CN117627624A - Vibration damper for measurement while drilling instrument and vibration damping method - Google Patents

Abstract

The invention provides a vibration damper for a measurement while drilling instrument and a vibration damping method, wherein the vibration damper comprises the following components: the outer diameter of the lower end of the upper joint is reduced to form a first connecting part; the damping cylinder is fixedly sleeved on the first connecting part, and the inner diameter of the lower end of the damping cylinder is reduced to form a stop part; the outer diameter of the upper end of the lower joint is reduced to form a second connecting part; the spacer bush is fixedly sleeved on the second connecting part; the shock absorber comprises a shock absorber tube, a shock absorber sleeve, a shock absorber, a first connecting part, a second connecting part, a first elastic part, a second elastic part, a first connecting part, a second elastic part and a third connecting part, wherein the shock absorber tube is sleeved with the shock absorber sleeve in a sliding mode. The invention can be arranged between the compression-resistant cylinders of each module of the measurement while drilling instrument, and is directly used for vibration reduction between the compression-resistant cylinders, thereby indirectly reducing vibration and impact of an electronic circuit in the instrument. The existing underground measurement while drilling instrument does not need to be modified, and the installation is convenient. The shock absorber can be directly replaced after being damaged, and has good interchangeability.

Description

Vibration damper for measurement while drilling instrument and vibration damping method

Technical Field

The invention belongs to the technical field of petroleum and natural gas downhole instruments, and particularly relates to a vibration damper for a measurement while drilling instrument and a vibration damping method for the measurement while drilling instrument.

Background

The main functions of the measurement while drilling instrument include measuring well inclination angle, azimuth angle, tool face angle and auxiliary parameters such as temperature, pressure and the like, and transmitting measured data to a ground system in a wireless transmission mode in time. The ground system processes the physical information into corresponding physical information through corresponding algorithms to guide real-time drilling operation and later oil gas development.

The measurement while drilling instrument is affected by vibration, erosion and the like in the drilling process, and the working environment is very bad. Related drilling data show that the vibration magnitude of the measurement while drilling instrument is between 15g and 20g, and the instantaneous impact can reach 50g or even larger magnitude.

The measurement while drilling instrument comprises a plurality of circuit modules and compression-resistant cylinders arranged outside the circuit modules, wherein the compression-resistant cylinders are mutually connected in series. At present, the connection mode between the circuit module and the compression-resistant cylinder and between the compression-resistant cylinder and the adjacent parts is rigid connection, and the connection mode has the advantages of simple structure and convenient connection. However, if the device is in a well condition environment with strong vibration, the device is extremely easy to be influenced by vibration and impact of a drill string, so that the data of the measuring device are inaccurate, even the device is damaged, and the measuring reliability of the device is reduced.

Currently, there are several shock absorbing devices for downhole tools, but there are a number of drawbacks.

The 1 st is a vibration damping nipple. The vibration damping nipple is directly connected to a drill string and a drill collar in a well to reduce instrument vibration connected to the drill string or suspended in a water hole of the drill string. This approach is most directly effective, directly blocking or damping the vibration of the drill string. However, in this arrangement, since the damping nipple is a weak point of the whole drilling tool assembly, the damping nipple is arranged to reduce the overall strength of the drilling tool assembly, and may cause downhole accidents such as drill fracture, and thus the risk is high.

The 2 nd is to mount the damper on the circuit frame inside the downhole instrument. For example, patent document US6916248B1 discloses a damper for a downhole tool, which is composed of an outer housing, an inner shaft, a damping rubber body, and the like. The shock absorber is positioned inside a compression-resistant cylinder of the instrument, is connected between the short joint of the centralizer and the circuit framework of the instrument, and is directly used for reducing vibration and impact of electronic devices inside the circuit framework. However, the arrangement needs to arrange a shock absorber between each circuit module and the compression-resistant cylinder, and has complex structure and poor use effect. In addition, the vibration reduction scheme can improve the vibration condition of a circuit board internally mounted on a circuit framework of the downhole instrument, but has no vibration reduction effect on the downhole instrument string. Although the circuit board within the instrument is protected, there is no improvement in vibration of the instrument string. Thus, problems such as instrument string tripping, seal failure, etc. may occur.

