A downhole separate layer water injection instrument

Abstract

The utility model provides a kind of underground layered water injection instrument, including motor, motor shaft coupling, middle lead screw, middle coupling, tail end lead screw, hollow cylinder base, water nozzle valve element assembly, lower joint;At least one strip length or local or point of rib is axially arranged on the outer wall surface of the left end portion of base body, or at least one length groove is axially arranged on the outer wall surface of the left end portion of base body;Anti-rotation screw is fixed with the base of hollow cylinder, and its head is stretched into the groove.The at least one strip length or local or point of rib is axially arranged on the outer wall surface of the left end portion of water nozzle valve element assembly base body, or at least one length groove is arranged, so that water nozzle valve element assembly reciprocates linearly in the base of hollow cylinder, changes from surface contact to narrow strip contact, line contact, even point contact, greatly reduces friction force during reciprocating linear motion between them, reduces the risk of sand plug, improves water nozzle reliability.

Description

Technical Field

[0001] This utility model belongs to the field of intelligent layered water injection technology in oilfields, and specifically relates to a downhole layered water injection device. Background Technology

[0002] Currently, intelligent stratified water injection in oilfields is an important technology for increasing formation pressure, reducing water injection cross-contamination, and improving oilfield recovery. The key equipment used in this technology is the downhole stratified water injection system, which can intelligently monitor the injection pressure and flow parameters of corresponding layers downhole, thus saving significant manpower and material costs. In the downhole stratified water injection system, the core regulating component is the nozzle valve core assembly. This assembly relies on a motor drive and control circuit to perform switching and opening adjustments, thereby achieving stratified water injection flow rate regulation.

[0003] The existing nozzle valve core assembly of downhole stratified water injection devices has the following problems: Existing downhole stratified water injection instruments mostly use balanced pressure water nozzle valve core assemblies, including a cylindrical base with a left end and a right end. This water nozzle valve core assembly needs to convert the rotary circular motion of the motor into reciprocating linear motion along the axis. The water nozzle valve core assembly includes a cylindrical base with a left end and a right end. The left end of the base includes a left end body and its internal trapezoidal thread. The right end of the base includes a right end body, a ceramic cap, and a screw. The ceramic cap is fitted over the right end body and fixed with the screw. The left end body is integrated with the right end body of the base. Specifically, the motor drives the lead screw, and the lead screw and the left end body of the base are connected by an internal trapezoidal thread. The most critical part is that the elliptical outer wall of the left end body of the base and the circular inner wall of the hollow cylindrical base are connected by a flat position to restrict circumferential rotation, thereby realizing the rotation of the lead screw to drive the reciprocating linear motion of the base. This flat position restriction structure is a surface-to-surface fit, which has high friction. Especially when the water contains sand, the friction between the surfaces will increase significantly, eventually causing the water nozzle valve core assembly to jam.

[0004] In addition, the ceramic cap and ceramic bushing of the existing balanced pressure water nozzle valve core assembly are mostly fitted with conventional H8 / f7 sealing surfaces. This excessively long sealing surface will greatly increase the axial reciprocating friction under high pressure and sandy water conditions, which will lead to the water nozzle valve core assembly jamming. Summary of the Invention

[0005] To address the aforementioned problems with the nozzle valve core assembly in existing downhole stratified water injection devices, the purpose of this invention is to provide a stratified water injection device with a nozzle valve core assembly that exhibits low friction and is less prone to jamming during reciprocating motion. The device includes a motor, motor coupling, intermediate lead screw, intermediate coupling, tail lead screw, hollow cylindrical base, nozzle valve core assembly, lower connector of the hollow cylinder, ceramic bushing, and sealing gasket assembly. The hollow cylindrical base and lower connector are connected together by threads and are sequentially fixedly connected from left to right among them: motor, motor coupling, intermediate lead screw, intermediate coupling, tail lead screw, and nozzle valve core assembly. The inner wall of the hollow cylindrical base has a circular cross-section, and the nozzle valve core assembly comprises a cylindrical... The base has a left end and a right end. The left end includes a left end body and its internal trapezoidal thread. The right end includes a right end body, a ceramic cap, and a countersunk screw. The ceramic cap is fitted over the right end body and fixed by the countersunk screw. The left end body and the right end body are integrated. The left end body is connected to the tail screw through its internal trapezoidal thread. The ceramic cap is fixed inside the lower connector nozzle through a ceramic bushing and sealing gasket assemblies at both ends. The ceramic cap and the sealing gasket assemblies are tightly fitted. The cross-section of the outer wall of the left end body is circular. At least one elongated, partial, or dotted ridge is axially provided on the outer wall of the left end body.

