A perforating bidirectional shock absorber based on energy-absorbing material and a shock absorption effect evaluation method

Abstract

The present application relates to the technical fields of oil and gas well oil pipe transmission perforation, in particular to a perforation bidirectional shock absorber based on energy-absorbing material and a shock absorption effect evaluation method, the bidirectional shock absorber comprises two energy-absorbing material elements respectively connected in series at both ends of a shock absorbing spring, one end of one of the energy-absorbing material elements is abutted against the end of an upper joint through an upper limiting gasket, and the other end of the other energy-absorbing material element is abutted against the end of a structure formed by the connection of a plug and a sliding shaft through a lower limiting gasket. Through the bidirectional shock absorber and the shock absorption effect evaluation method, the problem of poor absorption effect of low-frequency impact shock waves and poor bidirectional axial shock absorption effect generated during perforation can be effectively solved.

Description

Technical Field

[0001] This invention relates to the field of perforation technology for oil and gas well tubing, and in particular to a bidirectional perforation damper based on energy-absorbing materials and a method for evaluating its damping effect. Background Technology

[0002] During perforation testing operations, the perforator generates powerful low-frequency shock waves that propagate from the point of impact through the tubing connection, the well media, and the casing wall. Therefore, effective vibration reduction, damping, and isolation measures are necessary to prevent damage or breakage of the tubing and testing tools from these low-frequency shocks.

[0003] In the prior art, a Chinese utility model patent document with publication number CN205990903U and authorization announcement date of March 1, 2017, was proposed to solve the above-mentioned technical problems. The technical solution disclosed in the patent document is as follows: A longitudinal bidirectional shock absorber for oil and gas wells, comprising an upper connector, a central rod, a plug, a sliding shaft, a shock-absorbing spring, and an outer sleeve. The plug is sleeved on the outer wall of the sliding shaft, and a shear pin is provided between the plug and the sliding shaft. One end of the shock-absorbing spring is abutted against the end of the upper connector via an upper limit washer, and the other end of the shock-absorbing spring is abutted against the end of the structure formed by the connection of the plug and the sliding shaft via a lower limit washer. The outer sleeve is connected to the upper connector and the plug respectively, and is located between the upper connector and the plug. The central rod is located in the inner cavity formed by the connection of the upper connector and the sliding shaft, and the outer wall of the central rod is provided with two steps, one of which cooperates with the sliding shaft, and the other step cooperates with the upper limit washer.

[0004] The above technical solution will encounter the following problems in actual use: The above technical solution mainly uses springs to absorb impact vibration waves to achieve a damping effect, which can achieve the problem of tension damping to a certain extent. However, due to the high natural frequency of the spring, its absorption effect on low-frequency impact vibration waves is poor. The impact vibration waves generated during perforation have the largest pressure amplitude in the low-frequency range. The impact vibration waves in the low-frequency range have the greatest impact on the perforation string and packer, resulting in poor axial bidirectional damping effect. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention proposes a perforation bidirectional damper based on energy-absorbing materials and a method for evaluating its damping effect. This effectively solves the problems of poor absorption of low-frequency impact vibration waves generated during perforation and poor axial bidirectional damping effect.

[0006] This invention is achieved by adopting the following technical solution:

[0007] A perforated bidirectional shock absorber based on energy-absorbing material includes an upper connector, a central rod, a plug, a sliding shaft, a shock-absorbing spring, an upper limit gasket, a lower limit gasket, an outer sleeve, and two energy-absorbing material elements connected in series at both ends of the shock-absorbing spring. The other end of one energy-absorbing material element is abutted against the end of the upper connector via the upper limit gasket, and the other end of the other energy-absorbing material element is abutted against the end of the structure formed by the connection of the plug and the sliding shaft via the lower limit gasket.

[0008] The energy-absorbing material element has a yield strength of 300 MPa or higher, a porosity of 50% or higher, and an energy absorption density of 5 J / cm³. 3 It is made of the above-mentioned metallic materials.

[0009] The microstructure of the energy-absorbing material element includes honeycomb and porous structures.

[0010] The energy-absorbing material element has an overall ring-shaped truss structure.

[0011] The energy-absorbing material element and the shock-absorbing spring are located between the central rod and the outer sleeve.

[0012] It also includes anti-rotation keys installed in the sliding shaft and the blocked keyway.

