Streamline deepwater node piezoelectric detector and marine seismic node

Abstract

The invention relates to the field of deepwater geophysical prospecting equipment, and discloses a streamline deepwater node piezoelectric detector and a marine seismic node. The piezoelectric detector comprises a detection assembly, a connector and a sound transmission layer, the sound transmission layer is connected with the connector, the detection assembly comprises a piezoelectric ceramic tube and an end cover, the piezoelectric ceramic tube and the connector are coaxial, and the end cover and the connector are arranged at an interval. The marine seismic node comprises the piezoelectric detector. The piezoelectric geophone provided by the invention adopts a streamline arrangement mode, the water flow impact resistance of the piezoelectric geophone is improved, meanwhile, the piezoelectric ceramic tubes and the connectors are arranged at intervals, and after vibration of nodes is transmitted to the connectors, the vibration cannot be transmitted to the piezoelectric ceramic tubes or a small amount of vibration is transmitted to the piezoelectric ceramic tubes, so that the vibration resistance of the piezoelectric geophone is improved. Therefore, the piezoelectric ceramic tube is not influenced by node vibration or is slightly influenced by node vibration, the quality of data collected by the piezoelectric detector can be improved, and the quality of later seismic profile data processing is improved.

Description

Technical Field

[0001] The invention relates to the field of deepwater geophysical exploration equipment, and in particular to a streamlined deepwater node piezoelectric geophone and an ocean seismic node. Background Art

[0002] Offshore oil exploration and acquisition technologies are mainly divided into offshore towed cable acquisition technology, submarine cable acquisition technology, submarine seismograph, and submarine node acquisition technology. Among them, the submarine node acquisition technology is to record the seismic signals excited by the source ship in the seawater and reflected by the stratum interface under the seabed through node seismographs deployed on the seabed.

[0003] Compared with other acquisition technologies, it has the following advantages: First, it is less affected by marine facilities and can carry out seismic acquisition work in areas with dense production platforms and other obstacles at sea where TS cannot be implemented; second, it completely gets rid of the constraints of cables and can realize seismic data acquisition with large offset distance and wide azimuth; third, compared with seafloor seismometers, seafloor node seismometers are cheaper and more convenient and accurate to deploy.

[0004] The node seismometer on the seabed is a four-component acquisition equipment. The piezoelectric detector is a core component of the front-end acquisition in the seabed node. It uses the piezoelectric effect of the piezoelectric element to convert the sound pressure signal in the seawater into an electrical signal. At present, the mainstream piezoelectric detectors on the market have a large radial size, resulting in poor resistance to water flow impact. At the same time, the vibration of the node will be directly transmitted to the detection component of the piezoelectric detector, affecting the quality of the seabed node data acquisition, and then affecting the quality of the subsequent seismic profile data processing. Summary of the invention

[0005] In order to solve the above technical problems or at least partially solve the above technical problems, the present invention provides a streamlined deep-water node piezoelectric detector and an ocean seismic node.

[0006] The present invention provides a streamlined deep-water node piezoelectric detector, comprising a detection component, a connector and a sound-transmitting layer, wherein the sound-transmitting layer is connected to the end of the connector and forms a cavity inside the sound-transmitting layer, the detection component comprises a piezoelectric ceramic tube arranged inside the cavity and end covers for sealing the two ends of the piezoelectric ceramic tube, wherein one of the end covers is provided with two electrodes, wherein one electrode is connected to the inner wall of the piezoelectric ceramic tube, and the other electrode is connected to the outer wall of the piezoelectric ceramic tube, and the two electrodes are connected to a circuit module through a cable, wherein the piezoelectric ceramic tube is coaxial with the connector and the end cover provided with the electrodes and the connector are spaced apart along the axial direction of the piezoelectric ceramic tube.

[0007] Optionally, a support rod is passed through the interior of the piezoelectric ceramic tube, and two ends of the support rod are respectively connected to the two end covers.

[0008] Optionally, a first connection hole connected to the support rod and a second connection hole for connecting to the two electrodes are provided on the end cap, and the two second connection holes are symmetrically arranged with respect to the first connection hole along the axial direction of the end cap.

[0009] Optionally, a receiving cavity is formed at the end of the connector head, and the end of the electrode can extend into the receiving cavity so that the electrode is connected to the cable in the receiving cavity.

[0010] Optionally, a fixing layer is formed inside the receiving cavity, and the cable passes through the fixing layer.

[0011] Optionally, one end of the support rod passes through the end cap and extends into the fixing layer.

[0012] Optionally, a first sealing groove is provided on the outer periphery of the end of the connector head close to the piezoelectric ceramic tube, and a first sealing ring matching the first sealing groove is provided on the inner wall of the sound transmission layer.

