Vibration reduction and looseness prevention device for underground separated layer water injection packer pipe column

Abstract

The invention relates to the technical field of water injection packers, and discloses a vibration reduction and looseness prevention device for an underground separated layer water injection packer pipe column, which comprises an expansion assembly, the expansion assembly comprises an expansion sleeve body, the expansion sleeve body is connected between two groups of flexible pipes, and one ends, far away from the expansion sleeve body, of the two groups of flexible pipes are respectively communicated with the water injection packer pipe column and a water injection pipe; a guide hole penetrating through the expansion sleeve body is formed in the expansion sleeve body in the radial direction, and an expansion assembly is installed at the guide hole. An expansion block is arranged on the peripheral side of the expansion sleeve body, the inner side of the expansion block is connected with an expansion assembly, a surrounding extension spring is further arranged on the peripheral side of the expansion sleeve body, and the surrounding extension spring is wound on the outer side of the expansion block; the flexible pipe can well block vibration transmitted by the water injection pipe at the upper end, and the expansion assembly can fix the other end of the flexible pipe, so that vibration borne by the underground separated layer water injection packer pipe column is greatly reduced, stability and sealing of the underground separated layer water injection packer pipe column are guaranteed, separated layer water injection can be normally carried out, and production efficiency is improved. Therefore, the oil extraction rate of the oil well is improved.

Description

Technical Field

[0001] The invention relates to the technical field of water injection packers, in particular to a vibration reduction and loosening prevention device for a downhole stratified water injection packer pipe column. Background Art

[0002] After an oil field is put into development, as the exploitation time increases, the energy of the oil layer itself will be continuously consumed, causing the oil layer pressure to continue to drop, the viscosity to increase, the oil well production to be greatly reduced, and even the spraying and production to stop, resulting in a large amount of dead oil remaining underground that cannot be extracted. In order to make up for the problem of reduced underground oil layer pressure after crude oil is extracted, water is usually injected into the oil field to maintain the formation pressure, thereby increasing the oil recovery rate. Therefore, stratified water injection has become an important means to solve the unreasonable distribution of formation pressure during oil field development, maintain long-term stable and high production of oil fields, and improve the recovery rate.

[0003] However, when high-pressure water is pumped into the downhole stratified water injection packer string through the water injection pipe, the "fluid pulsation" in the water injection pipe will cause the water injection pipe to vibrate. When the pulsation frequency is consistent with the natural frequency of the water injection pipe structure, the water injection pipe will resonate, resulting in violent vibration. The violent vibration will loosen or even damage the downhole stratified water injection packer string, resulting in a significant reduction in water injection capacity, making it impossible for oil well production to proceed normally. Summary of the invention

[0004] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a vibration-damping and loosening-proof device for a downhole stratified water injection packer string. The flexible tube can effectively block the vibration transmitted from the upper water injection pipe, and the expansion assembly can fix the other end of the flexible tube, so that the vibration of the downhole stratified water injection packer string is greatly reduced, thereby ensuring the stability and sealing of the downhole stratified water injection packer string, allowing the stratified water injection to proceed normally, thereby improving the oil recovery rate of the oil well.

[0005] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0006] A vibration-damping and anti-loosening device for a downhole stratified water injection packer pipe column comprises an expansion assembly, the expansion assembly comprises an expansion sleeve body, the expansion sleeve body is connected between two groups of flexible tubes, and the two groups of flexible tubes are respectively connected to the water injection packer pipe column and the water injection pipe at one end away from the expansion sleeve body; a guide hole penetrating the expansion sleeve body is radially provided on the expansion sleeve body, and the expansion assembly is installed at the guide hole; an expansion block is provided on the peripheral side of the expansion sleeve body, and the inner side of the expansion block is connected to the expansion assembly, and a surrounding tension spring is also provided on the peripheral side of the expansion sleeve body, and the surrounding tension spring is wound around the outer side of the expansion block.

