Vibration resistance reduction tool for well drilling

Abstract

The utility model relates to the technical field of drilling equipment, and discloses a vibration resistance reduction tool for drilling, which comprises an upper joint, a shell and a lower joint, two ends of the shell are respectively connected with the upper joint and the lower joint, a piston, an upper spring, a movable valve, a lower spring and a filter are arranged in the shell, the upper spring is sleeved at the lower end of the piston, and the lower spring is sleeved at the lower end of the filter. The other end of the upper spring abuts against the upper end face of the necking section of the shell, the lower end of the movable valve is sleeved with the lower spring, and the other end of the lower spring abuts against a positioning groove of the lower connector. The upper end face of the movable valve is provided with a central through hole and at least one outer side through hole which are both communicated with the inner cavity, the circulation area of the central through hole is smaller than the minimum circulation area of the piston, the piston abuts against the movable valve in the initial state, and the lower end face of the piston can seal all the outer side through holes of the movable valve; a first limiting structure is arranged between the piston and the shell to limit the lowest point of the piston, a second limiting structure is arranged between the movable valve and the shell to limit the lowest point of the brake valve, resonance amplification of the piston and the movable valve is achieved, and the resistance reduction effect is good.

Description

Technical Field

[0001] The utility model relates to the technical field of drilling equipment, and more specifically to a vibration drag reduction tool for drilling. Background Art

[0002] During the drilling process of extended reach wells and horizontal wells, the drill string rotates continuously, the contact area between the well wall and the drill string is large, and the friction force exerted by the well wall is too large, resulting in the drill string being unable to provide sufficient support pressure for the drill bit, ultimately leading to a very low drilling speed.

[0003] The main method to solve this problem at present is to use a hydraulic oscillator to generate axial low-frequency and low-amplitude vibration. The vibration can excite the normal vibration between the drill string and the well wall to reduce the contact area between the two and shorten the contact time between the two, thereby reducing the friction between the drill string and the well wall.

[0004] Hydraulic oscillators mainly include screw-type hydraulic oscillators and jet-type hydraulic oscillators. Screw-type hydraulic oscillators can use the rotation of drilling fluid to drive the rotor to rotate, and then the rotor drives the valve to rotate, so that the drilling fluid produces intermittent flow to form periodic pressure fluctuations and achieve axial vibration. However, the processing cost and process requirements of its rotor are high, the rubber seal has poor high temperature resistance and oil resistance, and the service life is short in oil-based mud environment. In addition, the vibration amplitude is small and the drag reduction effect is poor. It is often necessary to use it with wellbore cleaning tools, hydraulic boosters, oscillating screws, etc.

[0005] The jet hydraulic oscillator uses the jet element as the driving force, and its nozzle sprays drilling fluid into the flow channel. The special structure of the flow channel causes the drilling fluid to continuously change direction under the action of the wall, generating interception pressure pulses, and then generating axial vibration. However, it has high requirements for the solid phase of the drilling fluid. Excessive sand content will seriously erode the jet element and easily clog the jet element, causing pressure buildup. In addition, the vibration amplitude is small, and the drag reduction effect is worse than that of the spiral hydraulic oscillator. It needs to be used in conjunction with other tools.

[0006] In summary, how to develop a vibration drag reduction tool with greater drag reduction effect is an urgent problem to be solved by those skilled in the art. Utility Model Content

[0007] In view of this, the purpose of the utility model is to provide a vibration drag reduction tool for drilling, in which the piston and the movable valve can vibrate under the action of the upper and lower springs respectively, and the two can resonate to enhance the amplitude, thereby achieving good drag reduction effect and significantly improving the drilling speed of the drill string.

[0008] In order to achieve the above purpose, the present invention provides the following technical solutions:

[0009] A vibration drag reduction tool for drilling, comprising an upper joint, a housing, and a lower joint, wherein the top and bottom ends of the housing are connected to the upper joint and the lower joint respectively, and a piston, an upper spring, a movable valve, a lower spring, and a filter are arranged in the housing from top to bottom. The upper spring is sleeved on the lower end of the piston, and the other end of the upper spring abuts against the upper end surface of the necked section in the middle of the housing. The lower spring is sleeved on the lower end of the movable valve, and the other end of the lower spring abuts against the positioning groove of the lower joint through the filter.