[0006] Preferably, two, three, or four elongated, partial, or dotted ridges are provided axially on the outer wall surface of the left end of the substrate.

[0007] Preferably, the two, three, or four strip-shaped, elongated, partial, or dot-shaped edges are evenly distributed on the outer wall surface of the left end of the substrate.

[0008] This utility model also provides another downhole stratified water injection device, including a motor, a motor coupling, an intermediate lead screw, an intermediate coupling, a tail lead screw, a hollow cylindrical base, a water nozzle valve core assembly, a lower connector of the hollow cylindrical body, a ceramic bushing, and a sealing gasket assembly; the hollow cylindrical base and the lower connector are connected together by threads and are fixedly connected from left to right among them: the motor, the motor coupling, the intermediate lead screw, the intermediate coupling, the tail lead screw, and the water nozzle valve core assembly; the cross-section of the inner wall of the hollow cylindrical base is circular, and the water nozzle valve core assembly includes a left end and a right end of a cylindrical base. The left end of the base includes a left end body and its internal trapezoidal thread, and the right end of the base includes a right end body, a ceramic cap, and a countersunk screw. The base is fitted onto the right end of the main body and fixed with countersunk screws. The left end of the main body is integrated with the right end of the main body. The left end of the main body is connected to the tail screw through its internal trapezoidal thread. The ceramic cap is fixed inside the water nozzle of the lower connector through a ceramic bushing and sealing gasket assemblies at both ends. The ceramic cap and the sealing gasket assemblies are tightly fitted. It also includes an anti-rotation screw with an external thread on the screw cap. The cross-section of the outer wall of the left end of the main body is circular. At least one continuous groove is provided axially on the outer wall of the left end of the main body. The anti-rotation screw is screwed into the anti-rotation screw threaded hole on the outer wall of the hollow cylinder base in the connection section between the hollow cylinder base and the lower connector through its external thread on the screw cap, and its head extends into the groove.

[0009] Preferably, two, three, or four through-length grooves are provided axially on the outer wall surface of the left end of the substrate.

[0010] Preferably, the two, three, or four elongated grooves are evenly distributed on the outer wall surface of the left end of the substrate.

[0011] Preferably, the ceramic cap is a hollow columnar body with one end open and the other end closed; the countersunk screw is a countersunk sidewall screw; the ceramic cap is connected and fixed to the right end of the base body on its sidewall by the countersunk sidewall screw.

[0012] Preferably, the installation gap between the ceramic cap and the ceramic bushing satisfies the requirement of a large clearance fit installation.

[0013] Preferably, the sealing gasket assembly mainly consists of a hollow annular metal sealing gasket and a rubber sealing ring around its periphery.

[0014] This invention provides a downhole stratified water injection device. By axially providing at least one elongated, partial, or point-like ridge, or at least one elongated groove, on the outer wall of the left end of the nozzle valve core assembly base, the nozzle valve core assembly reciprocates linearly within the hollow cylindrical base. This transforms surface contact into narrow strip contact, line contact, or even point contact, significantly reducing friction during the reciprocating linear motion, lowering the risk of jamming, and improving nozzle reliability. Furthermore, by employing a large clearance fit between the ceramic cap and ceramic bushing in the nozzle valve core assembly, the friction between them during reciprocating motion is greatly reduced, while also lowering the opening torque of the nozzle valve core assembly and preventing jamming. Attached Figure Description

[0015] Figure 1 This utility model provides a schematic diagram of a friction-reducing water nozzle structure for a stratified water injection device; Figure 2 for Figure 1 Enlarged view of part of E in the middle; Figure 3 for Figure 1 An exploded view of the faucet valve core assembly structure shown in the figure; Figure 4 for Figure 1 The cross-sectional view (left) and three-dimensional view (right) of the anti-rotation screw are shown in the figure. Figure 5 for Figure 1 The diagram shows the side profile (left) and FF cross-section (right) of the ceramic bushing.