[0007] As a further implementation, the expansion sleeve body is axially provided with a flow channel, the two groups of flexible tubes are respectively a first flexible tube and a second flexible tube, and one end of the two flexible tubes is connected to the expansion sleeve body through a joint.

[0008] As a further implementation method, the guide holes are arranged in several groups along the circumferential direction on the expansion sleeve body, and several groups of slide grooves are arranged correspondingly along the axial direction on the circumferential side of the expansion sleeve body. The outer end of the guide hole extends to the slide groove to achieve communication between the inside and outside of the expansion sleeve body.

[0009] As a further implementation, the expansion assembly includes a guide shaft, the expansion block is slidably installed in the slide groove, the outer end of the guide shaft is fixedly connected to the expansion block through the thread root, and the guide shaft is slidably matched with the guide hole.

[0010] As a further implementation, the outer side of the expansion block is provided with linear grooves arranged in parallel along the length direction; the inner end of the guide shaft is provided with an annular groove along the annular direction, and a sealing ring is provided at the annular groove.

[0011] As a further implementation, the length of the expansion block is smaller than the length of the slide slot.

[0012] As a further implementation, an annular groove is provided on the circumferential side of the expansion sleeve body, the surrounding tension spring is wound around the annular groove, and the tightening block is located on the inner side of the surrounding tension spring.

[0013] As a further implementation, the annular groove and the guide hole are arranged in an alternating manner.

[0014] As a further implementation, the flexible tube comprises, from inside to outside, an inner tube, a steel belt layer, a steel belt coating layer, an aramid tensile layer and an outer coating layer.

[0015] As a further implementation method, the end of the flexible tube is provided with a joint, which includes a joint inner core and a joint outer body. The joint inner core is located on the inner side of the flexible tube, and the joint outer body is located on the outer side of the flexible tube. The joint inner core and the end of the joint outer body extend beyond the end of the flexible tube and are clamped.

[0016] The beneficial effects of the present invention are as follows:

[0017] 1. The flexible pipe of the present invention can well block the vibration transmitted from the upper water injection pipe, and the expansion assembly can fix the other end of the flexible pipe, so that the vibration of the downhole stratified water injection packer string is greatly reduced, ensuring the stability and sealing of the downhole stratified water injection packer string, so that the stratified water injection can be carried out normally, thereby improving the oil recovery rate of the oil well.

[0018] 2. The expansion assembly of the present invention is connected between two groups of flexible pipes. The flexible pipes can reduce vibration by their own flexibility, and the expansion assembly can achieve complete fixation between the ends of the two groups of flexible pipes that are close to each other and the well wall, further reducing the risk caused by vibration.

[0019] 3. When the whole device is pulled up after the stratified water injection is completed, if a special situation occurs that causes the expansion block to get stuck and cannot be tightened, the pulling force can be increased to a set tonnage, and the connecting bolts between the guide shaft and the expansion block can be cut off. The expansion block will be firmly tightened on the expansion sleeve or the outer wall of the flexible pipe under the action of the surrounding tension spring, thereby avoiding the falling of parts and causing the oil well to be blocked. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0021] Figure 1 Schematic diagram of the overall structure of the vibration reduction and anti-loosening device in an embodiment of the present invention;

[0022] Figure 2 yes Figure 1 Schematic diagram of the middle AA section;

[0023] Figure 3 is a schematic diagram of the overall structure of the expansion assembly in an embodiment of the present invention;

[0024] Figure 4 is a schematic cross-sectional view of the overall structure of the expansion assembly in an embodiment of the present invention;

[0025] Figure 5 It is a schematic structural diagram of an expansion sleeve body in an embodiment of the present invention;

[0026] Figure 6 yes Figure 5 AA section diagram of the mid-expansion sleeve;

[0027] Figure 7 is a schematic structural diagram of a guide shaft in an embodiment of the present invention;

[0028] Figure 8 is a schematic structural diagram of a flexible pipe in an embodiment of the present invention;

[0029] Fig. 9 It is a schematic diagram of the structure of the expansion block and the guide shaft in the embodiment of the present invention.

