Cement injection valve easy to drill and grind

Abstract

The cement injection valve easy to drill and grind comprises an outer sleeve, an inner sliding sleeve vulcanization assembly, a screen pipe and a non-return vulcanization assembly, the outer sleeve is provided with a first through hole, the inner sliding sleeve vulcanization assembly is arranged in the outer sleeve in a sliding and sleeved mode and provided with a second through hole, the screen pipe is fixedly arranged in the inner sliding sleeve vulcanization assembly in a sleeved mode and provided with a third through hole, and the non-return vulcanization assembly is provided with a second through hole. A piston cavity is formed between the second through hole and the third through hole, a piston is arranged in the piston cavity in a sliding and sleeved mode, the non-return vulcanization assembly is located in the piston cavity and adsorbed to the third through hole, a cement injection valve structure is formed through the arrangement of the first through hole, the second through hole, the third through hole and the piston, and through the arrangement of the non-return vulcanization assembly, cement injection is achieved. By means of the non-return vulcanization assembly, cement paste on the inner side of the screen pipe can easily enter the piston cavity, however, external chippings and cement paste cannot enter the screen pipe through the non-return vulcanization assembly in the well cementation process, the protection effect is achieved, a plurality of outer sleeves and cement injection valve bodies are not needed in the whole cement well cementation process, and the manufacturing cost and the maintenance cost are effectively reduced.

Description

Technical Field

[0001] This utility model relates to the field of oil and gas well development technology, specifically to a cement injection valve that is easy to drill and grind. Background Technology

[0002] In the early days of the petroleum industry, the production life of oil and gas wells was relatively short, largely due to insufficient wellbore stability and insecure casing fixation. To extend the production life of oil and gas wells, an effective cementing method was needed to ensure a stable connection between the casing and the wellbore. Cement injection valves were developed to address this need. By injecting cement slurry into the annulus between the casing and the wellbore through the cement injection valve, the stability of the wellbore and the fixing effect of the casing can be greatly improved, thereby extending the production life of oil and gas wells and meeting the needs of long-term stable production in the petroleum industry. For example, the utility model patent CN202706982U, entitled "A Reinforcement and Support Device for Oilfield Well Pipelines," describes a double-layer combined casing protection system with an additional cement stone layer in the middle, designed for oilfield wells in the context of ultra-high pressure and external extrusion formations. This system can resist the external extrusion forces to a certain extent. The number of outer casings ranges from 1 to 20, with each outer casing connected to the oilfield pipeline at both ends via a cement injection valve. The specific number of outer casings required can be determined based on the length of the oilfield pipeline and the geographical conditions of the region.

[0003] However, the large number of outer casings and cementing valve bodies results in high manufacturing and maintenance costs for cementing. Utility Model Content

[0004] The purpose of this utility model is to overcome the above-mentioned technical deficiencies and propose a cementing valve that is easy to drill and grind, thus solving the technical problem that the large number of outer casing and cementing valve body in the existing technology leads to high manufacturing and maintenance costs for cementing.

[0005] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0006] This utility model provides an easy-to-drill cement injection valve, including an outer sleeve, an inner sliding sleeve vulcanization assembly, a screen tube, and a check valve vulcanization assembly. The outer sleeve has a first through hole. The inner sliding sleeve vulcanization assembly is slidably sleeved inside the outer sleeve and has a second through hole. The screen tube is fixedly sleeved inside the inner sliding sleeve vulcanization assembly and has a third through hole. A piston chamber is formed between the second through hole and the third through hole. A piston is slidably sleeved inside the piston chamber. The check valve vulcanization assembly is located in the piston chamber and is adsorbed onto the third through hole.

[0007] In some embodiments, the inner wall of the outer sleeve is embedded with a locking ring, and the top end of the inner sliding sleeve vulcanization assembly is connected to a locking ring seat, wherein the locking ring meshes with the locking ring seat.

[0008] In some embodiments, a sealing block is provided between the inner sliding sleeve vulcanization assembly and the outer sleeve.

[0009] In some embodiments, a first shear pin is provided between the piston and the screen tube.

[0010] In some embodiments, a second shear pin is provided between the inner sliding sleeve vulcanization assembly and the outer sleeve.

[0011] In some embodiments, the inner wall of the outer sleeve is provided with a guide pin, and the outer wall of the inner sliding sleeve vulcanization assembly is provided with a sliding groove, and the guide pin is slidably embedded in the sliding groove.

[0012] In some embodiments, a locking cap is installed at the bottom end of the screen tube.

[0013] In some embodiments, a cap is installed on the first through hole.

[0014] In some embodiments, an upper connector is mounted on the top end of the outer tube.

[0015] In some embodiments, a lower connector is installed at the bottom end of the outer tube.

