Friction damping shock absorber and working method

Abstract

The invention discloses a friction damping shock absorber and a working method. The friction damping shock absorber comprises a lower driving shaft, a bearing bracket is arranged at the shoulder of the lower driving shaft, a bearing stator is arranged above the bearing bracket, two damper assemblies are sequentially arranged above the bearing stator, and a torque screw and a spring are arranged at the connecting part between the two damper assemblies; the two sets of damper assemblies are the same in structure and opposite in direction, the upper end of the lower driving shaft penetrates into an inner hole of a damping ring in the upper damper assembly, a bearing stator and a gasket are sequentially arranged above a bearing rotor of the upper damper assembly from bottom to top, a center ring is arranged in an inner hole of the gasket, and the center ring is connected with the bearing stator. Supporting rings are arranged in inner holes of the adjusting ring, the radial bearing and the center ring of the damper assembly on the upper portion, a friction ring is arranged above the supporting rings, the friction ring is located in the inner hole of the center ring and located at the position of an inner hole step at the lower end of the connecting shaft, and the male end of the lower portion of the connecting shaft is inserted into an inner hole of the lower driving shaft.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of downhole operation tools, in particular to a frictional damping shock absorber and working method. BACKGROUND

[0002] In recent years, the continuous progress of rotary geosteering drilling technology has greatly improved the speed of oil and gas field development. The rotary steering system (RSS) plays a key role in the drilling process, which can complete the steering function in real time when the drill string is rotating, and is an important development direction of modern steering drilling technology. However, the vibration generated during drilling may have a series of effects on the rotary steering system, seriously affecting the stability of the steering instrument and the drilling efficiency. Therefore, the rotary steering dedicated shock absorbing device has a good protection for the rotary steering system, and also ensures the stability and safety of the drilling process. The integrated drilling rotary steering shock absorbing device has remarkable effects on the domestic and foreign markets.

[0003] The rotary geosteering drilling system is a core major equipment for improving the drilling efficiency of unconventional oil and gas, offshore and remaining oil in old areas, and with the gradual change of exploration and development objects to deep and ultra-deep oil and gas reservoirs, the transverse, longitudinal, stick-slip and tangential vibration are further increased, which greatly damages the rotary steering instrument and easily leads to tool failure, affecting the drilling time efficiency.

[0004] The existing shock absorber currently is to generate damping effect by mechanical (such as stacked springs) or hydraulic (such as oil cylinder) deformation, and the currently used various types of shock absorbers are mainly developed for axial vibration, lateral vibration, etc. Moreover, most of the shock absorbers are relatively long in length and can only be used at the rear end of the motor, which can solve part of the vibration from the drill string, and the current rotary steering system is commonly used, but the damping effect on the vibration from the drill bit is not obvious due to the long distance from the drill bit. Currently, there is no shock absorbing tool that can be used between the drill bit and the rotary steering system.

[0005] Therefore, there is an urgent need in the art to develop an integrated shock absorbing device for the rotary steering system, to optimize the shock absorbing structure design, to start damping from the source of the drill bit, to improve the service life of the tool, to reduce maintenance costs, and to ensure high-quality exploration and development. SUMMARY

[0006] In view of the problem of severe vibration of the drill bit and bottom hole assembly during the drilling process of deep wells, ultra-deep wells and complex structure wells, the present application provides a frictional damping shock absorber and working method.