[0030] In the figure: the distances or sizes between parts are exaggerated to show the positions of various parts, and the schematic diagram is for reference only.

[0031] Wherein: 1. flexible tube, 2. expansion sleeve, 3. expansion block, 4. guide shaft, 5. surrounding tension spring, 6. sealing ring; 11. joint inner core, 12. joint outer shell, 13. outer coating layer, 14. aramid tensile layer, 15. steel belt coating layer, 16. steel belt layer, 17. inner tube; 21. slide groove, 22. guide hole, 23. annular groove; 41. annular groove, 42. thread root. DETAILED DESCRIPTION

[0032] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0033] Embodiment 1

[0034] In a typical embodiment of the present invention, reference is made to Figure 1-Figure 9 As shown, a vibration reduction and anti-loosening device for a downhole stratified water injection packer pipe string includes two groups of flexible pipes and a group of expansion components. The expansion components are connected between the two groups of flexible pipes. The expansion components include an expansion sleeve. One end of the two groups of flexible pipes away from the expansion sleeve is respectively connected to the water injection packer pipe string and the water injection pipe. The expansion components are expanded on the well wall to fix one end of the flexible pipe, so that the vibration of the downhole stratified water injection packer pipe string is greatly reduced.

[0035] The two groups of flexible tubes are respectively the first flexible tube and the second flexible tube, and one end of the two flexible tubes close to the expansion sleeve is connected to the expansion sleeve through a joint. Figure 1 Taking the viewing direction as an example, the left side of the expansion sleeve is connected to one end of the first flexible tube, and the right side is connected to one end of the second flexible tube. The other end of the second flexible tube is connected to the packer string through a joint, and the other end of the first flexible tube is connected to the water injection pipe through a joint.

[0036] like Figure 8 As shown, the flexible tube comprises, from inside to outside, an inner tube 17, a steel belt layer 16, a steel belt coating layer 15, an aramid tensile layer 14 and an outer coating layer 13, and the flexible tube has great bending flexibility.

[0037] The upper end of the first flexible pipe 1 is connected to the water injection pipe through a joint, and its own flexibility is used to block the vibration transmitted from the upper water injection pipe. The lower end of the second flexible pipe 2 is connected to the downhole stratified water injection packer string through a joint, further blocking the vibration from being transmitted to the downhole stratified water injection packer string.

[0038] Preferably, the layers of the flexible pipe are non-bonded, and the steel belt layer 16 is laid on the outer periphery of the inner pipe using a Z-shaped steel belt, with a laying angle greater than 70° and less than 90°. The laying angle is the angle between the steel belt and the horizontal plane on the cross section of the flexible pipe, such as Figure 8 As shown, the preferred laying angle is 85°. The steel belt layer 16 bears the main internal and external pressures. The steel belt layer is formed by winding multiple steel belts, and adjacent steel belts are firmly locked together. This interlocking structure allows the steel belts to rotate, so the steel belt layer can bend significantly.

[0039] The aramid tensile layer 14 is obtained by bidirectional winding of aramid fiber ropes, with a small laying angle, usually less than 35°, and bears the main axial tension. The steel belt coating layer 15 is sleeved on the steel belt layer 16 to reduce the friction between the steel belt layer 15 and the aramid tensile layer 14. The inner tube 17 is used to transport the fluid in the tube and protect the flexible tube structure from erosion and damage. The outer coating layer 13 is also used to protect the flexible tube structure from erosion and damage. In addition to having a strong load-bearing capacity, the flexible tube as a whole also has great flexibility.

[0040] The inner tube 17, the outer coating layer 13 and the steel belt coating layer 15 of the flexible tube of this embodiment are made of oil-resistant rubber and have strong corrosion resistance.

