Overflow well anti-overflowing and ash injection valve

Abstract

The utility model discloses a kind of overflow well anti-overflowing cement injection valves, comprising: upper joint, main body and lower joint, upper joint, main body and lower joint are sequentially screwed, and the main body inner cavity is equipped with conical lower one-way valve structure, and conical lower one-way valve structure includes valve core, big compression spring and pressure cap, valve core is slidably installed in the main body inner cavity, pressure cap is screwed in the main body bottom end, big compression spring is installed between valve core and pressure cap, and pressure cap is axially provided with eyelet, and the valve core inner cavity is equipped with constant-pressure upper one-way valve structure, and constant-pressure upper one-way valve structure allows liquid to flow from lower to upper one-way from the valve core inner cavity. The utility model injects cement slurry and displacement fresh water by lower one-way valve structure, and the opening pressure of constant-pressure upper one-way valve structure set before well is greater than the shut-in static pressure of overflow layer in well, in closed state, when hoisting equipment fails, from casing annulus pump into flushing fluid, and pump pressure is greater than the opening pressure of constant-pressure upper one-way valve structure, and the cement slurry in well can be backwashed to ground.

Description

Technical Field

[0001] This utility model relates to the field of oil extraction technology, and in particular to an overflow well anti-overflow ash injection valve. Background Technology

[0002] Most oilfields are multi-layered systems with varying water cuts and pressures across layers. During development, especially in the later stages of water injection, inter-layer conflicts become increasingly prominent. It is often necessary to inject cement plugs to seal lower, temporarily unused or abandoned high-water-cut layers. However, when overflow occurs in the upper formation, cement plugs cannot be directly injected because the injected cement slurry is initially fluid, and overflow in the well would flush the slurry out of the wellbore. Currently, the method for injecting cement plugs after upper overflow is to kill the well first. This method is expensive to prepare the kill fluid, requires the use of kill fluid as a displacement fluid during cement plug injection, and the kill fluid affects the performance of the cement slurry. Furthermore, isolation between the two layers is necessary, resulting in high construction risks. Additionally, the kill fluid can easily contaminate the formation. Utility Model Content

[0003] The purpose of this utility model is to provide an overflow well anti-overflow slurry injection valve. Cement slurry and replacement water are injected through a lower single-flow valve structure formed by the main body and valve core. After pumping stops, a large pressure spring pushes the valve core upwards, closing the lower single-flow valve structure. The opening pressure of the constant-pressure upper single-flow valve structure set before running into the well is greater than the shut-in static pressure of the overflow layer in the well. The constant-pressure upper single-flow valve structure is in a closed state, and the pressure inside the well cannot flush the injected cement slurry to the surface along the tubing. In the event of a hoisting equipment failure, well-washing fluid is pumped into the annulus. The pump pressure is greater than the opening pressure of the constant-pressure upper single-flow valve structure, which can backwash the cement slurry in the well to the surface. By integrating the constant-pressure upper single-flow valve structure into the valve core, the valve body size requirement is smaller, which can well adapt to wells with casing deformation.

[0004] To achieve the purpose of this utility model, this utility model provides an overflow well anti-overflow ash injection valve, including: an upper connector, a main body, and a lower connector, which are sequentially threaded together. The main body is designed as a through-hole structure, and the inner cavity of the main body is provided with a conical lower one-way valve structure. The conical lower one-way valve structure includes a valve core, a large compression spring, and a pressure cap. The valve core is slidably installed in the inner cavity of the main body, and the pressure cap is threaded to the bottom end of the main body. The large compression spring is installed between the valve core and the pressure cap. The upper part of the inner cavity of the main body is provided with an inverted conical circular hole, and the top end of the valve core is provided with an outer conical surface that mates with the inverted conical circular hole. The pressure cap has an axially opened eyelet. The valve core is designed as a through-hole structure, and the inner cavity of the valve core is provided with a constant pressure upper one-way valve structure, which allows liquid to flow unidirectionally from bottom to top from the inner cavity of the valve core.

[0005] As a preferred embodiment of this utility model, sealing rings are provided at the connection points between the main body and the upper and lower connectors.

[0006] As a preferred embodiment of this utility model, the valve core is provided with a stop portion near the bottom outer wall, and the large compression spring is installed between the stop portion and the pressure cap.