[0010] The upper end surface of the movable valve is provided with a central through hole and at least one outer through hole, both of which are connected to the inner cavity. The flow area of ​​the central through hole is smaller than the minimum flow area of ​​the piston. In the initial state, the lower end surface of the piston abuts against the upper end surface of the movable valve, and the lower end surface of the piston can seal all the outer through holes of the movable valve.

[0011] A first limiting structure is provided between the piston and the housing, and the first limiting structure is used to limit the lowest point of the piston. A second limiting structure is provided between the movable valve and the housing, and the second limiting structure is used to limit the lowest point of the movable valve.

[0012] Preferably, the outer periphery of the piston is provided with a positioning step and a limiting step from top to bottom, the positioning step is used to abut against the upper end surface of the upper spring, and the limiting step is used to abut against the upper end surface of the necking section when the piston moves downward, so as to limit the piston axially.

[0013] Preferably, an axial distance h1 from the positioning step to the limiting step and an axial distance h2 from the limiting step to the lower end surface of the piston satisfy 5 / 6≤h1 / h2≤4 / 3.

[0014] Preferably, a plurality of spline teeth are evenly arranged on the outer periphery of the movable valve along the circumferential direction, and a connecting section for being sleeved with the lower spring is provided below the spline teeth, and the outer diameter of the connecting section is smaller than the outer diameter of the movable valve.

[0015] Preferably, the axis of the central through hole is collinear with the axis of the inner cavity of the movable valve, and the outer through holes are evenly distributed along the circumferential direction of the central through hole.

[0016] Preferably, the outer through hole is an oblique through hole, and the distance from the axis of the outer through hole to the axis of the central through hole gradually decreases from top to bottom.

[0017] Preferably, the stiffness of the lower spring is greater than that of the upper spring, and the length of the lower spring is greater than that of the upper spring.

[0018] Preferably, it further includes a bushing, which is sleeved in the outer shell, the lower end surface of the bushing abuts against the upper end surface of the lower joint, and the upper end surface of the bushing is used to abut against the movable valve so as to axially limit the lowest point of the movable valve.

[0019] Preferably, the upper joint is threadedly sleeved on the upper end of the outer shell, and at least one upper sealing ring is provided between the upper joint and the outer shell, and the upper sealing ring is clamped in the sealing groove of the upper joint.

[0020] Preferably, the lower joint is threadedly sleeved on the lower end of the shell, and at least one lower sealing ring is provided between the lower joint and the shell, and the lower sealing ring is clamped in the sealing groove of the lower joint.

[0021] After the drilling fluid flows in from the upper joint, under the action of the drilling fluid pressure, the piston and the movable valve move downward axially relative to the housing, and the upper spring and the lower spring are compressed. At this time, the lower end surface of the piston abuts against the upper end surface of the movable valve, and the lower end surface of the piston blocks and seals all the outer through holes of the movable valve;

[0022] After the piston is limited by the first limiting structure, the piston no longer moves downward, and the movable valve continues to move downward under the action of inertia and the pressure of the drilling fluid. At this time, the lower end surface of the piston is separated from the upper end surface of the movable valve, and the drilling fluid can flow downward through the central through hole and the outer through hole of the movable valve at the same time, causing the movable valve to instantly release pressure. The pressure of the drilling fluid is less than the elastic force of the lower spring. Under the action of the lower spring, the movable valve moves axially upward relative to the outer shell until the movable valve hits the lower end surface of the piston, causing the piston to vibrate up and down. At the same time, the movable valve itself will also vibrate up and down under the pressure of the drilling fluid and the elastic force of the lower spring.

[0023] Therefore, in the vibration drag reduction tool for drilling provided by the utility model, the piston and the movable valve can vibrate under the action of the upper and lower springs respectively, and the two can resonate to enhance the amplitude, so that the stress state of the drill string is transformed from static friction to dynamic friction, and drive the surrounding tools to creep together along the axial direction, thereby reducing the friction between the drill string and the well wall, achieving a good drag reduction effect and significantly improving the drilling speed of the drill string. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0025] Figure 1This is a structural schematic diagram of a specific embodiment of the vibration drag reduction tool for drilling provided by the utility model in an initial state;

[0026] Figure 2 for Figure 1 A structural diagram of a vibration drag reduction tool for drilling in a synchronous downward state;

