Separated layer water injection device

Abstract

The invention discloses a layered water injection device, and belongs to the technical field of oilfield exploitation equipment. Comprising an upper connector short section, a bypass short section, a sealing ball, a sealing ball seat, a gap bridge short section, a blind plug short section, a gap bridge outer cylinder and a lower connector short section which are sequentially connected. A first water injection hole is formed in the bypass short section; the sealing ball seat is arranged between the bypass short section and the upper joint short section, and the sealing ball is detachably arranged on the sealing ball seat; the gap bridge outer barrel is connected to the blind plug short section and the lower connector short section in a sleeving mode, an annular flow channel is formed between the inner wall of the gap bridge outer barrel and the outer wall of the lower connector short section, and a second water injection hole communicated with the annular flow channel is formed in the lower connector short section; a first liquid flow channel, a second liquid flow channel, a third liquid flow channel and a fourth liquid flow channel which are formed in the upper connector short section, the bypass short section, the sealing ball, the sealing ball seat, the gap bridge short section, the blind plug short section and a main body of the gap bridge outer cylinder are sequentially communicated. The layered water injection device is simple in structure, convenient and fast in layered water injection operation and low in fault risk.

Description

Technical Field

[0001] The present application belongs to the technical field of oilfield production equipment, and in particular, relates to a stratified water injection device. Background Art

[0002] The stratified water injection technology for oil field exploitation is to separate the injection layers, and control the injection volume of the medium and low permeability layers and the high permeability layers while maintaining the same wellhead pump pressure, to prevent the injected water from advancing into a single layer, achieve roughly uniform advancement of each oil layer, and improve the overall recovery rate of the oil field.

[0003] At present, the most commonly used stratified injection technology is the concentric double-tube string; the string is equipped with double-layer oil pipes and double-layer isolation tools, which cooperate to form a seat seal to separate two water injection channels underground, and then inject water into the string through the two water injection layers, and use the outer layer of the oil pipe to inject water into the upper layer and the inner layer of the oil pipe to inject water into the lower layer. In practical applications, the stratification effect of the existing stratified water injection string is not ideal, and it is easily affected by the disturbance of the string and the seat seal structure, so that different water flows are mixed together, impacting the string, damaging the water injection string, and affecting the working efficiency of the water injection string. On the other hand, the main structures in the string all adopt a fixed connection method. When it is necessary to carry out minor repairs and inspections on the oil well, all the water injection strings in the well need to be lifted out, which makes it difficult to unseal and greatly increases the load on the string for minor repairs, resulting in stuck strings and failure to lift the strings, which is easy to cause complex accidents underground and increase operating costs. Summary of the invention

[0004] The present application provides a stratified water injection device, which aims to at least to some extent solve the technical problems of the stratified water injection device having complex functional structure, unsatisfactory stratified water injection effect and working efficiency, and easy jamming failure.

[0005] A stratified water injection device provided in an embodiment of the present application includes: an upper joint nipple, a bypass nipple, a sealing ball, a sealing ball seat, a bridge nipple, a blind plug nipple, a bridge outer cylinder and a lower joint nipple;

[0006] The upper joint nipple, the bypass nipple, the bridge nipple and the blind plug nipple are connected in sequence, and the lumen flow channels opened inside the upper joint nipple, the bypass nipple and the bridge nipple are connected in sequence, and the bypass nipple is provided with a first water injection hole;

[0007] The sealing ball seat is arranged between the bypass short section and the upper joint short section, and the sealing ball is detachably arranged on the sealing ball seat to openably seal the flow passage between the upper joint short section and the bypass short section;

[0008] The bridge outer cylinder is sleeved on the blind plug short joint and the lower joint short joint respectively, and an annular flow passage is formed between the inner wall of the bridge outer cylinder and the outer wall of the lower joint short joint. A second water injection hole communicating with the annular flow passage is opened on the lower joint short joint;

[0009] A first liquid flow channel is opened on the upper joint short joint, a second liquid flow channel is opened on the bypass short joint, a third liquid flow channel is opened on the bridge short joint, and a fourth liquid flow channel is opened on the blind plug short joint. The first end of the first liquid flow channel communicates with the lumen flow passage in the upper joint short joint, and the second end of the first liquid flow channel communicates with the annular flow passage through the second liquid flow channel, the third liquid flow channel and the fourth liquid flow channel which are connected in sequence.

