Drilling pipe and sound-absorbing structure

Abstract

The present invention provides a drilling string and a sound-absorbing structure, the drilling string comprising: a pressure wave detection device, a drill collar and a drill bit connected in sequence from top to bottom, the drill collar is provided with a pulse generating device and a sound-absorbing structure, the pulse generating device and the sound-absorbing structure are distributed in sequence from top to bottom; the sound-absorbing structure comprises a damping sleeve, the damping sleeve is fixed to the inner wall of the drill collar, and the fluid in the drill collar can flow through the damping sleeve. Through the present invention, the technical problem that the pulse signal in the well is interfered by noise when it is transmitted upward, which makes it difficult for the ground system to resolve the pulse signal is alleviated.

Description

Technical Field

[0001] The invention relates to the technical field of drilling equipment, and in particular to a drilling pipe column and a sound-absorbing structure. Background Art

[0002] In the drilling string, the downhole instrument transmits pulse signals upward, and the ground system receives and interprets the pulse signals, thereby transmitting signals from the downhole to the ground, making it easier to understand the downhole conditions on the ground. However, noise is generated in the drilling string, and due to the interference of noise, it is difficult for the ground system to interpret the pulse signals. Summary of the invention

[0003] The purpose of the present invention is to provide a drilling pipe and a sound-absorbing structure to alleviate the technical problem that when the pulse signal from the well is transmitted upward, it is interfered by noise, which makes it difficult for the ground system to calculate the pulse signal.

[0004] The above-mentioned purpose of the present invention can be achieved by adopting the following technical solutions:

[0005] The present invention provides a drilling pipe column, comprising: a pressure wave detection device, a drill collar and a drill bit connected in sequence from top to bottom, the drill collar is provided with a pulse generating device and a silencer structure, the pulse generating device and the silencer structure are distributed in sequence from top to bottom; the silencer structure comprises a damping sleeve, the damping sleeve is fixedly arranged on the inner wall of the drill collar, and the fluid in the drill collar can flow through the damping sleeve.

[0006] In a preferred embodiment, the silencer structure includes a support tube, a side wall of the support tube is provided with a connecting structure, the damping sleeve is sleeved outside the support tube, and the fluid in the inner cavity of the support tube can flow to the inner wall of the damping sleeve through the connecting structure.

[0007] In a preferred embodiment, the communication structure includes a plurality of through holes distributed on the side wall of the support tube.

[0008] In a preferred embodiment, the communication structure includes a plurality of through grooves extending along the axial direction of the support tube.

[0009] In a preferred embodiment, a cylinder groove is provided on the outer wall of the support cylinder, and the damping sleeve is arranged in the cylinder groove.

[0010] In a preferred embodiment, the inner wall of the drill collar is provided with a drill collar groove, and the support tube is installed in the drill collar groove.

[0011] In a preferred embodiment, the drill collar comprises an upper drill collar and a lower drill collar, the drill collar groove is provided in the upper drill collar, the lower drill collar is connected to the lower end of the upper drill collar, and the upper end of the lower drill collar abuts against the support tube; the drill bit is connected to the lower end of the lower drill collar.

[0012] In a preferred embodiment, an upper guide portion is provided at the upper end of the inner wall of the support tube, and the inner diameter of the upper guide portion gradually decreases from top to bottom; a lower guide portion is provided at the lower end of the inner wall of the support tube, and the inner diameter of the lower guide portion gradually increases from top to bottom.

[0013] In a preferred embodiment, the damping sleeve is made of damping rubber or airbag.

[0014] The present invention provides a muffler structure, which is applied to the above-mentioned drilling pipe column. The muffler structure comprises a damping sleeve, which can be fixed on the inner wall of the drill collar, and the fluid in the drill collar can flow through the damping sleeve.

[0015] The characteristics and advantages of the present invention are:

[0016] The pulse generator located downhole sends out a pulse signal, which is transmitted upward through the mud in the well, and the pressure wave detection device located on the ground receives the pulse signal. In the drilling pipe string, the damping sleeve is arranged between the pulse generator and the drill bit, and the mud flows through the drill bit, the damping sleeve and the pulse generator. The pressure fluctuation generated at the drill bit forms noise transmitted through the mud. When the mud flows through the damping sleeve, the damping sleeve will produce a pre-compression amount under the pressure of the mud, and can be further compressed when the pressure of the mud increases, thereby slowing down the increase in pressure; and when the pressure of the mud decreases, the damping sleeve rebounds, filling a part of the liquid space of the mud flow channel, reducing the pressure reduction value, thereby reducing the pressure fluctuation, reducing the noise energy transmitted upward by the drill bit, reducing the pulse noise, improving the signal-to-noise ratio, and improving the decoding success rate, alleviating the technical problem that the pulse signal downhole is interfered by noise when it is transmitted upward, which makes it difficult for the ground system to solve the pulse signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 A schematic diagram of the structure of the drilling string provided by the present invention;