[0007] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0008] A friction damping shock absorber, comprising a lower drive shaft, a bearing bracket is arranged at the shoulder of the lower drive shaft, a bearing stator is arranged above the bearing bracket, two groups of damper assemblies are sequentially arranged above the bearing stator, and a torque screw and a spring are arranged at the connecting part between the two groups of damper assemblies; the lower damper assembly comprises a lowermost bearing rotor, a lower step of a radial bearing penetrates into the inner hole of the bearing rotor, an upper step of the radial bearing penetrates into the inner hole of an adjusting ring, a damping ring is arranged above the adjusting ring, and the damping ring and the adjusting ring are arranged in the inner hole of a spring bracket; the two groups of damper assemblies are the same in structure and opposite in direction, the upper end of the lower drive shaft penetrates into the inner hole of the damping ring in the upper damper assembly, a bearing stator and a washer are sequentially arranged above the bearing rotor of the upper damper assembly from bottom to top, a center ring is arranged in the inner hole of the washer, a supporting ring is arranged in the inner hole of the adjusting ring, the radial bearing and the center ring of the upper damper assembly, a friction ring is arranged above the supporting ring, the friction ring is arranged in the inner hole of the center ring and at the inner hole step of the lower end of a connecting shaft, and the male end of the lower part of the connecting shaft is inserted into the inner hole of the lower drive shaft.

[0009] Further, the alloy teeth of the bearing stator at the bearing bracket face upward, and the alloy teeth of the bearing rotor face downward.

[0010] Further, the alloy teeth of the bearing stator at the supporting ring face downward, and the alloy teeth of the bearing rotor face upward.

[0011] Further, the bearing rotor, the radial bearing, the adjusting ring and the damping ring are connected together through a cylinder head screw.

[0012] Further, the bearing stator above the bearing bracket, the bearing bracket and the lower drive shaft are connected together through a cylinder head screw.

[0013] Further, the connecting shaft, the washer and the bearing stator below the washer are connected together through a cylinder head screw.

[0014] Further, one end of the torque screw is provided with a plurality of O-rings.

[0015] Further, the alloy teeth of the bearing stator and the bearing rotor are tungsten alloy sheets.

[0016] The mounting method of the friction damping shock absorber, comprising the following steps:

[0017] ① The bearing bracket is mounted into the shoulder limit from the upper end of the lower drive shaft, and the bolt holes are rotated and aligned;

[0018] ② The alloy teeth of the bearing stator face upward and are mounted from the upper end of the lower drive shaft, the bolt holes are rotated and aligned, and the cylinder head screw is mounted;

[0019] ③ Put the damping ring into the inner hole of the spring bracket, distinguish the front and back, align the screw hole, and install the torque screw;

[0020] ④ Put the adjusting ring into the inner hole of the spring bracket, and clamp it into the inner hole step of the damping ring;

[0021] ⑤ Adjust the direction of the angular contact bearing, put it into the inner hole step of the adjusting ring, and then put the bearing rotor alloy outward into the angular contact bearing; adjust the bolt hole of the above-mentioned parts in turn, and install the cylindrical head screw;

[0022] ⑥ Put the damper assembly assembled in steps ③-⑤ into the lower drive shaft with the alloy downward, and make the alloy end face of the bearing stator adhere to each other; assemble the corresponding number of springs in the spring hole on the back of the spring bracket;

[0023] ⑦ Again, according to the operation requirements of the above-mentioned steps ③-⑤, assemble another group of spring bracket, damping ring, adjusting ring, angular contact bearing, bearing rotor and cylindrical head screw in corresponding hole in turn;

[0024] ⑧ Put the damper assembly assembled in step ⑦ into the lower drive shaft with the alloy upward, and align the torque screw and spring hole; assemble two spring brackets;

[0025] ⑨ Put the support ring into the inner hole of the angular contact bearing, and align it with the upper end face of the lower drive shaft;

[0026] ⑩ Put the center ring into the lower end of the connecting shaft, put the washer into the lower end of the center ring, put the alloy teeth of the bearing stator into the center ring downward, align the bolt hole, install the cylindrical head screw, and put the friction ring into the inner hole step at the lower end of the connecting shaft;

[0027] Put the assembled assembly in steps ⑨-⑩ into the lower drive shaft, connect the connecting shaft with the lower drive shaft by screw thread, and fasten it.