Disclosure of Invention

Aiming at the technical problems, the invention aims to provide a shock absorber for a measurement while drilling instrument, which can be directly used on a compression-resistant cylinder of the measurement while drilling instrument, has good interchangeability and can play a role in sufficient shock absorption.

The invention also provides a vibration reduction method of the measurement while drilling instrument, which can play a role in vibration reduction of the measurement while drilling instrument.

According to the present invention, there is provided a shock absorber for a measurement while drilling apparatus, comprising: the outer diameter of the lower end of the upper joint is reduced to form a first connecting part; the damping cylinder is fixedly sleeved on the first connecting part, and the inner diameter of the lower end of the damping cylinder is reduced to form a stop part; the outer diameter of the upper end of the lower joint is reduced to form a second connecting part; the spacer bush is fixedly sleeved on the second connecting part; the shock absorber comprises a shock absorber tube, a shock absorber sleeve, a shock absorber, a spacer sleeve, a first connecting part, a second connecting part and a second connecting part, wherein the spacer sleeve is slidably sleeved in the shock absorber tube, a first elastic part is arranged between the spacer sleeve and the first connecting part, and a second elastic part is arranged between the spacer sleeve and the stop part.

In one embodiment, the first elastic member and the second elastic member are disc springs.

In one embodiment, the number of the disc springs is a plurality, and the disc springs are mutually matched or overlapped.

In one embodiment, an elastic ring is sleeved on the second connecting portion, and the elastic ring is respectively abutted with the vibration reduction cylinder and the lower joint.

In one embodiment, an anti-rotation hole is arranged in the stop part, and an anti-rotation body matched with the anti-rotation hole is arranged on the second connecting part.

In one embodiment, the anti-rotation holes and the anti-rotation body are regular hexagons in cross section.

In one embodiment, the first connecting portion is provided with a first external thread, the vibration reduction cylinder is internally provided with a first internal thread matched with the first external thread, the second connecting portion is provided with a second external thread, and the spacer bush is internally provided with a second internal thread matched with the second external thread.

In one embodiment, seals are provided between the damper cylinder and the first connection, between the spacer and the second connection, and between the spacer and the damper cylinder.

In one embodiment, a wire receiving channel is provided in the interior of the shock absorber in the direction of its central axis.

According to the invention, a vibration reduction method of the measurement while drilling instrument is also provided, and the vibration reduction device is directly arranged on the body of the measurement while drilling instrument.

Compared with the prior art, the application has the advantages that:

the shock absorber for the measurement while drilling instrument is arranged among the compression resistant cylinders of each module of the measurement while drilling instrument through threads, is directly used for vibration reduction among the compression resistant cylinders, and indirectly reduces vibration and impact of an electronic circuit inside the instrument. Therefore, the existing underground measurement while drilling instrument does not need to be modified, and the installation is convenient. In addition, the shock absorber can be directly replaced after being damaged, and has good interchangeability.

Drawings

The present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a schematic view of a shock absorber for a measurement while drilling tool according to the present invention;

fig. 2 shows a schematic view of an upper joint according to the invention;

FIG. 3 shows a schematic view of a damper cylinder according to the present invention;

fig. 4 shows a schematic cross-section of a stop according to the invention;

fig. 5 shows a schematic view of a lower joint according to the invention;

FIG. 6 is a schematic cross-sectional view of A-A of FIG. 5;

FIG. 7 is a schematic cross-sectional view of B-B of FIG. 5;

FIG. 8 shows a schematic view of a spacer according to the present invention;

FIG. 9 shows a schematic view of an elastic member according to the present invention;

fig. 10 shows a schematic view of an elastic ring according to the invention.

In this application, all of the figures are schematic drawings which are intended to illustrate the principles of the invention and are not to scale.

Detailed Description

The invention is described below with reference to the accompanying drawings.

In this application, it should be noted that the direction approaching the lower joint 3 according to the present invention is described as "lower end" or the like, and the direction approaching the upper joint 1 according to the present invention is described as "upper end" or the like.