[0027] Figure 3 for Figure 1 A schematic structural diagram of a vibration drag reduction tool for drilling in a separated state;

[0028] Figure 4 It is a cross-sectional schematic diagram in the AA direction;

[0029] Figure 5 It is a cross-sectional schematic diagram in the BB direction;

[0030] Figure 6 Schematic diagram of the structure of the upper joint;

[0031] Figure 7 Schematic diagram of the structure of the shell;

[0032] Figure 8 Schematic diagram of the structure of the piston;

[0033] Figure 9 It is the structural diagram of the movable valve;

[0034] Figure 10 It is a cross-sectional schematic diagram in CC direction;

[0035] Figure 11 Schematic diagram of the structure of the lower joint.

[0036] Figures 1-11 middle:

[0037] 1-upper joint; 2-housing; 201-neck section; 3-upper sealing ring; 4-piston; 401-positioning step; 402-limiting step; 5-upper spring; 6-moving valve; 601-central through hole; 602-outer through hole; 603-connecting section; 604-spline key teeth; 7-lower spring; 8-bushing; 9-filter disc; 901-sieve hole; 10-lower sealing ring; 11-lower joint; 1101-positioning groove. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0039] The core of the utility model is to provide a vibration drag reduction tool for drilling. The piston and the movable valve can vibrate under the action of the upper and lower springs respectively, and the two can resonate to enhance the amplitude, which has a good drag reduction effect and significantly improves the drilling speed of the drill string.

[0040] The utility model provides a vibration drag reduction tool for drilling, comprising an upper joint 1, a housing 2, and a lower joint 11. The top and bottom ends of the housing 2 are connected to the upper joint 1 and the lower joint 11, respectively. A piston 4, an upper spring 5, a movable valve 6, a lower spring 7, and a filter 9 are arranged from top to bottom in the housing 2. The upper spring 5 is sleeved on the lower end of the piston 4, and the other end of the upper spring 5 abuts against the upper end surface of the necked section 201 in the middle of the housing 2. The lower spring 7 is sleeved on the lower end of the movable valve 6, and the other end of the lower spring 7 abuts against the positioning groove 1101 of the lower joint 11 through the filter 9.

[0041] The upper end surface of the movable valve 6 is provided with a central through hole 601 and at least one outer through hole 602, both of which are connected to the inner cavity. The flow area of ​​the central through hole 601 is smaller than the minimum flow area of ​​the piston 4. In the initial state, the lower end surface of the piston 4 abuts the upper end surface of the movable valve 6, and the lower end surface of the piston 4 can seal all the outer through holes 602 of the movable valve 6.

[0042] A first limiting structure is provided between the piston 4 and the housing 2, and the first limiting structure is used to limit the lowest point of the piston 4. A second limiting structure is provided between the movable valve 6 and the housing 2, and the second limiting structure is used to limit the lowest point of the movable valve 6.

[0043] Among them, the upper joint 1 and the lower joint 11 are connected to the upper and lower drill strings respectively. Considering the convenience of processing and assembly, the upper drill string and the upper joint 1, the upper joint 1 and the shell 2, the shell 2 and the lower joint 11, and the lower joint 11 and the lower drill string are usually threaded.

[0044] Considering the overall size and sealing of the vibration drag reduction tool, please refer to Figure 1 , preferably, an upper joint 1 is threadedly sleeved on the upper end of the shell 2, and at least one upper sealing ring 3 is provided between the upper joint 1 and the shell 2, and the upper sealing ring 3 is clamped in the sealing groove of the upper joint 1;

[0045] The lower joint 11 is threadedly sleeved on the lower end of the housing 2 , and at least one lower sealing ring 10 is provided between the lower joint 11 and the housing 2 . The lower sealing ring 10 is clamped in the sealing groove of the lower joint 11 .

[0046] The upper spring 5 and the lower spring 7 can cooperate with the drilling fluid pressure to drive the piston 4 and the movable valve 6 respectively to form reciprocating vibration. Considering that the lower spring 7 can drive the movable valve 6 to move upward and hit the piston 4, the maximum elastic force of the lower spring 7 must be greater than the maximum elastic force of the upper spring 5.