[0028] The working method of the friction damping shock absorber disclosed by the application comprises the following steps:

[0029] ① When the rock drill bit drills, vibration impact is generated and transmitted to the friction damper shock absorber at the tail of the drill bit;

[0030] ② The alloy on the bearing stator and the bearing rotor of the damper rubs and slides, and converts the vibration mechanical energy into heat energy;

[0031] ③ After the shock absorber receives the impact, the elastic recovery force of the spring and the spring bracket makes the shock absorber return to the initial state;

[0032] ④ Multiple repeated actions consume energy and slow down the vibration.

[0033] Compared with the prior art, the application has the following outstanding effects:

[0034] (1) The friction damping shock absorber is a high-performance shock absorbing tool suitable for rotary steering systems, which can solve the problem of severe vibration faced by the drill bit and bottom hole assembly during drilling of deep wells, ultra-deep wells and complex structure wells, thereby protecting the rotary steering instrument, improving the rate of penetration and ensuring the quality of the wellbore.

[0035] (2) Damping characteristics: The friction damping shock absorber has good damping characteristics, which can effectively slow down the transmission and diffusion of vibration and improve the seismic performance of the structure.

[0036] (3) Stiffness characteristics: The friction damping shock absorber can have different stiffness characteristics by adjusting the stiffness of the spring and the damping force of the damper, so as to adapt to the shock absorbing needs of different structures and loads.

[0037] (4) Durability: The friction damping shock absorber uses wear-resistant, high-temperature-resistant and high-pressure-resistant friction materials and high-quality structural design to ensure its long-term stability and reliability.

[0038] (5) Frequency response characteristics: The friction damping shock absorber has good shock absorbing effect under high frequency vibration, which can effectively reduce the resonance frequency and amplitude of the structure and improve the dynamic stability of the structure.

[0039] The friction damping shock absorber and the working method thereof described in the present application will be further described below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 is a structural schematic view of the friction damping shock absorber.

[0041] Figure 2 is a structural schematic view of the bearing stator.

[0042] Figure 3 is Figure 2 view in "A-A".

[0043] Figure 4 is a structural schematic view of the bearing rotor.

[0044] Figure 5 is Figure 4 view in "B-B".

[0045] Figure 6 is a structural schematic view of the spring bracket.

[0046] Figure 7 is Figure 6 view in "C-C".

[0047] Figure 8 is Figure 6The “DD” view in the middle.

[0048] Among them, 1-connecting shaft, 2-friction ring, 3-center ring, 4-support ring, 5-washer, 6-bearing stator, 7-bearing rotor, 8-radial bearing, 9-spring bracket, 10-torque screw, 11-damping ring, 12-adjusting ring, 13-bearing bracket, 14-lower drive shaft, 15-tungsten alloy sheet, 16-cylindrical head screw, 17-spring, 18-O-ring. Detailed Implementation

[0049] like Figures 1-8 As shown (where Figure 1 (The left side represents the top, and the right side represents the bottom). A friction damping shock absorber includes a lower drive shaft 14. A bearing bracket 13 is provided at the shoulder of the lower drive shaft 14. A bearing stator 6 is provided above the bearing bracket 13. Two sets of damper assemblies are arranged sequentially above the bearing stator 6. A torque screw 10 and a spring 17 are provided at the connection between the two sets of damper assemblies. The lower damper assembly includes a bearing rotor 7 located at the bottom. The lower step of the radial bearing 8 passes through the inner hole of the bearing rotor 7. The upper step of the radial bearing 8 passes through the inner hole of the adjusting ring 12. A damping ring 11 is provided above the adjusting ring 12. The damping ring 11 and the adjusting ring 12 are located at... The inner hole of the spring bracket 9; the two sets of damper assemblies have the same structure but opposite directions. The upper end of the lower drive shaft 14 passes through the inner hole of the damping ring 11 in the upper damper assembly. The upper damper assembly has a bearing stator 6 and a washer 5 arranged from bottom to top above the bearing rotor 7. The inner hole of the washer 5 has a central ring 3. The upper damper assembly has an adjusting ring 12, a radial bearing 8, and a support ring 4 arranged in the inner hole of the central ring 3. The support ring 4 has a friction ring 2 arranged above it. The friction ring 2 is located in the inner hole of the central ring 3 and at the inner hole step of the lower end of the connecting shaft 1. The male end of the lower part of the connecting shaft 1 is inserted into the inner hole of the lower drive shaft 14.