[0013] One end of the upper connector is used to connect the drill pipe.

[0014] A method for evaluating vibration damping performance, utilizing the aforementioned bidirectional vibration damper; the evaluation method includes the following steps:

[0015] Step 1. Connect the first storage-type thermo-barometer, the bidirectional shock absorber, the second storage-type thermo-barometer, and the perforator in sequence below the drill pipe;

[0016] Step 2. The drill pipe delivers the first storage thermo-barometer, the bidirectional shock absorber, the second storage thermo-barometer, and the perforator to the predetermined position;

[0017] Step 3. Ignition and perforation: The first storage thermobarometer records the damped impact force and temperature of the tubing at the moment of perforation, and the second storage thermobarometer records the undamped impact force and temperature of the tubing at the moment of perforation.

[0018] Step 4. Read the impact force data from the first and second storage thermobarometers, compare and analyze the magnitude of the impact force, and obtain an evaluation of the shock absorption effect.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] 1. The impact vibration waves generated during perforation have the highest pressure amplitude in the low-frequency range, thus having the greatest impact on the perforation string and packer. In this bidirectional vibration damper, due to the special material properties and structure of the energy-absorbing material element, it can be applied in combined perforation testing operations. During ignition and detonation, it efficiently absorbs the low-frequency impact vibration waves generated during perforation, reducing the tensile and compressive vibrations generated by the string, preventing impact damage or breakage to the string and testing tools, and significantly improving the axial bidirectional vibration damping effect.

[0021] 2. The microstructure of the energy-absorbing material element includes honeycomb and porous structures, ensuring a porosity of over 50% and an energy absorption density of 5 J / cm³. 3 These characteristics enable it to effectively absorb low-frequency shock waves.

[0022] 3. The energy-absorbing material element has an overall ring truss structure. This structure collapses rapidly when subjected to low-frequency shock waves, effectively absorbing low-frequency vibration energy.

[0023] 4. The anti-rotation key is set in the keyway between the sliding shaft and the blockage to prevent relative rotation between the sliding shaft and the blockage.

[0024] 5. The unique structure and corresponding evaluation method of this bidirectional shock absorber enable the evaluation of its shock absorption effect. Specifically, using the evaluation method described in this invention, the impact force data collected by the first and second storage thermobarometers located on the bidirectional shock absorber are compared and analyzed. This includes data such as axial acceleration, downhole acceleration, wellbore pressure, and temperature. Since the first storage thermobarometer records the shock force and temperature experienced by the tubing at the moment of perforation after shock absorption, while the second storage thermobarometer records the undamped impact force and temperature experienced by the tubing at the moment of perforation, there are numerical differences in the axial acceleration, downhole acceleration, wellbore pressure, and temperature data collected by the two storage thermobarometers. By analyzing these data differences, the shock absorption effect of the bidirectional shock absorber can be evaluated. Attached Figure Description

[0025] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments, wherein:

[0026] Figure 1 This is a schematic diagram of the structure of the present invention;

[0027] Figure 2 This is an assembly diagram of the present invention. Figure 1 ;

[0028] Figure 3 This is an assembly diagram of the present invention. Figure 2 ;

[0029] Figure 4 This is an assembly diagram of the present invention. Figure 3 ;

[0030] Figure 5 This is a schematic diagram of the energy-absorbing material element in this invention;

[0031] Figure 6 This is a schematic cross-sectional view of AA in this invention;

[0032] Figure 7 This is a connection diagram for evaluating the vibration reduction effect in this invention;

[0033] Marked in the image:

[0034] 1. Upper connector, 2. Outer sleeve, 3. Plug, 4. Lower connector, 5. Sliding shaft, 6. Center rod, 7. Upper limit gasket, 8. Energy-absorbing material element, 9. Shock-absorbing spring, 10. Shear pin, 11. Rupture disc, 12. Anti-rotation key, 13. Drill rod, 14. First storage thermobarometer, 15. Bidirectional shock absorber, 16. Second storage thermobarometer, 17. Perforator, 19. Lower limit gasket. Detailed Implementation

[0035] Example 1

[0036] As a basic embodiment of the present invention, the present invention includes a perforated bidirectional shock absorber based on energy-absorbing material, comprising an upper connector 1, a central rod 6, a plug 3, a sliding shaft 5, a shock-absorbing spring 9, an upper limit washer 7, a lower limit washer 19, an outer sleeve 2, and two energy-absorbing material elements 8 respectively connected in series at both ends of the shock-absorbing spring 9. The other end of one energy-absorbing material element 8 rests against the end of the upper connector 1 via the upper limit washer 7, and the other end of the other energy-absorbing material element 8 rests against the end of the structure formed by the connection of the plug 3 and the sliding shaft 5 via the lower limit washer 19.