[0047] The specific materials, structures and dimensions of the upper spring 5 and the lower spring 7 are determined according to actual production needs. Taking into account the actual vibration process of the vibration drag reduction tool, the stiffness of the lower spring 7 is usually set to be greater than the stiffness of the upper spring 5, and the length of the lower spring 7 is greater than the length of the upper spring 5, so that the lower spring 7 can drive the movable valve 6 to hit the piston 4 upward, causing the piston 4 to vibrate up and down.

[0048] The first limiting structure includes the upper end surface of the necking section 201 in the middle of the shell 2 and a common axial limiting structure such as a limiting step 402 or a retaining spring of the piston 4. When the axial limiting structure of the piston 4 abuts against the upper end surface of the necking section 201, the piston 4 cannot continue to move axially downward due to the upper end surface of the necking section 201, thereby achieving axial limiting of the lowest point of the piston 4.

[0049] The second limiting structure includes a positioning step of the movable valve 6 for abutting against the lower spring 7 and common axial limiting structures such as a retaining spring, a limiting step or a bushing 8 in the outer shell 2. When the positioning step of the movable valve 6 abuts against the axial limiting structure of the outer shell 2, the movable valve 6 cannot continue to move axially downward due to the axial limiting structure, thereby achieving axial limiting of the movable valve 6.

[0050] In the initial state, the upper end surface of the piston 4 abuts against the lower end surface of the upper joint 1, and the lower end surface of the piston 4 abuts against the upper end surface of the movable valve 6. The lower end surface of the piston 4 blocks and seals all the outer through holes 602 of the movable valve 6. Figure 1 As shown, the inner cavity of the upper joint 1, the inner cavity of the piston 4, and the inner cavity of the movable valve 6 are connected to the inner cavity of the lower joint 11 through the sieve hole 901 of the filter plate 9, so that the drilling fluid can flow smoothly in the vibration drag reduction tool.

[0051] After the drilling fluid flows in from the upper joint 1, under the pressure of the drilling fluid, the piston 4 and the movable valve 6 move downward relative to the housing 2 along the axial direction. Figure 2 As shown, the upper spring 5 and the lower spring 7 are both compressed. At this time, the lower end surface of the piston 4 abuts against the upper end surface of the movable valve 6. The lower end surface of the piston 4 blocks and seals all the outer through holes 602 of the movable valve 6.

[0052] After the piston 4 is limited by the first limiting structure, the piston 4 no longer moves downward, and the movable valve 6 continues to move downward under the action of inertia and the pressure of the drilling fluid. At this time, the lower end surface of the piston 4 is separated from the upper end surface of the movable valve 6. Figure 3As shown, drilling fluid can simultaneously flow downward through the central through-hole 601 and the outer through-hole 602 of the movable valve 6, causing the movable valve 6 to instantly release pressure. The drilling fluid pressure is less than the elastic force of the lower spring 7. Under the action of the lower spring 7, the movable valve 6 moves axially upward relative to the housing 2 until the movable valve 6 strikes the lower end surface of the piston 4, causing the piston 4 to vibrate up and down. Simultaneously, the movable valve 6 itself also vibrates up and down under the action of the drilling fluid pressure and the elastic force of the lower spring 7. Under the action of the drilling fluid, this process repeats continuously, and the piston 4 and the movable valve 6 can form a resonance to enhance the amplitude.

[0053] In this embodiment, the piston 4 and the movable valve 6 can vibrate under the action of the upper and lower springs respectively, and the two can resonate to enhance the amplitude, so that the stress state of the drill string is transformed from static friction to dynamic friction, and drive the surrounding tools to creep together along the axial direction, thereby reducing the friction between the drill string and the well wall, achieving a good drag reduction effect and significantly improving the drilling speed of the drill string.

[0054] On the basis of the above embodiment, the structure of the piston 4 is defined, and a positioning step 401 and a limiting step 402 are provided on the outer periphery of the piston 4 from top to bottom. The positioning step 401 is used to abut against the upper end surface of the upper spring 5, and the limiting step 402 is used to abut against the upper end surface of the necking section 201 when the piston 4 moves downward, so as to limit the piston 4 axially.

[0055] Please refer to Figure 1 In the initial state, one end of the upper spring 5 abuts against the positioning step 401, and the other end abuts against the upper end surface of the necked section 201 in the middle of the housing 2. The axial distance from the positioning step 401 to the upper end surface of the necked section 201 determines the length of the upper spring 5.