[0010] In some embodiments, a detachable back - connecting insert is arranged in the upper joint short joint to connect the upstream water injection string.

[0011] In some embodiments, the back - connecting insert is screwed in the upper joint short joint.

[0012] In some embodiments, the end of the bypass short joint is sleeved on the end of the upper joint short joint, and the sealing ball seat is arranged inside the bypass short joint and is connected with the end of the upper joint short joint.

[0013] In some embodiments, a shear pin is connected between the sealing ball seat and the bypass short joint.

[0014] In some embodiments, one or more of the first liquid flow channel, the second liquid flow channel, the third liquid flow channel and the fourth liquid flow channel are kidney - shaped slot holes.

[0015] In some embodiments, a first adapted annular flow passage is arranged between the upper joint short joint and the bypass short joint, and the first liquid flow channel communicates with the second liquid flow channel through the first adapted annular flow passage;

[0016] A second adapted annular flow passage is arranged between the bypass short joint and the bridge short joint, and the second liquid flow channel communicates with the third liquid flow channel through the second adapted annular flow passage;

[0017] A third adapted annular flow passage is arranged between the bridge short joint and the blind plug short joint, and the third liquid flow channel communicates with the fourth liquid flow channel through the third adapted annular flow passage.

[0018] In some embodiments, the number of the first liquid flow channel, the second liquid flow channel, the third liquid flow channel and the fourth liquid flow channel is multiple.

[0019] In some embodiments, there are multiple second water injection holes, and the multiple second water injection holes are arranged at equal intervals along the circumferential direction of the lower joint nipple.

[0020] In some embodiments, the sealing ball is a soluble valve ball.

[0021] The embodiments of the present application at least have the following beneficial effects:

[0022] The layered water injection device provided by the embodiments of the present application forms the basis of the entire device through the upper joint nipple, bypass nipple, cross-over nipple, blind plug nipple, cross-over outer cylinder, and lower joint nipple connected in sequence; the lumen flow channels opened inside the upper joint nipple, the bypass nipple, and the cross-over nipple are connected in sequence, and a first water injection hole is opened on the bypass nipple to form a first-layer water injection flow channel; a first liquid flow channel is opened on the upper joint nipple, a second liquid flow channel is opened on the bypass nipple, a third liquid flow channel is opened on the cross-over nipple, a fourth liquid flow channel is opened on the blind plug nipple, an annulus flow channel is formed between the inner wall of the cross-over outer cylinder and the outer wall of the lower joint nipple, and a second water injection hole communicating with the annulus flow channel is opened on the lower joint nipple, and the first end of the first liquid flow channel communicates with the lumen flow channel inside the upper joint nipple, and the second end of the first liquid flow channel communicates with the annulus flow channel through the second liquid flow channel, the third liquid flow channel, and the fourth liquid flow channel connected in sequence to form a second-layer water injection flow channel; thus, two-layer water injection flow channels are formed on an overall structure. On the other hand, the sealing ball seat is arranged between the bypass nipple and the upper joint nipple, and the sealing ball is detachably arranged on the sealing ball seat to seal the flow channel between the upper joint nipple and the bypass nipple in an openable manner, so as to direct the working fluid to the second-layer water injection flow channel for pressurizing and setting the packer in the tubing string connected downstream of the lower joint nipple, thereby sealing the complete second-layer water injection flow channel; then, water can be injected through the upper joint nipple to inject water into two oil layers in the first-layer water injection flow channel and the second-layer water injection flow channel respectively. It should be noted that the layered water injection structure is integrally designed, can be integrally connected to the downhole tubing string, has good compatibility, the layered water injection operation is simple, the function is stable and reliable, and has good layered water injection efficiency. On the other hand, the overall structure is simple and stable, the conversion of the water injection flow channel is implemented within an integrated short section, the anti-interference ability is strong, and the risks of jamming and failure are relatively low. Description of the Drawings

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 Shows a schematic structural diagram of a layered water injection device in an embodiment of the present application;

[0025] Figure 2 Is Figure 1 The A-A cross-sectional view of.