[0041] Joints are provided at both ends of the first flexible tube and the second flexible tube, and the joints include a joint inner core 11 and a joint outer shell 12. One end of the joint inner core 11 extends into the inner side of the inner tube 17 and abuts against the end of the flexible tube through a step structure. One end of the joint outer shell is sleeved on the outside of the outer covering layer 13. The joint inner core and the end of the joint outer shell are located outside the end of the flexible tube and are clamped and fixed to each other.

[0042] like Figure 2-Figure 7 As shown, the expansion sleeve body 2 is an annular cylindrical structure, and a flow channel is axially arranged in the expansion sleeve body 2. The ends of the first flexible tube 1 and the second flexible tube 1 are connected to the ends of the flow channel of the expansion sleeve body through joints to achieve communication between the expansion sleeve body 2 and the flexible tube 1. The expansion sleeve body 2 and the end joints of the flexible tube are both made of metal, and the flexible tube 1 and the expansion sleeve body 2 can be fixedly connected by threaded connection or welding.

[0043] A guide hole 22 is radially provided on the expansion sleeve body and penetrates the expansion sleeve body, and an expansion component is installed at the guide hole 22; a tightening block 3 is provided on the peripheral side of the expansion sleeve body, and the inner side of the tightening block 3 is connected to the expansion component; a surrounding tension spring 5 is also provided on the peripheral side of the expansion sleeve body 2, and the surrounding tension spring 5 is wound around the outer side of the tightening block 3.

[0044] like Figure 2 As shown, the guide holes 22 are arranged in a plurality of groups along the circumferential direction on the expansion sleeve body, and a plurality of slide grooves 21 are arranged correspondingly along the axial direction on the circumferential side of the expansion sleeve body. The outer ends of the guide holes 22 extend to the slide grooves 21 to achieve communication between the inside and outside of the expansion sleeve body 2.

[0045] Specifically, three groups of guide holes 22 are arranged in the circumferential direction on the expansion sleeve body 2, each group includes two guide holes 22 and is arranged along the length direction of the expansion sleeve body, and three groups of slide grooves 21 are correspondingly arranged along the axial direction on the circumferential side of the expansion sleeve body 2, such as Figure 2 and Figure 5As shown, the guide hole 22 is a through-groove structure, the inner end of which extends to the internal flow channel of the expansion sleeve 2, and the outer end thereof passes through the expansion sleeve 2 and is located at the slide groove 21. The guide hole 22 realizes the communication between the internal flow channel of the expansion sleeve 2 and the outside of the expansion sleeve 2.

[0046] like Figure 3 As shown, the length of the slide groove 21 is the same as the length of the expansion sleeve 2, the expansion block 3 is slidably installed in the slide groove 21, and the length of the expansion block 3 is smaller than the length of the slide groove 21 to allow the expansion block 3 to slide inside the slide groove 21 in special circumstances, such as when the guide shaft and the expansion block 3 are released.

[0047] like Figure 7 As shown, the expansion assembly includes a guide shaft 4, a thread root 42 is provided at the top of the guide shaft 4, and the guide shaft 4 is threadedly fixedly connected to the expansion block 3 through the thread root 42. Each expansion block 3 is vertically fixedly connected to two guide shafts 4, such as Fig. 9 shown.

[0048] The guide shaft 4 has a circular cross section and is used to be installed in the guide hole 22 so that the guide shaft 4 and the guide hole 22 are slidably matched. During installation, the guide shaft 4 is first threadedly fixedly connected with the expansion block 3, and then the guide shaft 4 is aligned with the guide hole 22 and inserted, and the expansion block 3 is placed in the slide groove 21.

[0049] The bottom end of the guide shaft 4 after installation is located in the guide hole 22. The guide shaft 4 is provided with an annular groove 41 on the peripheral side near the bottom end, and a sealing ring 6 is provided at the annular groove 41. The sealing ring is used to seal the gap between the guide shaft 4 and the guide hole 22 to prevent liquid leakage. The annular groove 41 can be provided with two or more. The sealing ring 6 is a nitrile O-type sealing ring with a thickness of 1.5 to 2 mm.