Fig. 1 shows a structure of a shock absorber 100 according to the present invention. As shown in fig. 1, the shock absorber 100 includes an upper joint 1, a shock absorbing cylinder 2, a lower joint 3, a spacer 4, a first elastic member 5, a second elastic member 6, and an elastic ring 7. In the embodiment, the vibration reduction cylinder 2 is coaxially and fixedly sleeved on the outer side of the lower part of the upper joint 1. The spacer bush 4 is coaxially fixed and sleeved on the outer side of the upper part of the lower joint 3. The spacer 4 is slidably disposed inside the damper cylinder 2. The first elastic member 5 and the second elastic member 6 are coaxially disposed within the damper cylinder 2. The first elastic piece 5 is arranged between the spacer bush 4 and the upper joint 1, the upper end of the first elastic piece 5 is abutted with the upper joint 1, and the lower end of the first elastic piece 5 is abutted with the spacer bush 4. The second elastic member 6 is provided between the spacer 4 and the lower end of the damper cylinder 2. In a specific embodiment, as shown in fig. 3, the lower part of the damper cylinder 2 is provided with a stopper 26. The second elastic member 6 is provided between the spacer 4 and the stopper 26. With this arrangement, the upper joint and the lower joint can be relatively displaced in the axial direction, and the first elastic member 5 and the second elastic member 6 can play a role in buffering and damping the relative displacement between the upper joint 1 and the lower joint 3. That is, when the lower joint 3 moves upward with respect to the upper joint 1, the first elastic member 5 is compressed by the spacer 4; when the lower joint 3 moves downwards relative to the upper joint 1, the second elastic piece 6 is compressed by the spacer bush 4, so that the complex working condition under the well is adapted. Meanwhile, the spacer bush 4 is arranged in the vibration reduction cylinder 2 in a sliding mode, and can also play a role in guiding.

The invention directly installs the shock absorber 100 on the body of the downhole instrument string (i.e. the measurement while drilling instrument), namely the shock absorber 100 can be directly connected with the self-contained compression-resistant cylinder of the downhole instrument (i.e. the measurement while drilling instrument, not shown in the figure) through the upper joint 1 and the lower joint 3. Shock absorber 100 may provide a shock absorbing effect on the entire tool string. Therefore, the probability of occurrence of problems such as instrument string tripping and sealing failure is greatly reduced, and vibration of a circuit board in the instrument can be reduced, so that the effect of protecting a circuit is achieved. Meanwhile, the invention has high structural strength, and does not have the risk of weakening the strength of the underground drill string like a vibration damping pup joint in the prior art.

According to the invention, a wire receiving channel 8 is provided in the interior of the shock absorber 100 in the direction of its central axis. With this arrangement, the lead wires of the measurement while drilling instrument can be passed through the shock absorber 100 for easy installation.

In a specific embodiment, as shown in fig. 2, the upper joint 1 includes an upper body 12 and a first connecting portion 15. The first connecting portion 15 is used for connecting with the vibration damping cylinder 2, wherein the outer diameter of the first connecting portion 15 is smaller than the outer diameter of the upper body 12, and the outer diameter of the vibration damping cylinder 2 is equal to the outer diameter of the upper body 12. With this arrangement, the overall outer diameter of shock absorber 100 is equalized, facilitating downhole operations.

In a specific embodiment, as shown in fig. 2 and 3, a first seal and a first external thread 14 are provided on the first connection 15. Meanwhile, the main body 24 of the damper cylinder 2 has a cylindrical tubular shape, and the first sealing surface 21 and the first female screw 22 are provided inside the main body 24. Wherein the first sealing surface 21 forms a sealing structure with the first seal and the first external thread 14 and the first internal thread 22 form a threaded connection. By providing threads, the damper cylinder 2 and the upper joint 1 can be quickly disassembled. By arranging the sealing element, the sealing effect is enhanced.

In a preferred embodiment, the first seal comprises a first seal groove 13 and a first seal ring (not shown) disposed within the first seal groove 13.

In a specific embodiment, as shown in fig. 3 and 8, a second sealing surface 23 and a stop 26 are also provided on the inside of the body 24. Meanwhile, a third sealing surface 41 and a second sealing groove 42 are provided on the outer side of the spacer 4. A second seal ring 45 is provided in the second seal groove 42. By this arrangement, after the spacer 4 is slidably fitted inside the damper cylinder 2, a seal structure can be formed between the third seal surface 41 and the second seal surface 23, preventing external contaminants from entering the inside of the damper 100.