[0026] Reference numerals:

[0027] 100 - upper joint nipple, 110 - first liquid flow channel, 120 - first adapted annular flow channel;

[0028] 200 - bypass nipple, 210 - second liquid flow channel, 220 - shear pin, 230 - second adapted annular flow channel, 240 - first water injection hole;

[0029] 300 - cross-over nipple, 310 - third liquid flow channel, 320 - third adapted annular flow channel;

[0030] 400 - blind plug nipple, 410 - fourth liquid flow channel;

[0031] 500 - cross-over outer cylinder, 510 - annulus flow channel;

[0032] 600 - lower joint nipple, 610 - second water injection hole;

[0033] 700 - sealing ball seat, 710 - sealing ball;

[0034] 800 - tie-back insert head. Detailed implementation manners

[0035] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0036] In addition, the present application may repeat reference numerals and / or reference letters in different examples. This repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or arrangements discussed. In addition, the present application provides examples of various specific processes and materials, but those of ordinary skill in the art may be aware of the application of other processes and / or the use of other materials.

[0037] Next, the present application will be described in conjunction with the accompanying drawings and with reference to specific embodiments:

[0038] The separate layer water injection process forms two water injection flow channels by using a double-layer pipe string in combination with a packer tool and a packer pipeline, and injects water into two oil layers through an upstream water injection device. However, the continuous setting and separating operation is relatively complex, the structure is complex, and it is easily affected by disturbances, resulting in unsatisfactory separate layer water injection effect, and sticking and pipe lifting failures may occur.

[0039] Therefore, the embodiment of the present application provides a separate layer water injection device, aiming to at least solve the technical problems of complex functional structure of the separate layer water injection device, unsatisfactory separate layer water injection effect and working efficiency, and easy sticking and blocking failures to a certain extent.

[0040] See Figure 1 and Figure 2 In some embodiments, the separate layer water injection device may include: an upper joint nipple 100, a bypass nipple 200, a crossover nipple 300, a blind plug nipple 400, a crossover outer cylinder 500, a lower joint nipple 600, a sealing ball seat 700 and a sealing ball 710.

[0041] Among them, the upper joint nipple 100, the bypass nipple 200, the crossover nipple 300, the blind plug nipple 400, the crossover outer cylinder 500 and the lower joint nipple 600 are sequentially connected to form a tubular structure with a certain length as a whole, which can be integrally connected to the downhole pipe string, that is, the upper joint nipple 100 is connected to the upstream water injection pipe, and the lower joint nipple 600 is connected to the downstream pipe string.

[0042] The pipe cavity flow channels opened inside the upper joint nipple 100, the bypass nipple 200 and the crossover nipple 300 are sequentially communicated. The blind plug nipple 400 plugs the bottom end of the crossover nipple 300. A first water injection hole 240 is opened on the bypass nipple 200, thereby forming a first water injection flow channel, that is, the pipe cavity flow channel from the upper port of the upper joint nipple 100 to the first water injection hole 240.

[0043] The crossover outer cylinder 500 is sleeved on the blind plug nipple 400 and the lower joint nipple 600 respectively, so that an annular flow channel 510 is formed between the inner wall of the crossover outer cylinder 500 and the outer wall of the lower joint nipple 600. A second water injection hole 610 communicated with the annular flow channel 510 is opened on the lower joint nipple 600.

[0044] A first fluid flow channel 110 is provided on the upper joint nipple 100, a second fluid flow channel 210 is provided on the bypass nipple 200, a third fluid flow channel 310 is provided on the crossover nipple 300, and a fourth fluid flow channel 410 is provided on the blind plug nipple 400. The first end of the first fluid flow channel 110 is communicated with the lumen flow channel in the upper joint nipple 100, and the second end of the first fluid flow channel 110 is communicated with the annulus flow channel 510 through the second fluid flow channel 210, the third fluid flow channel 310, and the fourth fluid flow channel 410 that are communicated in sequence, so as to form a second water injection flow channel from the port of the first fluid flow channel 110 to the second water injection hole 610.