[0016] The figures are labeled as follows: 1. Motor; 11. Motor coupling; 12. Intermediate lead screw; 13. Intermediate coupling; 14. Tail-end lead screw; 2. Hollow cylindrical base; 3. Water nozzle valve core assembly; 31. Left end of the base; 311. Left end of the base body; 312. Groove; 313. First anti-friction groove guide wall; 314. Second anti-friction groove guide wall; 315. Guide opening; 32. Right end of the base; 32 1. Right end of the base body; 322. Ceramic cap; 323. Countersunk sidewall screw; 4. Anti-rotation screw; 41. Internal hexagonal socket; 42. External thread; 43. Anti-friction surface; 44. Anti-friction step; 5. Lower connector of hollow cylinder; 51. Layer inlet; 52. Layer outlet; 6. Ceramic bushing; 61. Bushing anti-friction surface; 7. Sealing gasket assembly; 71. Hollow annular metal sealing gasket; 72. Rubber sealing ring. Detailed Implementation

[0017] Furthermore, the technical solution claimed by this utility model will be described in detail with reference to specific embodiments and accompanying drawings.

[0018] This utility model provides a downhole stratified water injection device, such as... Figure 1 and Figure 2 As shown, the assembly includes a motor 1, a motor coupling 11, an intermediate lead screw 12, an intermediate coupling 13, a tail lead screw 14, a hollow cylindrical base 2, a water tap valve core assembly 3, a lower connector 5 of the hollow cylindrical body, a ceramic bushing 6, and a sealing gasket assembly 7. The hollow cylindrical base 2 and the lower connector 5 are connected together by threads and are sequentially fixedly connected from left to right among them: motor 1, motor coupling 11, intermediate lead screw 12, intermediate coupling 13, tail lead screw 14, and water tap valve core assembly 3. The inner wall of the hollow cylindrical base 2 has a circular cross-section. The water tap valve core assembly 3 includes a cylindrical base with a left end 31 and a base with a right end 32. The left end 31 includes a left end body 311 and its internal trapezoidal thread. The right end 32 includes a right end body 321, a ceramic cap 322, and a countersunk sidewall screw 323. The cap 322 is fitted over the right end body 321 of the base and fixed by countersunk sidewall screws 323. The left end body 311 of the base is integrated with the right end body 321 of the base. The left end body 311 of the base is connected to the tail screw 14 through its internal trapezoidal thread. The ceramic cap 322 is tightly fixed in the water inlet of the lower connector 5 through the ceramic bushing 6 and the sealing gasket assemblies 7 at both ends. The downhole stratified water injection instrument also includes an anti-rotation screw 4 with an external thread on the screw cap. At least one through-length groove 312 is provided axially on the outer wall of the left end body 311 of the base. The cross-section of the outer wall of the left end body 311 of the base is circular. The anti-rotation screw 4 is screwed into the anti-rotation screw thread hole on the outer wall of the hollow cylindrical base 2 in the connection section between the hollow cylindrical base 2 and the lower connector 5 through its external thread, and its head extends into the groove 312.

[0019] like Figure 1 As shown, 1) Water flow direction of the downhole stratified water injection instrument: The water flow of the stratum enters from the stratum inlet 51, flows through the channel indicated by the arrow from the lower connector 5, and finally flows out through the stratum outlet 52 and is injected into the formation. 2) Torque transmission of the downhole stratified water injection instrument: The motor 1 and the intermediate lead screw 12 are connected through the motor coupling 11, which transmits the rotational motion of the motor 1 to the intermediate lead screw 12; further, the intermediate lead screw 12 is connected to the tail lead screw 14 through the intermediate coupling 13, which transmits the rotational motion to the tail lead screw 14; finally, the tail lead screw 14 is connected to the water nozzle valve core assembly 3 through the trapezoidal thread, which converts the rotational motion of the water nozzle valve core assembly 3 into reciprocating linear motion.

[0020] The rotary motion of the faucet valve core assembly 3 is converted into reciprocating linear motion: such as Figure 2As shown, the tail screw 14 is connected to the left end 31 of the base body in the water tap valve core assembly 3 via a trapezoidal thread; the anti-rotation screw 4 is fixed in the anti-rotation screw hole at the corresponding position of the hollow cylindrical base 2 through its M4 external thread 42, so that the anti-rotation screw 4 is fixed in place; the friction-reducing surface 43 of the anti-rotation screw 4 contacts and slides with the first friction-reducing groove guide wall 313 and the second friction-reducing groove guide wall 314 in at least one groove 312 on the outer wall surface of the left end body 311 of the base body; the rotation of the tail screw 14 drives the water tap valve core assembly 3 to reciprocate linearly along the axial direction. Since the anti-rotation screw 4 contacts the strip surface (i.e., line contact) formed by the first friction-reducing groove guide wall 313 and the second friction-reducing groove guide wall 314, the rotational motion of the water tap valve core assembly 3 is transformed into a reciprocating linear motion. The left end body 311 of the base body and the hollow cylindrical base 2 are in line contact, rather than the surface contact in the prior art. This greatly reduces the friction, reduces the risk of sand jamming, and improves the reliability of the water tap.