In a specific embodiment, the upper end and the lower end of the spacer 4 are respectively abutted with a first elastic member 5 and a second elastic member 6. The upper end of the first elastic piece 5 is abutted with the upper joint 1, and the lower end is abutted with the spacer bush 4. The upper end of the second elastic member 6 abuts against the spacer 4, and the lower end abuts against the stopper 26. The first elastic member 5 and the first elastic member 6 are similar in structure, taking the first elastic member 5 as an example. As shown in fig. 9, the first elastic member 5 includes a plurality of disc springs 51. The disc springs 51 may be arranged in a pairwise opposite manner in fig. 5, or may be arranged in a stacked manner with the same direction. By the arrangement, the characteristics of short reaction time and high response speed of the disc spring 51 are fully utilized, and the high-frequency vibration caused by the drilling tool can be well damped.

In a particular embodiment, as shown in fig. 5 and 8, the inside of the spacer 4 is provided with a fourth sealing surface 43 and a second internal thread 44. The lower joint 3 includes a lower body 36 and a second connecting portion 30. Wherein a third sealing groove 32 and a second external thread 33 are provided on the second connection. A third seal ring 31 is provided in the third seal groove 32. In the present embodiment, the number of the third seal grooves 32 is two, and the third seal ring 31 is provided in each of the third seal grooves. With this arrangement, the spacer bush 4 and the lower joint 3 are fixedly connected by the second external thread 33 and the second internal thread 44, and the third seal ring 31 and the fourth seal ring 43 form a seal structure. The disassembly is convenient, and the external dirt is effectively prevented from entering the inside of the shock absorber 100.

In a specific embodiment, the second connecting portion 30 is further provided with an anti-rotation body 34. As shown in fig. 3 to 7, an anti-rotation hole 261 is provided in the stopper 26 along the axial direction, and the anti-rotation hole 261 matches the anti-rotation body 34, and the anti-rotation hole 261 matches the cross-sectional shape of the anti-rotation body 34. The cross-sectional shape of the anti-rotation body 34 is polygonal as long as the anti-rotation body 34 is prevented from rotating in the anti-rotation hole 261. After the lower joint 3 enters the damper cylinder 2, the stopper 26 provided with the rotation preventing hole 261 can generate relative displacement within the length range of the rotation preventing body 34. With this arrangement, the lower joint 3 can be restrained from rotating relative to the damper cylinder 2, so that the lower joint 3 can move only in the axial direction relative to the damper cylinder 2.

In a preferred embodiment, the anti-rotation body 34 has a regular hexagonal cross-sectional shape. The regular hexagon is simple to process compared with other polygonal shapes, and has large bearing capacity.

In a particular embodiment, the outer diameter of the second connecting portion 30 is smaller than the outer diameter of the lower body 36, thereby forming a shoulder 35 at the junction of the lower body 36 and the second connecting portion 30. Referring to fig. 1, the elastic ring 7 is sleeved on the second connecting portion 30. The upper end of the elastic ring 7 abuts against the stopper 26 of the damper cylinder 2, and the lower end abuts against the shoulder 35. With this arrangement, the elastic ring 7 can further play a role of cushioning.

According to the invention, the shape of the inner ring of the elastic ring 7 corresponds to the shape of the anti-rotation body 34. As shown in fig. 10, in the present embodiment, the inner ring of the elastic ring 7 is a regular hexagon.

According to the embodiment of the invention, the disassembly and assembly are convenient, and the installation process is as follows.

S1, the elastic ring 7 is sleeved on the shoulder 35 of the lower joint 3. The damper cylinder 2 is placed in the upper end of the lower joint 3, taking care of the cooperation of the anti-rotation hole 261 and the anti-rotation body 34. The bottom of the vibration reduction cylinder 2 is attached to the elastic ring 7. The second elastic member 6 is placed in the annular space formed by the damper cylinder 2 and the lower joint 3, so that the second elastic member 6 is sleeved on the lower joint 3, and the bottom of the second elastic member 6 is in contact with the stop portion 26 of the damper cylinder 2. The spacer bush 4 is connected with the lower joint 3 through threads. The first elastic member 5 is placed in the damper cylinder 2 so that the bottom of the first elastic member 5 is in contact with the spacer 4. S2, connecting the upper joint 1 with the vibration reduction cylinder 2 through threads.