[0045] Thus, the water injected by the upstream water injection equipment respectively enters the two oil layers through the first water injection flow channel and the second water injection flow channel.

[0046] Correspondingly, in order to form a complete second water injection flow channel, the sealing ball seat 700 is arranged between the bypass nipple 200 and the upper joint nipple 100, and the sealing ball 710 is detachably arranged on the sealing ball seat 700 to seal the flow channel between the upper joint nipple 100 and the bypass nipple 200 in an openable manner, so that the working fluid injected upstream can be introduced into the second water injection flow channel, and the packer assembly downstream of the lower joint nipple 600 can be pressured to set, thereby blocking the downstream pipeline, so that the second water injection flow channel can stably inject the corresponding oil layer.

[0047] Then, the sealing ball 710 can be removed, the sealing ball seat 700 can be opened, and the first water injection flow channel can be conducted, so that the first layer of oil layer can be water-injected.

[0048] In some embodiments, in order to facilitate the connection of the upstream pipe string, a detachable back connection insert head 800 can be arranged in the upper joint nipple 100. When it is necessary to connect the upstream water injection pipe string, it can be installed in the upper joint nipple 100, and then the back connection insert head 800 can be connected to the upstream pipe string.

[0049] In some embodiments, the back connection insert head 800 can be screwed into the upper joint nipple 100 to facilitate the disassembly and assembly operations.

[0050] Generally speaking, in order to improve the sealing performance of the connection part, a sealing element, such as a sealing ring, a sealing sleeve, etc., can be arranged between the back connection insert head 800 and the upper joint nipple 100.

[0051] In some embodiments, for the convenience of installation, the end of the bypass nipple 200 can be sleeved on the end of the upper sub nipple 100, and the sealing ball seat 700 is arranged inside the bypass nipple 200 and is connected to the end of the upper sub nipple 100, and the sealing ball 710 is sealed and placed at the port of the bypass nipple to seal the first water injection flow path.

[0052] In some embodiments, for improving the fault tolerance performance, the sealing ball seat 700 can be movably embedded inside the port of the bypass nipple 200, and a shear pin 220 can be connected between the sealing ball seat 700 and the bypass nipple 200; so that when the sealing ball seat 700 or the sealing ball 710 is jammed or inconvenient to remove, the shear pin 220 is cut off by pressurization to conduct the first water injection flow path.

[0053] In some embodiments, one or several of the first liquid flow channel 110, the second liquid flow channel 210, the third liquid flow channel 310, and the fourth liquid flow channel 410 are kidney-shaped slot holes to obtain a flow channel structure with a certain width and improve the fluidity.

[0054] In some embodiments, the bypass nipple 200 can be screwed and sleeved on the upper sub nipple 100, and a seal can be arranged at the connection part.

[0055] In some embodiments, for improving the connection fault tolerance between the first liquid flow channel 110 and the second liquid flow channel 210, a certain annular fitting gap can be left between the upper sub nipple 100 and the bypass nipple 200 as the first fitting annular flow channel 120, and the first liquid flow channel 110 and the second liquid flow channel 210 can be connected through the first fitting annular flow channel 120. Therefore, even if the first liquid flow channel 110 and the second liquid flow channel 210 are not accurately aligned, the first fitting annular flow channel 120 can still be used for conduction.

[0056] Similarly, a second fitting annular flow channel 230 is arranged between the bypass nipple 200 and the cross-over nipple 300, and the second liquid flow channel 210 and the third liquid flow channel 310 are connected through the second fitting annular flow channel 230. Therefore, even if the second liquid flow channel 210 and the third liquid flow channel 310 are not accurately aligned, the second fitting annular flow channel 230 can still be used for conduction.