[0050] like Figure 2 As shown, when the liquid flows into the flow channel at the expansion sleeve body 2, under the action of pressure, the expansion assembly-guide shaft 4 pushes the expansion block 3 to expand outward, thereby pressing the outer surface of the expansion block 3 against the well wall, achieving relative fixation of the expansion sleeve body 2 and the well wall, and then fixing one end of the flexible tube through the expansion assembly, thereby reducing vibration.

[0051] like Figure 3 As shown, the outer side of the expansion block 3 is provided with straight grooves arranged in parallel along the length direction to form straight lines, thereby increasing the friction between the expansion block and the well wall.

[0052] like Figure 3-Figure 6 As shown, a plurality of annular grooves 23 are provided on the circumferential side of the expansion sleeve body 2 for installing the surrounding tension spring 5. The surrounding tension spring 5 of this embodiment is wound on the annular groove 23, and the tightening block 3 is located on the inner side of the surrounding tension spring 5, and the tightening block 3 is tightened by the surrounding tension spring 5.

[0053] like Figure 6 As shown, in this embodiment, two annular grooves 23 are provided, and the positions of the annular grooves 23 and the guide holes 22 are staggered. In other preferred examples, three annular grooves 23 are provided, and the positions of the annular grooves 23 and the guide holes 22 are staggered, and each guide hole 22 is located between two adjacent annular grooves 23. Correspondingly, an arc groove structure is provided on the expansion block 3 to cooperate with the surrounding tension spring 5, and the outer surface of the expansion block 3 is an arc surface, the purpose of which is to better contact with the well wall.

[0054] The guide shaft and the expansion block 3 are made of 42CrMo, which has high hardness and good wear resistance. The surrounding tension spring 5 is located in the annular groove 23 and can tighten the expansion block 3.

[0055] The first flexible tube uses its own flexibility to block the vibration from the upper water injection pipe, and the expansion assembly uses the internal water pressure to support the expansion block on the well wall, thereby fixing one end of the flexible tube 1. The second flexible tube uses its own flexibility to further block the vibration from above, thereby greatly reducing the loosening and damage of the underground stratified water injection packer string, ensuring the smooth progress of stratified water injection.

[0056] When performing stratified water injection, the guide shaft 4 expands and moves outward along the guide hole 22 of the expansion sleeve 2 under the action of internal water pressure. In order to prevent water from seeping out, the guide shaft 4 reserves a circle of annular grooves, and a circle of nitrile O-type sealing rings with a thickness of 1.5mm is placed on the grooves. The expansion block 3 is connected to the guide shaft 4 by straight-grained bolts. There are a total of 3 expansion blocks 3. They move outward under the push of the guide shaft 4 until they are supported on the well wall, thereby fixing one end of the flexible tube. The expansion sleeve 2 is sealed to prevent the fluid in the tube from seeping out. The surface of the expansion block 3 in contact with the well wall is serrated to improve the support stability.

[0057] Specifically, when the packer is lowered to a suitable position and the pressure is applied to seal the well, the guide shaft 4 pushes the expansion block 3 under the pressure difference between the inside and outside of the pipe, and expands to the well wall. The straight-grained structure of the contact surface plays a role in preventing loosening. After the expansion block 3 is expanded, during the normal water flow, the flexible pipe 1 made of rubber, steel belt and aramid plays a vibration reduction role, further ensuring that the packer will not loosen during use.

[0058] When the pipe needs to be lifted out of the well, the pressure difference between the inside and outside of the pipe is eliminated, and the guide shaft pulls the expansion block back under the action of the surrounding tension spring 5, and the packer can be released normally. If the expansion block 3 has a special situation and cannot be retracted, when the lifting force exceeds about 10 tons, the thread root 42 of the guide shaft 4 will be cut off, so that the expansion block 3 falls off. After falling off, under the action of the surrounding tension spring 5, the expansion block 3 shrinks and slides to the outer wall of the flexible pipe 1, and finally is pulled up with the flexible pipe 1.