[0050] At bearing bracket 13, the alloy teeth of bearing stator 6 face upwards, and the alloy teeth of bearing rotor 7 face downwards. At support ring 4, the alloy teeth of bearing stator 6 face downwards, and the alloy teeth of bearing rotor 7 face upwards.

[0051] The bearing rotor 7, radial bearing 8, adjusting ring 12, and damping ring 11 are connected together by head screws 16. The bearing stator 6 above the bearing bracket 13, the bearing bracket 13, and the lower drive shaft 14 are connected together by head screws 16. The connecting shaft 1, washer 5, and the bearing stator 6 below the washer 5 are connected together by head screws 16.

[0052] The torque screw 10 has multiple O-rings 18 at one end. The alloy teeth of the bearing stator 6 and bearing rotor 7 are tungsten alloy sheets 15.

[0053] The mounting method of the friction damping shock absorber comprises the following steps:

[0054] ① The bearing bracket 13 is mounted on the upper end of the lower drive shaft 14 with shoulder limiting, and the bolt holes are aligned in rotation;

[0055] ② The alloy teeth of the bearing stator 6 are mounted on the upper end of the lower drive shaft 14 with the alloy teeth facing upwards, the bolt holes are aligned in rotation, and the cylindrical head screws 16 are installed;

[0056] ③ The damping ring 11 is mounted from the inner hole of the spring bracket 9, the screw hole positions are aligned according to the front and back surfaces, and the torque screws 10 are installed;

[0057] ④ The adjusting ring 12 is mounted from the inner hole of the spring bracket 9 and clamped into the inner hole step of the damping ring 11;

[0058] ⑤ The direction of the angular contact bearing 8 is adjusted, the inner hole step of the adjusting ring 12 is mounted, and then the alloy of the bearing rotor 7 is outwardly mounted into the angular contact bearing 8; the bolt hole positions of the above-mentioned parts are adjusted in sequence, and the cylindrical head screws 16 are installed;

[0059] ⑥ The damping device assembly assembled in steps ③-⑤ is integrally mounted on the lower drive shaft 14 with the alloy facing downwards, and the alloy end surface of the bearing stator 6 is attached, and the corresponding number of springs 17 are assembled in the spring holes on the back of the spring bracket 9;

[0060] ⑦ Again, according to the operation requirements of the above-mentioned steps ③-⑤, another set of spring brackets 9, damping rings 11, adjusting rings 12, angular contact bearings 8, bearing rotors 7 and corresponding hole positions of cylindrical head screws 16 are sequentially assembled;

[0061] ⑧ The damping device assembly assembled in step ⑦ is mounted into the lower drive shaft 14 with the alloy direction facing upwards, and the hole positions of the torque screws 10 and the springs 17 are aligned to combine and assemble the two spring brackets 9;

[0062] ⑨ The support ring 4 is mounted into the inner hole of the angular contact bearing 8 and aligned with the upper end surface of the lower drive shaft 14;

[0063] ⑩ The center ring 3 is mounted from the lower end of the connecting shaft 1, the gasket 5 is mounted from the lower end of the center ring 3, then the alloy teeth of the bearing stator 6 are mounted into the center ring 3 with the alloy teeth facing downwards, the bolt hole positions are aligned, the cylindrical head screws 16 are installed, and the friction ring 2 is mounted into the inner hole step from the lower end of the connecting shaft 1;

[0064] The assembly assembled in steps ⑨-⑩ is mounted into the lower drive shaft 14, the connecting shaft 1 is threadedly connected with the lower drive shaft 14 and fastened.