[0057] A third adapted annular flow passage 320 is provided between the cross-over nipple 300 and the blind plug nipple 400. The third liquid flow passage 310 and the fourth liquid flow passage 410 are communicated through the third adapted annular flow passage 320. Therefore, even if the third liquid flow passage 310 and the fourth liquid flow passage 410 are not accurately aligned, the third adapted annular flow passage 320 can still be used for conduction.

[0058] In some embodiments, in order to improve the water injection efficiency, the number of the first liquid flow passage 110, the second liquid flow passage 210, the third liquid flow passage 310 and the fourth liquid flow passage 410 can all be multiple, so as to expand the water injection area.

[0059] Generally, multiple first liquid flow passages 110, multiple second liquid flow passages 210, multiple third liquid flow passages 310 and multiple fourth liquid flow passages 410 can be arranged at equal intervals respectively.

[0060] In some embodiments, the number of the second water injection holes 610 can also be multiple, and the multiple second water injection holes 610 are arranged at equal intervals along the circumferential direction of the lower joint nipple 600, so as to improve the water injection efficiency.

[0061] In some embodiments, in order to improve the packing and unpacking efficiency of the sealing ball seat 700, the sealing ball 710 can be set as a soluble valve ball, which will gradually dissolve naturally after the pressure test and setting of the second water injection flow passage, simplifying the operation of unpacking the first water injection flow passage and improving the efficiency.

[0062] The embodiments of the present application at least have the following beneficial effects:

[0063] The layered water injection device provided by the embodiment of the present application forms the basis of the entire device through a series of components connected in sequence, including an upper joint nipple, a bypass nipple, a crossover nipple, a blind plug nipple, a crossover outer cylinder, and a lower joint nipple. The lumen channels opened inside the upper joint nipple, the bypass nipple, and the crossover nipple are sequentially connected. A first water injection hole is opened on the bypass nipple to form a first layer of water injection flow path. A first liquid flow channel is opened on the upper joint nipple, a second liquid flow channel is opened on the bypass nipple, a third liquid flow channel is opened on the crossover nipple, a fourth liquid flow channel is opened on the blind plug nipple, and an annulus flow path is formed between the inner wall of the crossover outer cylinder and the outer wall of the lower joint nipple. A second water injection hole communicating with the annulus flow path is opened on the lower joint nipple. The first end of the first liquid flow channel communicates with the lumen channel inside the upper joint nipple, and the second end of the first liquid flow channel communicates with the annulus flow path through the sequentially connected second liquid flow channel, third liquid flow channel, and fourth liquid flow channel, forming a second layer of water injection flow path. Thus, two layers of water injection flow paths are formed on an integral structure. On the other hand, the sealing ball seat is arranged between the bypass nipple and the upper joint nipple, and the sealing ball is detachably arranged on the sealing ball seat to seal the flow path between the upper joint nipple and the bypass nipple in an openable manner, so as to direct the working fluid to the second layer of water injection flow path for pressure testing and setting the packer in the tubing string downstream of the lower joint nipple, thereby sealing the complete second layer of water injection flow path. Then, water can be injected through the upper joint nipple to inject water into two oil layers in the first layer of water injection flow path and the second layer of water injection flow path respectively. It should be noted that the layered water injection structure is integrally designed, can be integrally connected to the downhole tubing string, has good compatibility, simple and convenient layered water injection operation, stable and reliable functions, and good layered water injection efficiency. On the other hand, the overall structure is simple and stable, the conversion of the water injection flow path is implemented within an integrated short section, with strong anti-interference ability and low risks of jamming and failure.

[0064] In this application, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may include direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features between them. Moreover, the first feature being "above", "over", and "on top of" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature has a higher horizontal height than the second feature. The first feature being "under", "below", and "beneath" the second feature includes the first feature being directly below and obliquely below the second feature, or simply indicating that the first feature has a lower horizontal height than the second feature.

[0065] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application 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 should not be construed as a limitation to the present application.

[0066] It should be noted that all directional indications in the embodiments of the present application are only used to explain the relative positional relationship and movement conditions between components in a specific posture. If this specific posture changes, the directional indication will also change accordingly.