In one embodiment of the present invention, a method of damping vibration of a measurement while drilling instrument is provided using a vibration damper 100 provided in accordance with the present invention. The present example is described in terms of a method of damping vibration in a MWD instrument, as follows.

The lead wire of the MWD passes through the upper joint 1 through a wire containing channel 8, the upper joint 1 is connected with a compression-resistant cylinder of the MWD instrument in a threaded connection mode, and sealing treatment is carried out. The installation is performed according to the above-described installation procedure S1. The MWD leads are passed through the wire receiving passage 8 through the partial damper assembled according to step S1. The MWD leads are connected to another instrument that needs to be connected below. The upper joint 1 is connected with the vibration reduction cylinder 2 through threads. The compression-resistant cylinder of the other instrument is connected with the lower joint 3 through threads.

It is easy to understand that the invention is used for vibration reduction of various underground instruments, and the invention is arranged between the compression-resistant cylinders of the underground instruments, can reduce vibration and impact of the underground instruments in the drilling process, improves the measuring accuracy of the instruments and prolongs the service life. The invention can be directly arranged between the compression-resistant cylinders of the existing underground instruments, does not need to independently implement shock absorption measures for each underground instrument, and is convenient to use.

In the description of the present invention, it should be understood that the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present invention, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Finally, it should be noted that the above description is only of a preferred embodiment of the invention and is not to be construed as limiting the invention in any way. Although the invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the techniques described in the foregoing examples, or equivalents may be substituted for elements thereof. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A shock absorber for a measurement while drilling instrument, comprising:

an upper joint (1), wherein the outer diameter of the lower end of the upper joint (1) is reduced to form a first connecting part (15);

the damping cylinder (2) is fixedly sleeved on the first connecting part (15), and the inner diameter of the lower end of the damping cylinder (2) is reduced to form a stop part (26);

a lower joint (3), wherein the outer diameter of the upper end of the lower joint (3) is reduced to form a second connecting part (30);

a spacer bush (4) fixedly sleeved on the second connecting part (30);

the shock absorber comprises a shock absorber tube (2), a spacer bush (4) and a first elastic piece (5) arranged between the spacer bush (4) and a first connecting portion (15), and a second elastic piece (6) arranged between the spacer bush (4) and a stop portion (26).

2. The shock absorber according to claim 1, wherein the first elastic member (5) and the second elastic member (6) are disc springs.

3. The shock absorber of claim 2 wherein said plurality of disc springs are stacked or intermeshed with each other.

4. A shock absorber according to claim 3, wherein an elastic ring (7) is provided over the second connection portion (30), the elastic ring (7) being in abutment with the shock absorber tube (2) and the lower joint (3), respectively.

5. The shock absorber according to claim 4, characterized in that an anti-rotation hole (261) is provided in the stop portion (26), and an anti-rotation body (34) cooperating with the anti-rotation hole (261) is provided on the second connection portion (30).

6. The shock absorber according to claim 5, wherein the anti-rotation holes (261) and the anti-rotation bodies (34) have regular hexagonal cross sections.

7. The shock absorber according to claim 6, wherein a first external thread is provided on the first connecting portion (15), a first internal thread is provided in the shock absorbing cylinder (2) and is engaged with the first external thread, a second external thread is provided on the second connecting portion (30), and a second internal thread is provided in the spacer (4) and is engaged with the second external thread.

8. The shock absorber according to claim 7, wherein seals are provided between the shock tube (2) and the first connection (15), between the spacer (4) and the second connection (30) and between the spacer (4) and the shock tube (2).

9. A shock absorber according to claim 8, wherein a wire receiving channel (8) is provided in the interior of the shock absorber in the direction of its central axis.

10. A method of damping a measurement while drilling instrument, characterized in that a vibration damper is mounted directly on the body of the measurement while drilling instrument, using a vibration damper according to any one of claims 1-9.