[0007] As a preferred technical solution of this utility model, the large compression spring presses against the valve core to maintain the normally closed state of the conical lower single-flow valve structure.

[0008] As a preferred technical solution of this utility model, the constant pressure single-flow valve structure includes a valve ball, a small compression spring, a bolt rod, and a pressure plate. The top of the valve core is provided with a conical valve seat, which cooperates with the valve ball. The small compression spring is installed in the inner cavity of the valve core. The pressure plate is slidably installed on the bottom end of the small compression spring. The two ends of the bolt rod are respectively fixedly connected to the valve ball and the pressure plate. The pressure plate has holes opened axially.

[0009] As a preferred embodiment of this utility model, the inner cavity of the valve core is a circular hole, and the inner diameter of the circular hole is larger than the minimum through hole of the conical valve seat.

[0010] As a preferred embodiment of this utility model, an adjusting pad is installed near the end of the conical valve seat in the circular hole, and a small compression spring is installed between the adjusting pad and the pressure plate.

[0011] As a preferred technical solution of this utility model, the preload of the small compression spring is adjusted by increasing or decreasing the thickness or number of the adjusting pads, thereby controlling the opening pressure of the valve ball.

[0012] Compared with the prior art, this utility model provides an overflow well anti-overflow ash injection valve, which has the following beneficial effects: This invention utilizes a lower single-flow valve structure formed by the main body and valve core to inject cement slurry and replace clean water. After pumping stops, a large pressure spring pushes the valve core upward, closing the lower single-flow valve structure. The opening pressure of the constant-pressure upper single-flow valve structure set before running into the well is greater than the shut-in static pressure of the overflow layer in the well. Under the action of a small pressure spring, the bolt rod pulls down the valve ball, and the constant-pressure upper single-flow valve structure is in a closed state. The pressure in the well cannot flush the injected cement slurry to the surface along the tubing. In the event of a hoisting equipment failure, a well-washing fluid is pumped in from the annulus of the casing. The pump pressure is greater than the opening pressure of the constant-pressure upper single-flow valve structure, which can backwash the cement slurry in the well to the surface. This device integrates the constant-pressure upper single-flow valve structure into the valve core, requiring a smaller valve body structure size, and can well adapt to casing deformation wells. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the constant pressure single-flow valve structure of this utility model.

[0014] 1 is the upper connector, 2 is the main body, 3 is the lower connector, 4 is the valve core, 5 is the large compression spring, 6 is the pressure cap, 7 is the constant pressure single-flow valve structure, 8 is the sealing ring, 9 is the valve ball, 10 is the small compression spring, 11 is the bolt rod, 12 is the pressure plate, and 13 is the adjusting pad. Detailed Implementation

[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0016] Please see Figures 1-2 This utility model provides an overflow well anti-overflow ash injection valve, including: an upper connector 1, a main body 2, and a lower connector 3. The upper connector 1, the main body 2, and the lower connector 3 are sequentially threaded together. The main body 2 is configured as a through-hole structure. The inner cavity of the main body 2 is provided with a conical lower one-way valve structure. The conical lower one-way valve structure includes a valve core 4, a large compression spring 5, and a pressure cap 6. The valve core 4 is slidably installed in the inner cavity of the main body 2. The pressure cap 6 is threaded to the bottom end of the main body 2. The large compression spring 5 is installed between the valve core 4 and the pressure cap 6. The upper part of the inner cavity of the main body 2 is provided with an inverted conical circular hole. The top end of the valve core 4 is provided with an outer conical surface and cooperates with the inverted conical circular hole. The pressure cap 6 has an axially opened eyelet. The valve core 4 is configured as a through-hole structure, and the inner cavity of the valve core 4 is provided with a constant pressure upper one-way valve structure 7. The constant pressure upper one-way valve structure 7 allows liquid to flow unidirectionally from bottom to top from the inner cavity of the valve core 4.

[0017] In one embodiment of this utility model, a sealing ring 8 is provided at the connection between the main body 2 and the upper connector 1 and the lower connector 3.

[0018] In one embodiment of this utility model, the valve core 4 is provided with a stop portion near the bottom outer wall, and the large compression spring 5 is installed between the stop portion and the pressure cap 6.

[0019] In one embodiment of this utility model, the large compression spring 5 presses against the valve core 4 to maintain the normally closed state of the conical lower single-flow valve structure.

