by the present invention, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. An anti-stuck injection column, characterized in that: include: A first packer (1), at least one second packer (2), a third packer (4), a plurality of measures switching tools (3), at least one fourth packer (5) and a ball seat (6) connected by an oil pipe; The first packer (1) is arranged above the second packer (2); The measure switch tool (3) is arranged between the second packer (2) and the third packer (4), between the third packer (4) and the fourth packer (5), and between the fourth packer (5) and the ball seat (6); The ball seat (6) is arranged at the lower end of the pipe column; When the ball seat (6) is blocked, the expansion rubber tubes of the first packer (1), the second packer (2), the third packer (4) and the fourth packer (5) can be expanded and sealed on the casing under the hydraulic pressure of the liquid in the oil pipe to separate multiple oil layers; each of the measure switch tools (3) is used to inject water into the corresponding oil layer; The first packer (1) can be depressurized and unsealed; The second packer (2) can be released under the hydraulic pressure of the well-washing fluid injected into the annulus of the casing during the well-washing process; The third packer (4) can be lifted up to release the seal by lifting the pipe string, or can be released under the hydraulic pressure of the well washing fluid in the annulus of the casing during the well washing process; The fourth packer (5) can be lifted up to release the pipe string.

2. The anti-stuck injection column according to claim 1, characterized in that: If the number of oil layer layers is greater than three, the number of the first packer (1), the second packer (2), the third packer (4) and / or the fourth packer (5) is two or more, and the measure switch tool (3) is arranged between two adjacent packers.

3. The anti-stuck injection column according to claim 1, characterized in that: The second packer (2) comprises a second packer body (201), a second rubber tube inner bag space (202), a second expansion rubber tube (203), a first seat sealing anti-spitting valve ball (204), a well-washing unsealing moving body (205) and a constant-pressure unsealing spring (206); The second packer body (201) and the second expansion rubber tube (203) form the second rubber tube inner capsule space (202); The second packer body (201) is provided with a second packing fluid inlet hole (20101), a well-washing fluid inlet channel (20102), a balance channel (20103), an unpacking fluid outlet hole (20104) and an unpacking hole expansion section (20105); The first seat seal anti-backspitting valve ball (204) is arranged in the second seat seal liquid inlet hole (20101); The well-washing and unsealing moving body (205) and the unsealing and expanding hole section (20105) are both arranged in the well-washing liquid inlet channel (20102); The constant pressure unsealing spring (206) is arranged on the outer wall of the well-washing unsealing moving body (205), the unsealing hole expansion section (20105) is arranged at the tail end of the well-washing unsealing moving body (205), and the width of the upper end of the unsealing hole expansion section (20105) is greater than the width of the tail end of the well-washing unsealing moving body (205); The well-washing and unsealing moving body (205) is provided with a pressure relief channel (20501), and the pressure relief channel (20501) is communicated with the unsealing liquid outlet hole (20104); The upper end of the balancing channel (20103) is closed, and the lower end of the balancing channel (20103) is connected to the unsealing and expanding hole section (20105).

4. The anti-stuck injection column according to claim 3, characterized in that: The second expansion rubber tube (203) comprises a second outer rubber skin (20301), a second reinforcing rib (20302) and a second inner rubber skin (20303); The second reinforcing rib (20302) is arranged between the second outer rubber (20301) and the second inner rubber (20303).

5. The anti-stuck injection column according to claim 4, characterized in that: The outer surface of the second outer rubber (20301) is wavy.

6. The anti-stuck injection column according to claim 4, characterized in that: The second reinforcing rib (20302) is fiber wire, stainless steel wire or steel sheet.

7. The anti-stuck injection column according to claim 1, characterized in that: The fourth packer comprises a fourth packer body (501), a fourth rubber tube inner capsule space (502), a fourth expansion rubber tube (503), a second seat sealing anti-spitting valve ball (504), an unsealing shear pin (505), a well flushing valve (506) and a well flushing valve reset spring (507); The fourth packer body (501) and the fourth expansion rubber cylinder (503) form the fourth rubber cylinder inner capsule space (502); The fourth packer body (501) is connected to the fourth expansion rubber cylinder (503) via the unpacking shear pin (505); A fourth sealing liquid inlet hole (50101) is provided on one side of the fourth packer body (501), and a well washing channel (50102) is provided on the other side of the fourth packer body (501); The second seat seal anti-backspitting valve ball (504) is arranged in the fourth seat seal liquid inlet hole (50101); The well washing valve (506) and the well washing valve return spring (507) are arranged in the well washing channel (50102), and the first end of the well washing valve return spring (507) is connected to the well washing valve (506), and the second end of the well washing valve return spring (507) is fixed to the bottom end of the well washing channel (50102).

8. The anti-stuck injection column according to claim 7, characterized in that: The fourth expansion rubber tube (503) comprises a fourth outer rubber (50301), a fourth reinforcing rib (50302) and a fourth inner rubber (50303); The fourth reinforcing rib (50302) is arranged between the fourth outer rubber (50301) and the fourth inner rubber (50303).