[0021] Furthermore, the hollow cylindrical base 2 and the lower connector 5 are threaded together to tighten the anti-rotation screw 4, which can prevent the anti-rotation screw 4 from loosening and coming off due to long-term vibration; at the same time, the hollow cylindrical base 2 is designed with a stepped surface to support the anti-rotation screw 4, which reduces friction. Figure 4 As shown, this ensures that the anti-rotation screw 4 is reliably secured.

[0022] Furthermore, such as Figure 3 As shown, when assembling the water tap valve core assembly 3, a flared guide port 315 is provided at the left end of the groove 312 on the outer wall surface of the body 311 at the left end of the base, which can facilitate the anti-rotation screw 4 to enter the groove 312.

[0023] Furthermore, such as Figure 4 As shown, the upper end face of the anti-rotation screw 4 is designed with an internal hexagonal opening 41 to facilitate tightening of the anti-rotation screw 4.

[0024] Furthermore, such as Figure 2 As shown, the outer diameter design dimension of ceramic cap 322 is ΦN; as Figure 5 As shown, the inner surface of the ceramic bushing 6 is the bushing friction-reducing surface 61, and its inner diameter is ΦM. The difference between M and N must be designed to meet the requirements of a large clearance fit (such as a fit clearance of 1 mm). Compared with the existing technology of sealing surface H8 / f7 fit, such a fit clearance greatly reduces the reciprocating friction of the ceramic cap 322, further reducing the opening torque of the water tap valve core assembly and preventing it from jamming. At the same time, a sealing gasket assembly 7 is used at each end of the ceramic cap 322 and the ceramic bushing 6 to ensure that the friction is reduced without affecting the sealing effect of the water tap valve core assembly. The sealing gasket assembly 7 includes a hollow annular metal sealing gasket 71 and a rubber sealing ring 72 around it.

[0025] Furthermore, in order to prevent water flow from wearing down the right end face of the right end body of the base of the water valve core assembly 3, the ceramic cap is a hollow columnar body with one end open and the other end closed; the countersunk sidewall screw is a countersunk sidewall screw; the ceramic cap is connected and fixed to the right end body of the base by the countersunk sidewall screw on its side wall.

[0026] The above description illustrates a specific downhole stratified water injection device structure. In the above embodiment, at least one elongated groove 312 is provided axially on the outer wall surface of the body 311 at the left end of the substrate. Two elongated grooves 312 are provided, one above the other. Figure 2 As shown, of course, one, three, or four continuous grooves 312 can be provided. To ensure uniform axial force between the faucet valve core assembly 3 and the hollow cylindrical base 2, three or four continuous grooves 312 can be evenly distributed on the outer wall of the left end of the base body. To reduce the friction between the anti-rotation screw and the groove, the cross-section of the groove is designed as trapezoidal or triangular.

[0027] Of course, in the above embodiments, the at least one elongated groove 312 axially provided on the outer wall surface of the body 311 at the left end of the base, and the anti-rotation screw 4 in the base for fixing the hollow cylinder, can be omitted. Instead, at least one elongated, partial, or dotted ridge, such as one, two, three, or four elongated, partial, or dotted ridges, can be axially provided on the outer wall surface of the body 311 at the left end of the base. Similarly, in order to ensure uniform axial force between the water tap valve core assembly 3 and the base 2 of the hollow cylinder, two, three, or four elongated, partial, or dotted ridges can be evenly distributed on the outer wall surface of the body at the left end of the base. To reduce the friction between the anti-rotation screw and the ridge, the cross-section of the ridge is designed as trapezoidal, rectangular, or triangular.

[0028] This utility model is not limited to the above embodiments. Any modifications made by developers in the field through non-creative labor based on the anti-friction water nozzle solution for the stratified water injection device disclosed in this utility model are all within the protection scope of this utility model.