[0020] In one embodiment of this utility model, the constant pressure single-flow valve structure 7 includes a valve ball 9, a small compression spring 10, a bolt rod 11, and a pressure plate 12. The top end of the valve core 4 is provided with a conical valve seat, which cooperates with the valve ball 9. The small compression spring 10 is installed in the inner cavity of the valve core 4. The pressure plate 12 is slidably installed on the bottom end of the small compression spring 10. The two ends of the bolt rod 11 are respectively fixedly connected to the valve ball 9 and the pressure plate 12. The pressure plate 12 has holes opened axially.

[0021] In one embodiment of this utility model, the inner cavity of the valve core 4 is a circular hole, and the inner diameter of the circular hole is larger than the minimum through hole of the conical valve seat.

[0022] In one embodiment of this utility model, an adjusting pad 13 is installed near the end of the conical valve seat of the circular hole, and a small compression spring 10 is installed between the adjusting pad 13 and the pressure plate 12.

[0023] In one embodiment of this utility model, the preload of the small compression spring 10 is adjusted by increasing or decreasing the thickness or number of the adjusting pad 13, thereby controlling the opening pressure of the valve ball 9.

[0024] The above are merely preferred embodiments of this utility model, but the scope of protection of this utility model is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this utility model, based on the technical solution and inventive concept of this utility model, should be included within the scope of protection of this utility model.

Claims

1. An overflow well anti-overflow ash injection valve, characterized in that, include: The upper connector (1), the main body (2), and the lower connector (3) are connected by threads in sequence. The main body (2) is designed as a through-hole structure. The inner cavity of the main body (2) is provided with a conical bottom flow valve structure. The conical bottom flow valve structure includes a valve core (4), a large compression spring (5), and a pressure cap (6). The valve core (4) is slidably installed in the inner cavity of the main body (2). The pressure cap (6) is threaded to the bottom end of the main body (2). A compression spring (5) is installed between the valve core (4) and the pressure cap (6). The upper part of the inner cavity of the main body (2) is provided with an inverted conical round hole. The top of the valve core (4) is provided with an outer conical surface and cooperates with the inverted conical round hole. The pressure cap (6) is provided with an axial hole. The valve core (4) is provided with a through structure. The inner cavity of the valve core (4) is provided with a constant pressure upper single flow valve structure (7). The constant pressure upper single flow valve structure (7) allows liquid to flow unidirectionally from bottom to top from the inner cavity of the valve core (4).

2. The overflow well anti-overflow ash injection valve according to claim 1, characterized in that: Sealing rings (8) are provided at the connection points between the main body (2) and the upper connector (1) and the lower connector (3).

3. The overflow well anti-overflow ash injection valve according to claim 1, characterized in that: The valve core (4) has a stop part near the bottom outer wall, and the large compression spring (5) is installed between the stop part and the pressure cap (6).

4. The overflow well anti-overflow ash injection valve according to claim 1, characterized in that: The large compression spring (5) presses against the valve core (4) to maintain the normally closed state of the conical lower single-flow valve structure.

5. The overflow well anti-overflow ash injection valve according to claim 1, characterized in that: The constant pressure single-flow valve structure (7) includes a valve ball (9), a small compression spring (10), a bolt rod (11), and a pressure plate (12). The top of the valve core (4) is provided with a conical valve seat, which cooperates with the valve ball (9). The small compression spring (10) is installed in the inner cavity of the valve core (4). The pressure plate (12) is slidably installed on the bottom end of the small compression spring (10). The two ends of the bolt rod (11) are fixedly connected to the valve ball (9) and the pressure plate (12) respectively. The pressure plate (12) has holes opened axially.

6. The overflow well anti-overflow ash injection valve according to claim 5, characterized in that: The inner cavity of the valve core (4) is a circular hole, and the inner diameter of the circular hole is larger than the minimum through hole of the conical valve seat.

7. The overflow well anti-overflow ash injection valve according to claim 6, characterized in that: An adjusting pad (13) is installed near the end of the conical valve seat in the circular hole, and a small compression spring (10) is installed between the adjusting pad (13) and the pressure plate (12).

8. The overflow well anti-overflow ash injection valve according to claim 7, characterized in that: The preload of the small spring (10) can be adjusted by increasing or decreasing the thickness or number of the adjusting pad (13), thereby controlling the opening pressure of the valve ball (9).

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