[0037] In this embodiment, the structure of the upper connector 1, center rod 6, plug 3, sliding shaft 5, shock-absorbing spring 9, upper limit gasket 7, lower limit gasket 19 and outer sleeve 2 is not improved.

[0038] Example 2

[0039] In a preferred embodiment of the present invention, the present invention includes a perforated bidirectional shock absorber based on energy-absorbing material, comprising an upper connector 1, a central rod 6, a plug 3, a sliding shaft 5, a shock-absorbing spring 9, an upper limit washer 7, a lower limit washer 19, an outer sleeve 2, and two energy-absorbing material elements 8 respectively connected in series at both ends of the shock-absorbing spring 9. The energy-absorbing material element 8 has a yield strength of 300 MPa or higher, a porosity of 50% or higher, and an energy absorption density of 5 J / cm³. 3The above-mentioned metal materials are made of honeycomb and porous microstructures. One end of one energy-absorbing material element 8 is abutted against the end of the upper connector 1 via the upper limit gasket 7, and the other end of the other energy-absorbing material element 8 is abutted against the end of the structure formed by the connection of the plug 3 and the sliding shaft 5 via the lower limit gasket 19.

[0040] Example 3

[0041] As another preferred embodiment of the present invention, please refer to the appendix to the specification. Figure 1 This invention includes a bidirectional perforation damper based on energy-absorbing material, comprising an upper connector 1, a lower connector 4, a central rod 6, a plug 3, a sliding shaft 5, a damping spring 9, an upper limit washer 7, a lower limit washer 19, an outer sleeve 2, and two energy-absorbing material elements 8. One end of the upper connector 1 is used to connect to a drill rod 13, and one end of the lower connector 4 is used to connect to a perforator 17. The plug 3 is sleeved on the outer wall of the sliding shaft 5, and a shear pin 10 is provided between the plug 3 and the sliding shaft 5. The two energy-absorbing material elements 8 are connected in series at both ends of the damping spring 9. Under the action of the upper limit washer 7, one energy-absorbing material element 8 abuts against the end of the upper connector 1, and under the action of the lower limit washer 19, the other energy-absorbing material element 8 abuts against the end of the structure formed by the connection of the plug 3 and the sliding shaft 5. The outer sleeve 2 is connected to the upper connector 1 and the plug 3 respectively, and is located between the upper connector 1 and the plug 3. The central rod 6 is located in the inner cavity formed by the connection of the upper connector 1 and the sliding shaft 5, and the outer wall of the central rod 6 is provided with two steps, one of which cooperates with the sliding shaft 5, and the other step cooperates with the upper limit gasket 7.

[0042] Refer to the instruction manual appendix Figure 5 Included with instruction manual Figure 6 The energy-absorbing material element 8 is made of a high-strength, high-porosity, and high-energy-absorbing-density metallic material. Specifically, the yield strength of the energy-absorbing material element 8 is above 300 MPa, the porosity is above 50%, and the energy absorption density is above 5 J / cm³. 3 The above-mentioned metallic materials include, but are not limited to, metals such as aluminum, calcium, and magnesium, and their alloys. The microstructure of the energy-absorbing material element 8 includes, but is not limited to, honeycomb and porous structures. The energy-absorbing material element 8 made from this material has, but is not limited to, a ring truss structure.

[0043] It also includes an anti-rotation key 12 disposed in the keyway between the sliding shaft 5 and the plug 3 to prevent relative rotation between the sliding shaft 5 and the plug 3. The outer sleeve has multiple threaded damping holes and screw holes; a rupture disc 11 is disposed in the screw hole; the rupture disc 11 has a structure that is thick at the edges and thin in the middle.