[0019] Figure 2a for Figure 1 The schematic diagram of the drilling string placed in the formation is shown;

[0020] Figure 2b for Figure 1 A schematic diagram of the connection between the muffler structure and the drill collar in the drilling string is shown;

[0021] Figure 3 for Figure 1 The structural schematic diagram of the first embodiment of the sound-absorbing structure in the drilling pipe string shown;

[0022] Figure 4 for Figure 1 The schematic structural diagram of the second embodiment of the sound-absorbing structure in the drilling pipe string is shown.

[0023] Description of Figure Numbers:

[0024] 11. Pressure wave detection device; 12. Pulse generating device; 21. Drill bit; 22. Mud pump;

[0025] 30. drill collar; 301. drill collar groove; 31. upper drill collar; 32. lower drill collar;

[0026] 40. Noise-absorbing structure; 41. Damping sleeve;

[0027] 42. Support cylinder; 421. Upper flow guide; 422. Lower flow guide; 43. Cylinder groove;

[0028] 44. connecting structure; 441. through groove; 442. through hole;

[0029] 50. Strata. DETAILED DESCRIPTION

[0030] 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 described embodiments 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 creative work are within the scope of protection of the present invention.

[0031] Embodiment 1

[0032] The inventors have found that the noise in the drilling string that affects the pulse signal mainly comes from the water hole at the drill bit 21. The noise is generated by random pressure fluctuations caused by the obstruction of stones and the change of pumping pressure.

[0033] The present invention provides a drilling string, such as Figure 1 As shown, the drilling string includes: a pressure wave detection device 11, a drill collar 30 and a drill bit 21 connected in sequence from top to bottom, the drill collar 30 is provided with a pulse generating device 12 and a silencer structure 40, and the pulse generating device 12 and the silencer structure 40 are distributed in sequence from top to bottom; the silencer structure 40 includes a damping sleeve 41, and the damping sleeve 41 is fixed to the inner wall of the drill collar 30, and the fluid in the drill collar 30 can flow through the damping sleeve 41.

[0034] The pulse generator 12 located downhole sends out a pulse signal, and the pulse signal is transmitted upward through the mud in the well, and the pressure wave detection device 11 located on the ground receives the pulse signal. In the drilling pipe string, the damping sleeve 41 is arranged between the pulse generator 12 and the drill bit 21, and the mud flows through the drill bit 21, the damping sleeve 41 and the pulse generator 12. The pressure fluctuation generated at the drill bit 21 forms the noise transmitted through the mud. When the mud flows through the damping sleeve 41, under the pressure of the mud, the damping sleeve 41 will produce a pre-compression amount, and when the pressure of the mud increases, it can be further compressed, thereby slowing down the increase in pressure; and when the pressure of the mud decreases, the damping sleeve 41 rebounds, fills a part of the liquid space of the mud flow channel, reduces the pressure reduction value, thereby reducing the pressure fluctuation, reducing the noise energy transmitted upward by the drill bit 21, reducing the pulse noise, improving the signal-to-noise ratio, improving the decoding success rate, and alleviating the technical problem that the pulse signal downhole is interfered by noise when it is transmitted upward, which makes it difficult for the ground system to solve the pulse signal.

[0035] like Figure 1 As shown, the upper end of the drilling string is connected to a mud pump 22, which drives the mud to circulate up and down in the annulus between the string and the well wall, and in the string. The mud pump 22, the pressure wave detection device 11, the pulse generator 12 and the drill bit 21 are connected by a drill pipe, a drill collar 30 and a high-pressure hose for downhole signal transmission; the drill bit 21 drills downward into the formation 50. The pulse generator 12 and the pressure wave detection device 11 are several thousand meters apart, and the pulse pressure signal will continue to attenuate as the distance increases during the transmission process.

[0036] The mud flowing in the drill collar 30 contacts the inner wall of the damping sleeve 41, and the damping sleeve 41 absorbs the pressure fluctuation of the mud. The outer wall of the damping sleeve 41 fits the inner wall of the drill collar 30. In some cases, the inner wall of the damping sleeve 41 is exposed, that is, the inner wall of the damping sleeve 41 can contact the mud completely, so that the damping sleeve 41 has a large mud contact area, which is conducive to the damping sleeve 41 fully contacting with the mud and absorbing the pressure fluctuation of the mud.