[0067] In the present application, unless otherwise clearly defined and limited, terms such as "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0068] In addition, in the present application, the descriptions such as "first" and "second" are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present application, "a plurality" means two or more, unless otherwise clearly and specifically defined.

[0069] In the description of this specification, the descriptions with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean 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 present application. In this specification, the schematic descriptions 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, those skilled in the art can combine and combine the different embodiments or examples described in this specification.

[0070] In addition, the technical solutions between various embodiments can be combined with each other, provided that they can be implemented by those of ordinary skill in the art. When the combination of technical solutions leads to contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0071] Although the embodiments of the present application have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present application. The scope of the present application is defined by the claims and their equivalents.

Claims

1. A layered water injection device, characterized in that, Comprising: Upper joint nipple, bypass nipple, sealing ball, sealing ball seat, crossover nipple, blind plug nipple, crossover outer barrel and lower joint nipple; The upper joint nipple, the bypass nipple, the crossover nipple and the blind plug nipple are connected in sequence, and the lumen flow channels formed inside the upper joint nipple, the bypass nipple and the crossover nipple are communicated in sequence. A first water injection hole is formed on the bypass nipple; The sealing ball seat is arranged between the bypass nipple and the upper joint nipple, and the sealing ball is detachably arranged on the sealing ball seat to seal the flow channel between the upper joint nipple and the bypass nipple in an openable manner; The crossover outer barrel is sleeved on the blind plug nipple and the lower joint nipple respectively, and an annulus flow channel is formed between the inner wall of the crossover outer barrel and the outer wall of the lower joint nipple. A second water injection hole communicated with the annulus flow channel is formed on the lower joint nipple; A first liquid flow channel is formed on the upper joint nipple, a second liquid flow channel is formed on the bypass nipple, a third liquid flow channel is formed on the crossover nipple, and a fourth liquid flow channel is formed on the blind plug nipple. The first end of the first liquid flow channel is communicated with the lumen flow channel inside the upper joint nipple, and the second end of the first liquid flow channel is communicated with the annulus flow channel through the second liquid flow channel, the third liquid flow channel and the fourth liquid flow channel which are communicated in sequence; 2. The layered water injection device according to claim 1, wherein, A detachable back connection insert is arranged inside the upper joint nipple to connect the upstream water injection string; 3. The layered water injection device according to claim 2, characterized in that The back connection insert is screwed inside the upper joint nipple; 4. The layered water injection device according to claim 1, characterized in that, The end of the bypass nipple is sleeved on the end of the upper joint nipple, and the sealing ball seat is arranged inside the bypass nipple and is connected with the end of the upper joint nipple; 5. The layered water injection device according to claim 4, characterized in that A shear pin is connected between the sealing ball seat and the bypass nipple; 6. The layered water injection device according to claim 1, characterized in that, One or several of the first liquid flow channel, the second liquid flow channel, the third liquid flow channel and the fourth liquid flow channel are kidney-shaped slot holes; 7. The layered water injection device according to claim 6, characterized in that, A first adapted annular flow channel is arranged between the upper joint nipple and the bypass nipple, and the first liquid flow channel is communicated with the second liquid flow channel through the first adapted annular flow channel; A second adapted annular flow channel is arranged between the bypass nipple and the crossover nipple, and the second liquid flow channel is communicated with the third liquid flow channel through the second adapted annular flow channel; A third adapted annular flow channel is arranged between the crossover nipple and the blind plug nipple, and the third liquid flow channel is communicated with the fourth liquid flow channel through the third adapted annular flow channel; 8. The layered water injection device according to claim 7, wherein, The number of the first liquid flow channel, the second liquid flow channel, the third liquid flow channel and the fourth liquid flow channel is multiple; 9. The layered water injection device according to claim 1, wherein, The second water injection holes are multiple, and the multiple second water injection holes are arranged at equal intervals along the circumference of the lower joint nipple; 10. The layered water injection device according to claim 1, characterized in that, The sealing ball is a soluble valve ball.

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