[0016] Compared with the prior art, the present invention provides an easy-to-drill cement injection valve. The valve structure for cement injection is formed by the arrangement of a first through hole, a second through hole, a third through hole and a piston. The setting of the check vulcanization assembly allows cement slurry inside the screen tube to easily enter the piston chamber. However, during the cementing process, external debris and cement slurry cannot enter the screen tube through the check vulcanization assembly, thus playing a protective role. The entire cement cementing process does not require multiple outer sleeves and cement injection valve bodies, effectively reducing manufacturing and maintenance costs. Attached Figure Description

[0017] Figure 1 This is an initial structural schematic diagram of a cement injection valve that is easy to drill and grind, provided by an embodiment of this utility model;

[0018] Figure 2 This is a schematic diagram of a structure for opening a cement injection valve that is easy to drill and grind, according to an embodiment of this utility model;

[0019] Figure 3 This is a schematic diagram of a structure for closing a cement injection valve that is easy to drill and grind, according to an embodiment of this utility model.

[0020] Explanation of reference numerals in the attached drawings: 1. Outer sleeve; 11. First through hole; 111. Cap; 12. Locking ring; 13. Second shear pin; 14. Guide pin; 2. Inner sliding sleeve vulcanization assembly; 21. Second through hole; 22. Locking ring seat; 23. Sealing block; 24. Slide groove; 3. Screen tube; 31. Third through hole; 32. Piston chamber; 33. Piston; 331. First shear pin; 34. Locking cap; 4. Check valve vulcanization assembly; 5. Upper connector; 6. Lower connector. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for explaining the present utility model and are not intended to limit the present utility model.

[0022] To address the technical problem of high manufacturing and maintenance costs in cementing due to the large number of outer casings and cementing valve bodies, this invention provides an easy-to-drill cementing valve that can reduce manufacturing and maintenance costs.

[0023] It should be noted that the easy-to-drill cement injection valve described in this utility model is used in, but not limited to, oil and gas wells. For ease of explanation, this utility model only uses the application of an easy-to-drill cement injection valve in an oil and gas well as an example. The principle of applying an easy-to-drill cement injection valve to other types of equipment is essentially the same as that applied to oil and gas wells, and will not be described in detail here.

[0024] Please see Figure 1 - Figure 3 ,in Figure 1 This is a schematic diagram of the structure of an easy-to-drill cement injection valve according to an embodiment of the present invention. The easy-to-drill cement injection valve includes an outer sleeve 1, an inner sliding sleeve vulcanization assembly 2, a screen tube 3, and a check vulcanization assembly 4. The outer sleeve 1 has a first through hole 11. The inner sliding sleeve vulcanization assembly 2 is slidably sleeved in the outer sleeve 1 and has a second through hole 21. The screen tube 3 is fixedly sleeved in the inner sliding sleeve vulcanization assembly 2 and has a third through hole 31. A piston cavity 32 is formed between the second through hole 21 and the third through hole 31. A piston 33 is slidably sleeved in the piston cavity 32. The check vulcanization assembly 4 is located in the piston cavity 32 and is adsorbed into the third through hole 31.

[0025] In this embodiment, the first through hole 11, the second through hole 21, the third through hole 31 and the piston 33 constitute the valve structure for cement injection. The check valve assembly 4 allows cement slurry inside the screen pipe 3 to easily enter the piston chamber 32. However, during the cementing process, external debris and cement slurry cannot enter the screen pipe 3 through the check valve assembly 4, thus providing protection. The entire cement cementing process does not require multiple outer sleeves 1 and cement injection valve bodies, effectively reducing manufacturing and maintenance costs.

[0026] The cementing valve is positioned within the wellbore according to the design of the tubing string. The upper part can generally be connected to the hanger, packer, etc., and the lower part can be connected to the tubing string, etc. Before cementing, a ball is thrown into the tool at the bottom of the cementing valve to seal the upper space. After the hydraulic pump pressurizes, when the pressure reaches the starting pressure, the piston 33 moves downward and the external channel opens, achieving the purpose of cementing. When it is necessary to close the cementing valve, large and small rubber plugs can be inserted into the upper part. After the pressure reaches the threshold, the channel closes and double O-rings are sealed. The internal components of the outer casing 1 are made of drillable material, which can be removed with a drill bit after cementing is completed.

[0027] Furthermore, the check vulcanizing assembly 4 is a rubber-like object connected to the screen pipe 3 via shear pins. The check vulcanizing assembly 4 acts as a one-way valve. After the cement slurry is injected into the downhole annular space, once the injection pressure is stopped, without the check vulcanizing assembly 4 to prevent it, the cement slurry may flow backward due to changes in downhole pressure or other factors. The check vulcanizing assembly 4 ensures that the cement slurry can only flow forward. Moreover, after the cement injection work is completed, subsequent operations may cause pressure fluctuations. The check vulcanizing assembly 4 can prevent external liquids or other substances from flowing back into the screen pipe 3, thus providing protection.