[0065] The working method of the friction damping shock absorber, the specific steps are:

[0066] ①Drill bit rock breaking drilling, vibration impact is generated, and the friction damper shock absorber is transmitted to the tail of the drill bit;

[0067] ②The alloy friction sliding on the bearing stator and bearing rotor of the damper converts the vibration mechanical energy into heat energy;

[0068] ③After the shock absorber receives the impact, the elastic recovery force of the spring and the spring bracket makes the shock absorber return to the initial state;

[0069] ④Repeated action, energy consumption, and vibration reduction.

[0070] The working principle of the friction damper shock absorber is as follows:

[0071] The friction damping shock absorber is located between the drill bit and the rotary steering system. During the drilling process of the drill string, the drill bit rotates and impacts to cut and break the target rock formation, and the rotary impact load generated is directly transmitted to the friction damping shock absorber. The principle of friction damping is to reduce the acceleration and displacement of the downhole tool under the action of vibration force through the relative movement of the damper and the rotary steering tool, convert the vibration energy into heat energy and dissipate it, and reduce the drilling vibration and the response to the rotary steering tool.

[0072] The simplified model of the damper in the middle of the entire friction damping shock absorber is actually in an axial floating state. The damper is assembled and pre-tightened by the compression and reset of multiple spiral compression springs. The greater the relative displacement, the greater the damping force generated, thereby effectively reducing the vibration. When the shock absorber is subjected to external impact or vibration, the damper piston slides on the friction material, and the mechanical energy is converted into heat energy through friction, i.e. the alloy sheet inlayed between the upper and lower bearing stators 6 and the bearing rotors 7 of the shock absorber tool rubs and slides to generate heat energy, consumes energy, and reduces vibration. After the shock absorber is impacted, the spring 17 in the middle of the spring bracket 9 of the shock absorber tool plays an elastic recovery role, so that the shock absorber returns to the initial state and is ready for the next shock absorption.

[0073] The above-described embodiments are merely preferred embodiments of the present application and do not limit the scope of the present application. Without departing from the design spirit of the present application, various modifications and improvements to the technical solutions of the present application made by those skilled in the art shall fall within the protection scope determined by the claims of the present application.

Claims

1. A friction damping shock absorber, characterized in that: The system includes a lower drive shaft (14), a bearing bracket (13) at the shoulder of the lower drive shaft (14), a bearing stator (6) above the bearing bracket (13), and two sets of damper assemblies arranged sequentially above the bearing stator (6). A torque screw (10) and a spring (17) are provided at the connection between the two sets of damper assemblies. The lower damper assembly includes a bearing rotor (7) located at the bottom. The lower step of the radial bearing (8) passes through the inner hole of the bearing rotor (7), and the upper step of the radial bearing (8) passes through the inner hole of the adjusting ring (12). A damping ring (11) is provided above the adjusting ring (12), and the damping ring (11) and the adjusting ring (12) are located in the inner hole of the spring bracket (9). The damper assemblies have the same structure but opposite directions. The upper end of the lower drive shaft (14) passes through the inner hole of the damping ring (11) in the upper damper assembly. The upper damper assembly has a bearing stator (6) and a washer (5) arranged from bottom to top above the bearing rotor (7). The inner hole of the washer (5) is provided with a central ring (3). The upper damper assembly has a support ring (4) in the inner hole of the adjusting ring (12), the radial bearing (8), and the central ring (3). The support ring (4) is provided with a friction ring (2) above the support ring (4). The friction ring (2) is located in the inner hole of the central ring (3) and at the inner hole step of the lower end of the connecting shaft (1). The male end of the lower part of the connecting shaft (1) is inserted into the inner hole of the lower drive shaft (14).

2. The friction damping shock absorber according to claim 1, characterized in that: The alloy teeth of the bearing stator (6) at the bearing bracket (13) face upwards, and the alloy teeth of the bearing rotor (7) face downwards.