[0056] The limiting step 402 is provided between the positioning step 401 and the lower end surface. The axial distance h1 from the positioning step 401 to the limiting step 402 determines the stroke of the piston 4 and also determines the actual maximum compression amount of the upper spring 5 .

[0057] Considering the vibration frequency requirement of the piston 4 , the axial distance h1 from the positioning step 401 to the limiting step 402 and the axial distance h2 from the limiting step 402 to the lower end face of the piston 4 are usually set to meet the following conditions: 5 / 6≤h1 / h2≤4 / 3.

[0058] In this embodiment, the positioning step 401 is used to abut against the upper end of the upper spring 5, and the limiting step 402 is used to cooperate with the upper end surface of the middle necked section 201 of the shell 2 to perform axial limiting of the lowest point. The structure is simple, easy to process, and convenient to assemble.

[0059] On the basis of the above embodiment, the structure of the movable valve 6 is defined. The outer periphery of the movable valve 6 is evenly provided with a number of spline teeth 604 along the circumferential direction. The specific number, structure, shape and size of the spline teeth 604 are determined according to actual production needs and are not repeated here. A connecting section 603 for being sleeved with the lower spring 7 is provided below the spline teeth 604. The outer diameter of the connecting section 603 is smaller than the outer diameter of the movable valve 6, so that a positioning step is formed between the connecting section 603 and the connecting end face of the movable valve body, and the positioning step is used to perform axial positioning of the lower spring 7.

[0060] The upper end surface of the movable valve 6 is provided with a central through hole 601 and at least one outer through hole 602. The central through hole 601 and the outer through hole 602 are both connected to the inner cavity of the movable valve 6 so that the drilling fluid can flow downward through the movable valve 6. The specific shapes and sizes of the two are not limited, but it is necessary to ensure that the flow area of ​​the central through hole 601 is smaller than the minimum flow area of ​​the piston 4, so as to increase the drilling fluid pressure on the movable valve 6 in the downward state by reducing the flow channel area.

[0061] By adjusting the flow area of ​​the central through hole 601 and the ratio of the total flow area of ​​the central through hole 601 and the outer through hole 602, the pressure release speed after the movable valve 6 is separated from the piston 4 can be adjusted, and the drilling hydraulic pressure difference before and after the pressure release can be effectively adjusted.

[0062] In order to facilitate the processing of the movable valve 6, it is preferred to set the axis of the central through hole 601 to be collinear with the axis of the inner cavity of the movable valve 6, and the outer through holes 602 are evenly distributed along the circumferential direction of the central through hole 601;

[0063] At the same time, in order to avoid the axis of the outer through hole 602 being too close to the axis of the central through hole 601, which will cause the inner diameter of the piston 4 to be reduced, affect the flow area of ​​the piston 4, and cause the outer through hole 602 to be eroded and connected with the central through hole 601 after long-term operation, it is preferred to set the outer through hole 602 as an oblique through hole, and the distance from the axis of the outer through hole 602 to the axis of the central through hole 601 gradually decreases from top to bottom.

[0064] On the basis of the above embodiment, in order to facilitate the axial limitation of the movable valve 6, a bushing 8 can also be provided. The bushing 8 is sleeved in the outer shell 2, and the lower end surface of the bushing 8 abuts against the upper end surface of the lower joint 11. The upper end surface of the bushing 8 is used to abut against the movable valve 6 so as to axially limit the lowest point of the movable valve 6.

[0065] On the premise that the sizes of the movable valve 6 and the lower spring 7 are certain, replacing the bushing 8 with different lengths can adjust the lowest point of the up and down vibration of the movable valve 6, and then adjust the vibration frequency of the movable valve 6; the specific material, structure and size of the bushing 8 are based on actual production needs and will not be repeated here.

[0066] In this embodiment, the sleeve 8 is used to limit the stroke of the movable valve 6. Compared with processing a limit step or a retaining ring groove on the inner surface of the outer shell 2, it not only simplifies the processing of the outer shell 2, but also facilitates the assembly of the vibration drag reduction tool. It can also adjust the vibration frequency of the movable valve 6 by replacing the sleeve 8 of different lengths, thereby improving the applicability of the vibration drag reduction tool.