[0037] In other cases, the sound-absorbing structure 40 includes a support tube 42, such as Figure 3 and Figure 4As shown, the side wall of the support tube 42 is provided with a connecting structure 44, and the damping sleeve 41 is sleeved outside the support tube 42. The fluid in the inner cavity of the support tube 42 can flow to the inner wall of the damping sleeve 41 through the connecting structure 44. The mud contacts the damping sleeve 41 through the connecting structure 44. The damping sleeve 41 can absorb the pressure fluctuation of the mud. At the same time, the support tube 42 can block or slow down the impact of the mud, protect the damping sleeve 41, avoid damage to the damping sleeve 41, and ensure the stability of the position of the damping sleeve 41. The support tube 42 can be made of metal materials such as steel, and the damping sleeve 41 is attached to the outside of the support tube 42.

[0038] In one embodiment of the present invention, the connecting structure 44 includes a plurality of through grooves 441 extending along the axial direction of the support tube 42, which is conducive to ensuring that the mud and the damping sleeve 41 can be in relatively sufficient contact, and the through grooves 441 extend along the axial direction, and the mud flows along the axial direction in the support tube 42, which is conducive to the damping sleeve 41 absorbing the pressure fluctuation of the mud. Figure 3 As shown, a plurality of through slots 441 may be distributed at intervals along the circumference of the support tube 42 .

[0039] The structural form of the connecting structure 44 is not limited to one. In another embodiment of the present invention, Figure 4 As shown, the communication structure 44 includes a plurality of through holes 442 distributed on the side wall of the support tube 42, through which the mud can pass to contact the damping sleeve 41. Preferably, the through holes 442 are circular holes.

[0040] The support tube 42 may be cylindrical, the damping sleeve 41 is fixed to the outer wall of the support tube 42, and the support tube 42, the damping sleeve 41 and the drill collar 30 are arranged in layers from the inside to the outside. Figure 3 As shown, the outer wall of the support cylinder 42 is provided with a cylinder groove 43, and the damping sleeve 41 is arranged in the cylinder groove 43. The cylinder groove 43 can be used to position the damping sleeve 41 to avoid axial movement of the damping sleeve 41, thereby ensuring the stability of the position of the damping sleeve 41 and facilitating the damping sleeve 41 to absorb pressure fluctuations of the mud.

[0041] Furthermore, the inner wall of the drill collar 30 is provided with a drill collar groove 301, and the support tube 42 is installed in the drill collar groove 301. The drill collar groove 301 plays a positioning role for the support tube 42 to prevent the support tube 42 and the damping sleeve 41 from moving in the axial direction. Figure 2b As shown, the opening of the drill collar groove 301 faces inward, the opening of the barrel groove 43 faces outward, the damping sleeve 41 is arranged in the barrel groove 43, and the outer wall of the damping sleeve 41 fits with the bottom wall of the drill collar groove 301.

[0042] The drill collar 30 includes an upper drill collar 31 and a lower drill collar 32. The drill collar groove 301 is provided on the upper drill collar 31. The lower drill collar 32 is connected to the lower end of the upper drill collar 31, and the upper end of the lower drill collar 32 abuts against the support tube 42. The drill bit 21 is connected to the lower end of the lower drill collar 32. Figure 2a and Figure 2b As shown, the upper drill collar 31 and the lower drill collar 32 form a stepped structure at the connection. During assembly, the lower drill collar 32 is tightened to the upper drill collar 31 through the drill collar thread buckle and presses the silencer structure 40 to limit the axial movement of the silencer structure 40, thereby improving the firmness of the structure and facilitating disassembly and assembly.

[0043] In the pipe string, the mud flows downward, flows through the upper drill collar 31 and the lower drill collar 32 in sequence; the mud flows to the drill bit 21, enters the annulus between the pipe string and the well wall, and flows upward. Further, an upper guide portion 421 is provided at the upper end of the inner wall of the support tube 42, and the inner diameter of the upper guide portion 421 gradually decreases from top to bottom; a lower guide portion 422 is provided at the lower end of the inner wall of the support tube 42, and the inner diameter of the lower guide portion 422 gradually increases from top to bottom. The mud flows into the damping sleeve 41 through the upper guide portion 421, and then flows out of the damping sleeve 41 through the lower guide portion 422 and enters the drill collar 30. The upper guide portion 421 and the lower guide portion 422 can guide the flow of the mud, which is conducive to the smooth flow of the mud through the damping sleeve 41 and the absorption of the pressure fluctuation of the mud by the damping sleeve 41.