9. The anti-stuck injection column according to claim 8, characterized in that: The well washing channel (50102) comprises a first channel and a second channel connected to each other, wherein the width of the second channel is greater than the width of the first channel; The well flushing valve (506) and the well flushing valve return spring (507) are arranged in the second channel, and the width of the well flushing valve (506) is greater than the width of the first channel.

10. The anti-stuck injection column according to claim 8, characterized in that: The outer surface of the fourth outer rubber (50301) is wavy.

11. The anti-stuck injection column according to claim 8, characterized in that: The fourth reinforcing rib (50302) is fiber wire, stainless steel wire or steel sheet.

12. The anti-stuck injection column according to claim 1, characterized in that: The first packer (1) comprises a first packer body (101), a first rubber tube inner capsule space (102) and a first expansion rubber tube (103); The first rubber tube inner capsule space (102) is formed between the first packer body (101) and the first expansion rubber tube (103); The first packer body (101) is provided with a first packer liquid inlet hole (10101).

13. The anti-stuck injection column according to claim 12, characterized in that: The first expansion rubber tube (103) comprises a first outer rubber skin (10301), a first reinforcing rib (10302) and a first inner rubber skin (10303); The first reinforcing rib (10302) is arranged between the first outer rubber (10301) and the first inner rubber (10303).

14. The anti-stuck injection column according to claim 13, characterized in that: The outer surface of the first outer rubber (10301) is wavy.

15. The anti-stuck injection column according to claim 13, characterized in that: The first reinforcing rib (10302) is fiber wire, stainless steel wire or steel sheet.

16. The anti-stuck injection column according to claim 1, characterized in that: The second packer (2) comprises an upper joint (901), a central tube (902), a sealing shear pin (903), a sealing start piston (904), a first connecting piece (905), a second connecting piece (906), a sealing valve (907), a spring (908), a rubber sleeve upper joint (909), a rubber sleeve inner bag (910), a reinforcing rib (911), a rubber sleeve outer bag (912), a rubber sleeve lower joint (913), a bottom plug (914) and a lower joint (915); The upper joint (901) is respectively connected to the oil pipe (7), the center pipe (902) and the first connecting piece (905), the first connecting piece (905) is connected to the second connecting piece (906), the seat seal start piston (904) is arranged in the accommodation space formed by the first connecting piece (905) and the center pipe (902), and the seat seal start piston (904) is connected to the first connecting piece (905) through the seat seal shear pin (903); The sealing valve (907) and the spring (908) are arranged in a receiving space formed by the second connecting member (906) and the central tube (902), one end of the spring (908) is connected to the sealing valve (907), and the other end is connected to the second connecting member (906); A sealing member (90701) is provided on the side of the sealing valve (907) opposite to the first connecting member (905); the lower end of the second connecting member (906) is connected to the upper joint (909) of the rubber cartridge; a reinforcing rib (911) is provided between the inner capsule (910) of the rubber cartridge and the outer capsule (912) of the rubber cartridge; and the rear ends of the reinforcing rib (911) and the outer capsule (912) of the rubber cartridge are connected to the lower joint (913) of the rubber cartridge; The bottom plug (914) and the lower joint (915) are both connected to the central tube (902), arranged outside the central tube (902), and connected to the lower joint (913) of the rubber cylinder. The central tube (902) is provided with a first liquid inlet hole (90201) at a position corresponding to the first connecting piece (905); A cavity is formed between the upper joint (901) and the seat seal starting piston (904), and a second liquid inlet hole (916) is provided at a position of the first connecting member (905) corresponding to the cavity.

17. The anti-stuck injection column according to claim 1, characterized in that: The inner bag spaces of the rubber tubes of the first packer, the second packer, the third packer and the fourth packer are all pre-filled with rust preventive agent or engine oil.

18. A dispensing method, characterized in that: The method is implemented by using the anti-stuck injection column according to any one of claims 1 to 17, and the method comprises: Lowering the anti-sticking injection string, so that the first packer (1), the second packer (2), the third packer (4) and the fourth packer (5) separate the multiple oil layers, and each of the measure switch tools (3) is located at a position corresponding to the oil layer; The well is completed by gradually pressurizing the anti-sticking injection pipe string through the oil pipe, so that the first packer (1), the second packer (2), the third packer (4) and the fourth packer (5) are seated on the casing; Turning on various switching tools (3) to inject water into the multiple oil layers in layers; At preset intervals, the oil pipe is depressurized to release the first packer (1), a well-washing fluid is injected into the annulus of the oil casing to release the second packer (2), the pipe string is lifted or a well-washing fluid is injected into the annulus of the oil casing to release the third packer (4), the pipe string is lifted to release the fourth packer (5), and the well-washing fluid is returned to the wellhead through the oil pipe to complete the well washing; Repeat the above steps of sealing, water injection, pressure relief, well washing and lifting the tubing string until oil production is completed.

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