[0059] During stratified water injection in this embodiment, the flexible tube can effectively block the vibration transmitted from the upper water injection tube, and the expansion assembly can fix the other end of the flexible tube, so that the vibration of the downhole stratified water injection packer string is greatly reduced, thereby ensuring the stability and sealing of the downhole stratified water injection packer string, allowing the stratified water injection to proceed normally, thereby improving the oil recovery rate of the oil well.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A vibration reduction and anti-loosening device for a downhole stratified water injection packer string, characterized in that: It includes an expansion assembly, which includes an expansion sleeve body. The expansion sleeve body is connected between two groups of flexible tubes. The ends of the two groups of flexible tubes away from the expansion sleeve body are respectively connected with the water injection packer pipe column and the water injection pipe; a guide hole that penetrates the expansion sleeve body is radially provided on the expansion sleeve body, and the expansion assembly is installed at the guide hole; an expansion block is provided on the peripheral side of the expansion sleeve body, and the inner side of the expansion block is connected to the expansion assembly. A surrounding tension spring is also provided on the peripheral side of the expansion sleeve body, and the surrounding tension spring is wound around the outside of the expansion block.

2. A vibration reduction and loosening prevention device for a downhole stratified water injection packer string according to claim 1, characterized in that: The expansion sleeve body is axially provided with a flow channel, and the two groups of flexible tubes are respectively a first flexible tube and a second flexible tube, and one end of the two flexible tubes is connected to the expansion sleeve body through a joint.

3. The vibration reduction and loosening prevention device for a downhole stratified water injection packer string according to claim 1, characterized in that: The guide holes are arranged in a plurality of groups along the circumferential direction on the expansion sleeve body, and a plurality of slide grooves are arranged correspondingly along the axial direction on the circumferential side of the expansion sleeve body. The outer ends of the guide holes extend to the slide grooves to achieve communication between the inside and outside of the expansion sleeve body.

4. A vibration reduction and loosening prevention device for a downhole stratified water injection packer string according to claim 3, characterized in that: The expansion assembly comprises a guide shaft, the expansion block is slidably mounted on the slide groove, the outer end of the guide shaft is fixedly connected to the expansion block through a threaded root, and the guide shaft is slidably matched with the guide hole.

5. A vibration reduction and anti-loosening device for a downhole stratified water injection packer string according to claim 4, characterized in that: The outer side of the expansion block is provided with linear grooves arranged in parallel along the length direction; the inner end of the guide shaft is provided with an annular groove along the annular direction, and a sealing ring is provided at the annular groove.

6. The vibration reduction and loosening prevention device for a downhole stratified water injection packer string according to claim 4, characterized in that: The length of the expansion block is smaller than the length of the sliding groove.

7. The vibration reduction and loosening prevention device for a downhole stratified water injection packer string according to claim 2, characterized in that: An annular groove is arranged on the peripheral side of the expansion sleeve body, the surrounding tension spring is wound on the annular groove, and the expansion block is located on the inner side of the surrounding tension spring.

8. The vibration reduction and loosening prevention device for a downhole stratified water injection packer string according to claim 7, characterized in that: The annular grooves and the guide holes are arranged in a staggered manner.

9. The vibration reduction and loosening prevention device for a downhole stratified water injection packer string according to claim 1, characterized in that: The flexible tube comprises, from inside to outside, an inner tube, a steel belt layer, a steel belt coating layer, an aramid tensile layer and an outer coating layer.

10. A vibration reduction and loosening prevention device for a downhole stratified water injection packer string according to claim 9, characterized in that: The end of the flexible pipe is provided with a joint, which includes a joint inner core and a joint outer body. The joint inner core is located inside the flexible pipe, and the joint outer body is located outside the flexible pipe. The joint inner core and the joint outer body end extend outside the flexible pipe end and are clamped.

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