[0044] Refer to the instruction manual appendix Figure 2 ~Instruction manual included Figure 4The assembly process of the above-mentioned perforated bidirectional shock absorber 15 based on energy-absorbing material is as follows:

[0045] The first step is to install the upper limit shim 7, the lower limit shim 19, the energy-absorbing material element 8, and the shock-absorbing spring 9 into the center rod 6. The energy-absorbing material element 8 is located at both ends of the shock-absorbing spring 9, and the upper limit shim 7 and the lower limit shim 19 are located at both ends of the energy-absorbing material element 8.

[0046] The second step is to connect the center rod 6 to the sliding shaft 5.

[0047] The third step is to fix the anti-rotation key 12 in the keyway of the sliding shaft 5 and install the sliding shaft 5 into the plug 3.

[0048] The fourth step is to connect the sliding shaft 5 to the lower connector 4.

[0049] Fifth step, connect the outer sleeve 2 to the plug 3.

[0050] Step 6: Connect the upper connector 1 to the outer sleeve 2 and screw in the shear pin 10.

[0051] Step 7: Screw the broken disc 11 into the outer sleeve 2.

[0052] After assembly, the bidirectional shock absorber 15 is connected between the downhole tubing test tool and the perforator 17. The upper connector 1 connects to the test tool, and the lower connector 4 connects to the perforator 17. During the tubing run-in process until the perforating gun is ignited, the bidirectional shock absorber 15 remains rigid under the action of the shear pin 10. After ignition, the shear pin 10 is sheared by the perforation detonation wave, and the bidirectional shock absorber 15 is in a free state. At this time, under the action of the energy-absorbing material element 8, the damping spring 9, and the fluid inside the wellbore, the violent reciprocating motion of the center rod 6 and sliding shaft 5 within the upper connector 1 and plug 3 caused by the perforating gun detonation wave can be reduced, thereby achieving the effect of shock absorption for the test tool above the upper connector 1.

[0053] Specifically, when the central rod 6 and the sliding shaft 5 are subjected to upward compression by the detonation wave of the perforation gun, the sliding shaft 5 moves upward, causing the lower limit shim 19 to compress the energy-absorbing material element 8 and the shock-absorbing spring 9. The energy-absorbing material element 8 at the other end of the shock-absorbing spring 9 is fixed to the upper connector 1 under the action of the upper limit shim 7. This achieves the shock absorption effect against the compression impact.

[0054] When the central rod 6 and sliding shaft 5 are subjected to downward tension caused by the detonation wave of the perforation gun, the downward movement of the central rod 6 causes the upper limit shim 7 to compress the energy-absorbing material element 8 and the damping spring 9. The energy-absorbing material element 8 at the other end of the damping spring 9 is fixed to the plug 3 under the action of the lower limit shim 19. This achieves the damping effect against the tensile impact.

[0055] Example 4

[0056] As another preferred embodiment of the present invention, please refer to the appendix to the specification. Figure 7 This invention includes a method for evaluating vibration reduction effect, comprising the following steps:

[0057] Step 1. Connect the first storage-type thermobarometer 14, the bidirectional shock absorber 15, the second storage-type thermobarometer 16, and the perforator 17 sequentially below the drill pipe 13. The bidirectional shock absorber 15 adopts the structure described in Example 3.

[0058] Step 2. Drill rod 13 delivers the first storage thermobarometer 14, bidirectional shock absorber 15, second storage thermobarometer 16, and perforator 17 to the predetermined position.

[0059] Step 3. Ignition and perforation. The first storage thermo-barometer 14 will record the damped impact force and temperature of the tubing at the moment of perforation, while the second storage thermo-barometer 16 will record the undamped impact force and temperature of the tubing at the moment of perforation.

[0060] Step 4. Read the impact force data from the first storage thermobarometer 14 and the second storage thermobarometer 16, compare and analyze the magnitude of the impact force, and obtain an evaluation of the shock absorption effect.

[0061] In summary, any other corresponding modifications made by those skilled in the art after reading this invention document, without requiring creative mental effort, based on the technical solutions and concepts of this invention, are all within the scope of protection of this invention.