[0067] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0068] The above describes in detail the vibration drag reduction tool for drilling provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above examples is intended only to facilitate understanding of the method and core concept of the present invention. It should be noted that those skilled in the art may make various improvements and modifications to the present invention without departing from the principles of the present invention, and such improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A vibration drag reduction tool for drilling, characterized in that: It comprises an upper joint (1), a shell (2) and a lower joint (11), wherein the top and bottom ends of the shell (2) are connected to the upper joint (1) and the lower joint (11) respectively, and a piston (4), an upper spring (5), a movable valve (6), a lower spring (7) and a filter (9) are provided in the shell (2) from top to bottom, wherein the upper spring (5) is sleeved on the lower end of the piston (4), and the other end of the upper spring (5) abuts against the upper end surface of the necking section (201) in the middle of the shell (2), and the lower spring (7) is sleeved on the lower end of the movable valve (6), and the other end of the lower spring (7) abuts against the positioning groove (1101) of the lower joint (11) through the filter (9); The upper end surface of the movable valve (6) is provided with a central through hole (601) and at least one outer through hole (602) both of which are in communication with the inner cavity. The flow area of ​​the central through hole (601) is smaller than the minimum flow area of ​​the piston (4). In the initial state, the lower end surface of the piston (4) abuts against the upper end surface of the movable valve (6). The lower end surface of the piston (4) can seal all the outer through holes (602) of the movable valve (6). A first limiting structure is provided between the piston (4) and the housing (2), the first limiting structure being used to limit the lowest point of the piston (4), and a second limiting structure is provided between the movable valve (6) and the housing (2), the second limiting structure being used to limit the lowest point of the movable valve (6).

2. The vibration drag reduction tool for drilling according to claim 1, characterized in that: The outer periphery of the piston (4) is provided with a positioning step (401) and a limiting step (402) from top to bottom. The positioning step (401) is used to abut against the upper end surface of the upper spring (5), and the limiting step (402) is used to abut against the upper end surface of the necking section (201) when the piston (4) moves downward, so as to axially limit the piston (4).

3. The vibration drag reduction tool for drilling according to claim 2, characterized in that: The axial distance h1 from the positioning step (401) to the limiting step (402) and the axial distance h2 from the limiting step (402) to the lower end surface of the piston (4) satisfy the following relationship: 5 / 6≤h1 / h2≤4 / 3.

4. The vibration drag reduction tool for drilling according to claim 1, characterized in that: The outer periphery of the movable valve (6) is evenly provided with a plurality of spline teeth (604) along the circumferential direction. A connecting section (603) for sleeve connection with the lower spring (7) is provided below the spline teeth (604). The outer diameter of the connecting section (603) is smaller than the outer diameter of the movable valve (6).

5. The vibration drag reduction tool for drilling according to claim 1, characterized in that: The axis of the central through hole (601) is collinear with the axis of the inner cavity of the movable valve (6), and the outer through holes (602) are evenly distributed along the circumferential direction of the central through hole (601).

6. The vibration drag reduction tool for drilling according to claim 5, characterized in that: The outer through hole (602) is an oblique through hole, and the distance between the axis of the outer through hole (602) and the axis of the central through hole (601) gradually decreases from top to bottom.

7. The vibration drag reduction tool for drilling according to any one of claims 1 to 6, characterized in that: The stiffness of the lower spring (7) is greater than the stiffness of the upper spring (5), and the length of the lower spring (7) is greater than the length of the upper spring (5).

8. The vibration drag reduction tool for drilling according to any one of claims 1 to 6, characterized in that: It also includes a bushing (8), which is sleeved in the housing (2), the lower end surface of the bushing (8) abuts against the upper end surface of the lower joint (11), and the upper end surface of the bushing (8) is used to abut against the movable valve (6) so as to axially limit the lowest point of the movable valve (6).

9. The vibration drag reduction tool for drilling according to any one of claims 1 to 6, characterized in that: The upper joint (1) is threadedly sleeved on the upper end of the outer shell (2), and at least one upper sealing ring (3) is provided between the upper joint (1) and the outer shell (2), and the upper sealing ring (3) is clamped in the sealing groove of the upper joint (1).

10. The vibration drag reduction tool for drilling according to any one of claims 1 to 6, characterized in that: The lower joint (11) is threadedly sleeved on the lower end of the outer shell (2), and at least one lower sealing ring (10) is provided between the lower joint (11) and the outer shell (2), and the lower sealing ring (10) is clamped in the sealing groove of the lower joint (11).

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