[0044] The damping sleeve 41 absorbs energy by elasticity. The damping sleeve 41 can be made of damping rubber or airbag, which can effectively reduce the noise energy transmitted upward from the water hole of the drill bit 21, thereby reducing pulse noise, improving signal-to-noise ratio, and improving decoding success rate.

[0045] When the drilling string is implemented, the natural frequency of the muffler structure 40 can be selected according to the pressure pulsation frequency of the water hole of the drill bit 21 to optimize the pulsation absorption effect of the muffler structure 40 and improve the performance of reducing pulse noise. The natural frequency of the muffler structure 40 is mainly determined by the structural size parameters of the damping sleeve 41 and the material parameters of the damping sleeve 41, and can be determined by calculation and experiment.

[0046] Embodiment 2

[0047] like Figure 3 and Figure 4 As shown, the present invention provides a silencer structure 40 applied to the above-mentioned drilling pipe string. The silencer structure 40 includes a damping sleeve 41 . The damping sleeve 41 can be fixed to the inner wall of the drill collar 30 , and the fluid in the drill collar 30 can flow through the damping sleeve 41 .

[0048] The muffler structure 40 can be installed in the drilling pipe column, and the damping sleeve 41 is arranged between the pulse generator 12 and the drill bit 21, and the mud flows through the drill bit 21, the damping sleeve 41 and the pulse generator 12. The pressure fluctuations generated at the drill bit 21 form noise transmitted through the mud. When the mud flows through the damping sleeve 41, under the pressure of the mud, the damping sleeve 41 will produce a pre-compression amount, and when the pressure of the mud increases, it can be further compressed, thereby slowing down the increase in pressure; and when the pressure of the mud decreases, the damping sleeve 41 rebounds, filling a part of the liquid space of the mud flow channel, reducing the pressure reduction value, thereby reducing pressure fluctuations, reducing the noise energy transmitted upward by the drill bit 21, reducing pulse noise, improving the signal-to-noise ratio, and improving the decoding success rate, alleviating the technical problem that the pulse signal in the well is interfered by noise when it is transmitted upward, which makes it difficult for the ground system to solve the pulse signal.

[0049] The noise reduction structure 40 can be applied to a wireless drilling system or a rotary steering system to reduce noise interference when transmitting pulsating signals from underground to the surface.

[0050] The above are only several embodiments of the present invention. Those skilled in the art may make various changes or modifications to the embodiments of the present invention based on the contents disclosed in the application documents without departing from the spirit and scope of the present invention.

Claims

1. A drilling string, characterized in that: include: A pressure wave detection device, a drill collar and a drill bit are connected in sequence from top to bottom, the drill collar is provided with a pulse generating device and a muffler structure, the pulse generating device and the muffler structure are distributed in sequence from top to bottom; the muffler structure includes a damping sleeve, the damping sleeve is fixed to the inner wall of the drill collar, and the fluid in the drill collar can flow through the damping sleeve; The muffler structure comprises a support tube, a side wall of the support tube is provided with a connecting structure, the damping sleeve is sleeved outside the support tube, and the fluid in the inner cavity of the support tube can flow to the inner wall of the damping sleeve through the connecting structure; The communication structure includes a plurality of through holes distributed on the side wall of the support tube, or the communication structure includes a plurality of through grooves extending along the axial direction of the support tube; The outer wall of the support cylinder is provided with a cylinder groove, and the damping sleeve is arranged in the cylinder groove; The inner wall of the drill collar is provided with a drill collar groove, and the support tube is installed in the drill collar groove; The drill collar comprises an upper drill collar and a lower drill collar, the drill collar groove is provided on the upper drill collar, the lower drill collar is connected to the lower end of the upper drill collar, and the upper end of the lower drill collar abuts against the support tube; the drill bit is connected to the lower end of the lower drill collar; An upper guide portion is provided at the upper end of the inner wall of the support tube, and the inner diameter of the upper guide portion gradually decreases from top to bottom; a lower guide portion is provided at the lower end of the inner wall of the support tube, and the inner diameter of the lower guide portion gradually increases from top to bottom; The material of the damping sleeve is damping rubber or air bag.

2. A sound-absorbing structure, applied to the drilling string according to claim 1, characterized in that: The noise reduction structure comprises a damping sleeve, which can be fixedly arranged on the inner wall of the drill collar, and the fluid in the drill collar can flow through the damping sleeve.

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