[0028] Furthermore, the outer casing 1 and the cementing valve are made of high-strength alloy steel, while the internal drilling and grinding parts are made of aluminum alloy or special rubber materials. During cementing operations, cement slurry is injected into the well under certain pressure. As the main pressure-bearing components, the outer casing 1 and the cementing valve are made of high-strength alloy steel, which can effectively resist this high pressure. The relatively low density of aluminum alloy makes the internal drilling and grinding parts of the cementing valve lighter in weight, while still meeting the requirements for hardness and load-bearing capacity. In addition, aluminum alloy is easy to be removed by the PDC drill bit. The reasonable combination of materials ensures that cementing operations can be carried out smoothly under complex well conditions.

[0029] In one embodiment, a locking ring 12 is embedded in the inner wall of the outer sleeve 1, and a locking ring seat 22 is connected to the top of the inner sliding sleeve vulcanization assembly 2, with the locking ring 12 meshing with the locking ring seat 22.

[0030] In this embodiment, the locking ring 12 and the locking ring seat 22 form an anti-backward mechanism, replacing the traditional C-ring release structure. The locking ring can keep the teeth locked throughout the entire process of the piston 33 moving downward to open the cement injection valve. It can prevent backward at any time and prevent the outer sleeve 1 from being tightly connected to the internal drillable part when encountering obstruction or jamming, or when the O-ring has not yet reached the opening position of the cement injection valve or has already reached the opening position of the cement injection valve. In other words, it avoids the phenomenon that the cement injection valve cannot be closed normally because the C-ring structure has not reached the jamming groove.

[0031] In one embodiment, a sealing block 23 is provided between the inner sliding sleeve vulcanization assembly 2 and the outer sleeve 1.

[0032] In this embodiment, both ends of the inner sliding sleeve vulcanization assembly 2 are sealed with double O-rings, which can better prevent the leakage of media such as cement slurry. At the same time, a sealing block 23 is provided. The sealing block 23 is made of rubber material to ensure that when the inner sliding sleeve vulcanization assembly 2 moves downward to close the cement injection valve, the O-ring and the back ring are at the opening of the cement injection valve. The sealing block 23 can immediately take over the work to prevent cement slurry leakage. The sealing block 23 and the O-ring at the rear end still achieve a double sealing effect, which improves the sealing reliability of the inner sliding sleeve vulcanization assembly 2 as a whole.

[0033] In one embodiment, a first shear pin 331 is provided between the piston 33 and the screen tube 3.

[0034] In this embodiment, the function of the first shear pin 331 is to fix the piston 33. After the hydraulic pump pressurizes, when the pressure reaches the starting pressure, the first shear pin 331 connected to the piston 33 is sheared, the piston 33 moves downward, the external channel is opened, and the purpose of cementing the well is achieved.

[0035] In one embodiment, a second shear pin 13 is provided between the inner sliding sleeve vulcanization assembly 2 and the outer sleeve 1.

[0036] In this embodiment, the function of the second shear pin 13 is to fix the inner sliding sleeve vulcanization assembly 2 and the outer sleeve 1. When the cement injection valve is closed, a rubber plug is inserted into the upper part of the cement injection valve to form a sealed space inside the cement injection valve. If the upper part continues to be pressurized, the pressure in the space above the rubber plug of the cement injection valve will be greater than the pressure in the overall space of the cement injection valve screen tube 3 and the inner sliding sleeve vulcanization assembly 2. Due to the pressure difference, the locking ring seat 22 and the inner sliding sleeve vulcanization assembly 2 are connected by threads and move downward together, shearing the second shear pin 13 connected to the outer sleeve 1. The first through hole 11 is no longer aligned with the second through hole 21, so the cement injection valve gradually closes.

[0037] In one embodiment, the inner wall of the outer sleeve 1 is provided with a guide pin 14, and the outer wall of the inner sliding sleeve vulcanization assembly 2 is provided with a groove 24, and the guide pin 14 is slidably embedded in the groove 24.

[0038] In one embodiment, a locking cap 34 is installed at the bottom end of the screen tube 3.

[0039] In this embodiment, multiple structural designs incorporate anti-rotation features. The outer sleeve 1 is equipped with a guide pin 14 that engages with the vulcanization assembly of the sliding sleeve. The screen tube 3 has a left-hand thread, while the locking cap 34 has a right-hand thread that can resist the downward movement of the screen tube 3. These special structures effectively prevent the cement injection valve from rotating with the drill bit when the drill bit is lowered to drill the cement injection valve. The valve is firmly fixed in the appropriate position, improving drilling efficiency while ensuring the sealing and normal operation of the cement injection valve.

[0040] In one embodiment, a cap 111 is installed in the first through hole 11.