Claims

1. A perforated bidirectional shock absorber based on energy-absorbing material capable of absorbing low-frequency shock waves, comprising an upper connector (1), a central rod (6), a plug (3), a sliding shaft (5), a shock-absorbing spring (9), an upper limit washer (7), a lower limit washer (19), and an outer sleeve (2), characterized in that: It also includes two energy-absorbing material elements (8) connected in series at both ends of the damping spring (9). The other end of one energy-absorbing material element (8) is pressed against the end of the upper connector (1) via the upper limit gasket (7), and the other end of the other energy-absorbing material element (8) is pressed against the end of the structure formed by the connection of the plug (3) and the sliding shaft (5) via the lower limit gasket (19). The energy-absorbing material element (8) has a yield strength of 300 MPa or higher, a porosity of 50% or higher, and an energy absorption density of 5 J / cm³. 3 The above-mentioned metal materials are used; the energy-absorbing material element (8) has an overall ring truss structure, which collapses rapidly when subjected to low-frequency shock waves; the microstructure of the material of the energy-absorbing material element (8) includes honeycomb and pore structures; When the central rod (6) and the sliding shaft (5) are subjected to the upward compression effect generated by the detonation wave of the perforating gun, the sliding shaft (5) moves upward and drives the lower limit pad (19) to compress the energy-absorbing material element (8) and the shock-absorbing spring (9). The energy-absorbing material element (8) at the other end of the shock-absorbing spring (9) is fixed to the upper connector (1) under the action of the upper limit pad (7). When the central rod (6) and the sliding shaft (5) are subjected to the downward stretching effect generated by the detonation wave of the perforating gun, the central rod (6) moves downward and drives the upper limit pad (7) to compress the energy-absorbing material element (8) and the shock-absorbing spring (9). The energy-absorbing material element (8) at the other end of the shock-absorbing spring (9) is fixed to the plug (3) under the action of the lower limit pad (19).

2. The perforated bidirectional shock absorber based on energy-absorbing material capable of absorbing low-frequency shock waves according to claim 1, characterized in that: The energy-absorbing material element (8) and the shock-absorbing spring (9) are located between the central rod (6) and the outer sleeve (2).

3. A perforated bidirectional shock absorber based on energy-absorbing material capable of absorbing low-frequency shock waves according to claim 1, characterized in that: It also includes an anti-rotation key (12) set in the keyway between the sliding shaft (5) and the plug (3).

4. A perforated bidirectional shock absorber based on energy-absorbing material capable of absorbing low-frequency shock waves according to claim 1, characterized in that: One end of the upper connector (1) is used to connect the drill rod (13).

5. A perforated bidirectional shock absorber based on energy-absorbing material capable of absorbing low-frequency shock waves according to claim 1, characterized in that: The plug (3) is fitted onto the outer wall of the sliding shaft (5).

6. A perforated bidirectional shock absorber based on energy-absorbing material capable of absorbing low-frequency shock waves according to claim 1, characterized in that: A shear pin (10) is provided between the upper connector (1) and the center rod (6).

7. A perforated bidirectional shock absorber based on energy-absorbing material capable of absorbing low-frequency shock waves according to claim 1, characterized in that: The outer sleeve (2) is connected to the upper connector (1) and the plug (3) respectively, and is located between the upper connector (1) and the plug (3).

8. A perforated bidirectional shock absorber based on energy-absorbing material capable of absorbing low-frequency shock waves according to claim 1, characterized in that: The central rod (6) is located in the cavity formed by the connection between the upper connector (1) and the sliding shaft (5).

9. A perforated bidirectional shock absorber based on an energy-absorbing material capable of absorbing low-frequency shock waves, as described in claim 8, characterized in that: The outer wall of the central rod (6) is provided with two steps, one of which is engaged with the sliding shaft (5) and the other is engaged with the upper limit shim (7).

10. A method for evaluating vibration reduction effect, characterized in that: The evaluation method utilizes the bidirectional shock absorber (15) described in any one of claims 1 to 9; the evaluation method includes the following steps: Step 1. Connect the first storage thermo-barometer (14), the bidirectional shock absorber (15), the second storage thermo-barometer (16), and the perforator (17) in sequence below the drill rod (13). Step 2. The drill rod (13) delivers the first storage thermobarometer (14), the bidirectional shock absorber (15), the second storage thermobarometer (16), and the perforator (17) to the predetermined position; Step 3. Ignition and perforation. The first storage thermo-barometer (14) records the shock-damped impact force and temperature of the tubing at the moment of perforation, and the second storage thermo-barometer (16) records the undamped impact force and temperature of the tubing at the moment of perforation. Step 4. Read the impact force data from the first storage thermobarometer (14) and the second storage thermobarometer (16), compare and analyze the magnitude of the impact force, and obtain the evaluation of the shock absorption effect.

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