Claims

1. A downhole stratified water injection device, comprising a motor, a motor coupling, an intermediate lead screw, an intermediate coupling, a tail lead screw, a hollow cylindrical base, a water nozzle valve core assembly, a lower connector of the hollow cylindrical body, a ceramic bushing, and a sealing gasket assembly; the hollow cylindrical base and the lower connector are connected together by threads and are sequentially fixedly connected from left to right among them: the motor, the motor coupling, the intermediate lead screw, the intermediate coupling, the tail lead screw, and the water nozzle valve core assembly; the cross-section of the inner wall of the hollow cylindrical base is circular, and the water nozzle valve core assembly includes a left end of the cylindrical base and... The right end of the base includes a left end body and its internal trapezoidal thread, and the right end of the base includes a right end body, a ceramic cap, and a countersunk screw. The ceramic cap is fitted over the right end body and fixed by the countersunk screw. The left end body and the right end body are integrated. The left end body is connected to the tail screw via its internal trapezoidal thread. The ceramic cap is fixed inside the lower connector nozzle via a ceramic bushing and sealing gasket assemblies at both ends, wherein the ceramic cap and the sealing gasket assemblies are tightly fitted. The cross-section of the outer wall of the left end of the substrate is circular, and at least one elongated, partial, or dotted ridge is provided axially on the outer wall of the left end of the substrate.

2. The downhole stratified water injection device according to claim 1, characterized in that, Two, three, or four axially arranged, continuous, partial, or dotted ridges are provided on the outer wall surface of the left end of the substrate.

3. The downhole stratified water injection device according to claim 2, characterized in that, The two, three, or four strip-shaped, elongated, partial, or dot-shaped edges are evenly distributed on the outer wall surface of the left end of the substrate.

4. A downhole stratified water injection device, comprising a motor, a motor coupling, an intermediate lead screw, an intermediate coupling, a tail lead screw, a hollow cylindrical base, a water nozzle valve core assembly, a lower connector of the hollow cylinder, a ceramic bushing, and a sealing gasket assembly; the hollow cylindrical base and the lower connector are connected together by threads and are sequentially fixedly connected from left to right among them: the motor, the motor coupling, the intermediate lead screw, the intermediate coupling, the tail lead screw, and the water nozzle valve core assembly; the cross-section of the inner wall of the hollow cylindrical base is circular, and the water nozzle valve core assembly includes a left end of a cylindrical base and... The right end of the base includes a left end body and its internal trapezoidal thread, and the right end of the base includes a right end body, a ceramic cap, and a countersunk screw. The ceramic cap is fitted over the right end body and fixed by the countersunk screw. The left end body and the right end body are integrated. The left end body is connected to the tail screw via its internal trapezoidal thread. The ceramic cap is fixed inside the lower connector nozzle via a ceramic bushing and sealing gasket assemblies at both ends, wherein the ceramic cap and the sealing gasket assemblies are tightly fitted. It also includes an anti-rotation screw with an external thread on the screw cap; the cross-section of the outer wall of the left end of the base is circular, and at least one through-length groove is provided axially on the outer wall of the left end of the base; the anti-rotation screw is screwed into the anti-rotation screw thread hole on the outer wall of the hollow cylinder base in the connection section between the base of the hollow cylinder and the lower joint through its external thread on the screw cap, and its head extends into the groove.

5. The downhole stratified water injection device according to claim 4, characterized in that, Two, three, or four through-length grooves are provided axially on the outer wall surface of the body at the left end of the substrate.

6. The downhole stratified water injection device according to claim 5, characterized in that, The two, three, or four elongated grooves are evenly distributed on the outer wall surface of the left end of the substrate.

7. The downhole stratified water injection device according to claim 1, 2, 3, 4, 5, or 6, characterized in that, The ceramic cap is a hollow columnar body with one end open and the other end closed; the countersunk screw is a countersunk sidewall screw; the ceramic cap is connected and fixed to the right end of the base body on its sidewall by the countersunk sidewall screw.

8. The downhole stratified water injection device according to claim 7, characterized in that, The installation gap between the ceramic cap and the ceramic bushing meets the requirements for large-gap fit installation.

9. The downhole stratified water injection device according to claim 1, 2, 3, 4, 5, or 6, characterized in that, The installation gap between the ceramic cap and the ceramic bushing meets the requirements for large-gap fit installation.

10. The downhole stratified water injection device according to claim 8, characterized in that, The sealing gasket assembly mainly consists of a hollow annular metal sealing gasket and a rubber sealing ring around its periphery.

11. The downhole stratified water injection device according to claim 9, characterized in that, The sealing gasket assembly mainly consists of a hollow annular metal sealing gasket and a rubber sealing ring around its periphery.

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