[0041] In this embodiment, the cap 111 is used to protect the first through hole 11. Before cementing, a pre-filled fluid will open the cap 111 to facilitate cement entry into the annulus.

[0042] In one embodiment, an upper connector 5 is installed at the top end of the outer tube 1.

[0043] In this embodiment, the upper connector 5 is used to connect the hanger, packer, etc.

[0044] In one embodiment, a lower connector 6 is installed at the bottom end of the outer sleeve 1.

[0045] In this embodiment, the lower connector 6 is used for tubing, etc.

[0046] To better understand this utility model, the following is combined with... Figures 1 to 3 The technical solution of this utility model is described in detail below:

[0047] When the cement injection valve is lowered, it is in the closed state. At this time, a ball seal is thrown into the tool at the lower part of the cement injection valve, and the upper part of the hydraulic pump is pressurized. The pressure enters the piston chamber 32 through the third through hole 31 on the screen pipe 3. The check flue assembly 4 is connected to the screen pipe 3 through the shear pin. When the pre-fluid enters the piston chamber 32 from the third through hole 31, the check flue assembly 4 is lifted up, and the piston chamber 32 is filled with pressurized liquid. When the pressure reaches the shear limit of the first shear pin 331, the first shear pin 331 is sheared, and the piston 33 begins to move downward. When the piston 33 moves to the cement injection valve channel where the cap 111 is located, the pre-fluid flows out of the channel, opens the cap 111, and completes the opening state of the cement injection valve. Then, cementing is performed for well cementing.

[0048] When closing the cement injection valve, insert a rubber plug into the upper part of the cement injection valve to form a sealed space inside the cement injection valve. Continue to pressurize the upper part, and the pressure in the space above the rubber plug of the cement injection valve will be greater than the pressure in the overall space of the cement injection valve screen tube 3 and the inner sliding sleeve vulcanization assembly 2. Due to the pressure difference, the locking ring seat 22 and the inner sliding sleeve vulcanization assembly 2 are connected by threads and move downward together, cutting off the second shearing pin 13 connected to the outer sleeve 1. The first through hole 11 is no longer aligned with the second through hole 21, so the cement injection valve gradually closes. When the O-ring and the O-ring back ring contact the outer sleeve 1 behind the first through hole 11 and re-form a seal, the cement injection valve is completely closed, and the entire cement injection work is completed. At this time, the drilling tool assembly can be lowered to drill away the drillable part of the aluminum alloy material inside the cement injection valve.

[0049] The specific embodiments of this utility model described above do not constitute a limitation on the scope of protection of this utility model. Any other corresponding changes and modifications made based on the technical concept of this utility model should be included within the scope of protection of the claims of this utility model.

Claims

1. An easy-to-drill millout cement valve characterized by, The application relates to a vulcanization assembly, which comprises the following parts: an outer sleeve provided with a first through hole; an inner sliding sleeve vulcanization assembly which is slidably sleeved in the outer sleeve and is provided with a second through hole; a screen pipe which is fixedly sleeved in the inner sliding sleeve vulcanization assembly and is provided with a third through hole, a piston cavity is arranged between the second through hole and the third through hole, and a piston is slidably sleeved in the piston cavity; and a check vulcanization assembly which is arranged in the piston cavity and is adsorbed to the third through hole.

2. An easy-to-drill millable cement valve according to claim 1, characterized in that The inner wall of the outer sleeve is embedded with a lock ring, the top end of the inner sliding sleeve vulcanization assembly is connected with a lock ring seat, and the lock ring is meshed with the lock ring seat.

3. An easy-to-drill millable cement valve according to claim 1, wherein, Sealing blocks are arranged between the inner sliding sleeve vulcanization assembly and the outer sleeve.

4. An easy-to-drill millable cement valve according to claim 1, wherein, First shearing pins are arranged between the piston and the screen pipe.

5. An easy-to-drill millable cement valve according to claim 1, wherein, Second shearing pins are arranged between the inner sliding sleeve vulcanization assembly and the outer sleeve.

6. An easy-to-drill millable cement valve according to claim 1, wherein, The inner wall of the outer sleeve is provided with a guide pin, and the outer wall of the inner sliding sleeve vulcanization assembly is provided with a sliding groove, the guide pin is slidably embedded in the sliding groove.

7. An easy-to-drill millable cement valve according to claim 1, wherein, A lock cap is arranged at the bottom end of the screen pipe.

8. An easy-to-drill millable cement valve according to claim 1, wherein, A cover cap is arranged at the first through hole.

9. An easy-to-drill millable cement valve according to claim 1, wherein, An upper joint is arranged at the top end of the outer sleeve.

10. The easy-to-drill out cement valve of claim 1, wherein, A lower joint is arranged at the bottom end of the outer sleeve.

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