3. The friction damping shock absorber according to claim 2, characterized in that: The alloy teeth of the bearing stator (6) at the support ring (4) face downwards, and the alloy teeth of the bearing rotor (7) face upwards.

4. The friction damping shock absorber according to claim 3, characterized in that: The bearing rotor (7), radial bearing (8), adjusting ring (12) and damping ring (11) are connected together by cylindrical head screws (16).

5. The friction damping shock absorber according to claim 4, characterized in that: The bearing stator (6), bearing bracket (13) and lower drive shaft (14) above the bearing bracket (13) are connected together by cylindrical head screws (16).

6. The friction damping shock absorber according to claim 5, characterized in that: The connecting shaft (1), washer (5) and bearing stator (6) below washer (5) are connected together by cylindrical head screws (16).

7. The friction damping shock absorber according to claim 6, characterized in that: One end of the torque screw (10) is provided with a plurality of O-rings (18).

8. The friction damping shock absorber according to claim 7, characterized in that: The alloy teeth of the bearing stator (6) and bearing rotor (7) are tungsten alloy sheets (15).

9. The installation method of the friction damping shock absorber according to any one of claims 1-8, characterized in that, Includes the following steps: ① The bearing bracket (13) is inserted into the shoulder limiter from the upper end of the lower drive shaft (14) and rotated to align the bolt holes; ② The alloy teeth of the bearing stator (6) are inserted from the upper end of the lower drive shaft (14) with the teeth facing upward. Rotate to align the bolt holes and install the cylindrical head screws (16). ③ Insert the damping ring (11) into the inner hole of the spring bracket (9), distinguish the front and back sides and align them with the screw holes, and install the torque screw (10). ④ The adjusting ring (12) is inserted into the inner hole of the spring bracket (9) and snapped into the step of the inner hole of the damping ring (11); ⑤ Adjust the direction of the radial bearing (8), install the inner hole step of the adjusting ring (12), and then install the bearing rotor (7) with the alloy facing outward into the radial bearing (8); adjust the bolt hole positions of the above parts in sequence, and install the cylindrical head screws (16). ⑥ The damper assembly assembled in steps ③-⑤ is inserted into the lower drive shaft (14) with the alloy side down, and is fitted to the alloy end face on the bearing stator (6). The corresponding number of springs (17) are then installed in the spring holes on the back of the spring bracket (9). ⑦ Again, following the operational requirements of steps ③-⑤ above, assemble another set of spring brackets (9), damping rings (11), adjusting rings (12), radial bearings (8), bearing rotors (7), and cylindrical head screws (16) in the corresponding holes in sequence. ⑧ With the alloy direction of the damper assembly assembled in step ⑦ facing upward, insert it into the lower drive shaft (14), and at the same time align the holes of the torque screw (10) and the spring (17) to assemble the two spring brackets (9); ⑨ Insert the support ring (4) into the inner hole of the radial bearing (8) and align it with the upper end face of the lower drive shaft (14); ⑩ Insert the center ring (3) from the lower end of the connecting shaft (1), insert the washer (5) from the lower end of the center ring (3), insert the bearing stator (6) with the alloy teeth facing down into the center ring (3), align the bolt holes, install the cylindrical head screw (16), and insert the friction ring (2) from the lower end of the connecting shaft (1) into the inner hole step. Install the assembled components from steps 9-10 into the lower drive shaft (14), and thread the connecting shaft (1) to the lower drive shaft (14) and tighten it.

10. The method of operating the friction damping shock absorber according to any one of claims 1-8, characterized in that, Includes the following steps: ① When the drill bit breaks through the rock and drills, it generates vibration and impact, which is transmitted to the friction damper at the tail of the drill bit. ②The alloy friction sliding between the bearing stator and bearing rotor on the damper converts the vibration mechanical energy into heat energy; ③ After the shock absorber is impacted, the elastic restoring force of the spring and spring bracket will cause the shock absorber to return to its initial state; ④ Repeated action consumes energy and reduces vibration.

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