[0013] Optionally, a second sealing groove is provided on the outer periphery of the end of the connector head far from the piezoelectric ceramic tube, and the second sealing groove is used to connect with the second sealing ring on the marine seismic node.

[0014] Optionally, the sound transmission layer adopts a columnar structure, and the end of the sound transmission layer is hemispherical.

[0015] Optionally, the sound transmission layer is formed by pouring.

[0016] Optionally, the thickness of the sound transmission layer is 2 - 3 mm.

[0017] Optionally, the distance between the end of the piezoelectric ceramic tube and the end of the connector head is 5 - 10 mm.

[0018] The present invention also provides a marine seismic node, including the streamlined deep - water node piezoelectric geophone described in any one of the above.

[0019] The technical solutions provided by the embodiments of the present invention have the following advantages compared with the prior art:

[0020] The piezoelectric geophone provided by the present invention adopts a streamlined arrangement, which can effectively reduce the size along the radial direction of the piezoelectric geophone, increase the anti-water-flow impact ability of the piezoelectric geophone. At the same time, the piezoelectric ceramic tube and the connector are arranged at intervals. After the vibration of the node is transmitted to the connector, the vibration will not be transmitted to the piezoelectric ceramic tube or will be transmitted to the piezoelectric ceramic tube in a small amount. Furthermore, the piezoelectric ceramic tube is not affected by the node vibration or is less affected by the node vibration, thereby increasing the quality of the data collected by the piezoelectric geophone and the quality of the subsequent seismic profile data processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings herein are incorporated into and constitute a part of this specification, showing embodiments consistent with the present invention and, together with the specification, are used to explain the principles of the present invention.

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0023] Figure 1 It is a schematic structural diagram of the streamlined deep-water node piezoelectric geophone according to the embodiment of the present invention;

[0024] Figure 2 It is a sectional view of the streamlined deep-water node piezoelectric geophone according to the embodiment of the present invention;

[0025] Figure 3 It is a schematic structural diagram of the connector according to the embodiment of the present invention.

[0026] DESCRIPTION OF THE REFERENCE NUMERALS

[0027] 1. Detection assembly; 11. Piezoelectric ceramic tube; 12. First end cap; 13. Second end cap; 14. Electrode; 15. Support rod; 151. First connecting rod; 152. Second connecting rod;

[0028] 2. Connector; 21. First sealing groove; 22. Second sealing groove; 23. Twisting block;

[0029] 3. Acoustic transmission layer;

[0030] 4. Cable. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] In order to be able to more clearly understand the above objects, features, and advantages of the present invention, the following will further describe the solution of the present invention. It should be noted that, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0032] The following description sets forth many specific details to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein; obviously, the implementation methods in the specification are only part of the implementation methods of the present invention, rather than all of the implementation methods.

[0033] Combination Figure 1 and Figure 2 As shown, the streamlined deep-water node piezoelectric detector provided in the embodiment of the present invention includes a detection component 1, a connector 2 and a sound-transmitting layer 3, wherein the sound-transmitting layer 3 is connected to the end of the connector 2 and forms a cavity inside the sound-transmitting layer 3, wherein the cavity inside the sound-transmitting layer 3 partially accommodates the end of the connector 2, and the other part is used to accommodate the detection component 1, so that the detection component 1 and the connector 2 are arranged opposite to each other in the cavity. The sound-transmitting layer 3 has good sound permeability and can protect the detection component 1. The sound-transmitting layer 3 is preferably made of polyurethane material, and the sound-transmitting layer 3 is formed by pouring the polyurethane material to ensure the sealing effect, and the polyurethane material has good sound permeability.

[0034] The detection assembly 1 includes a piezoelectric ceramic tube 11 disposed inside a cavity and end caps for sealing both ends of the piezoelectric ceramic tube 11. The detection assembly 1 is used to sense seismic exploration signals. Among them, piezoelectric ceramics have a piezoelectric effect. When force or pressure is applied, electric charge or voltage is generated. Therefore, piezoelectric ceramics have important applications in the field of sensors.

[0035] For example, piezoelectric ceramics can be used in pressure sensors to measure the size of external pressure by measuring the change in charge or voltage. It is a permanent component in the field of sensors, and its working principle is not described in detail here. The two ends of the piezoelectric ceramic tube 11 are open, and there are two end caps, which are respectively arranged at the two ends of the piezoelectric ceramic tube 11 to seal the two openings of the piezoelectric ceramic tube 11.

[0036] Specifically, the piezoelectric ceramic tube 11 has a first end and a second end corresponding to each other. Figure 2 Taking the direction shown as an example, the left end of the piezoelectric ceramic tube 11 is the first end of the piezoelectric ceramic tube 11, and the right end of the piezoelectric ceramic tube 11 is the second end of the piezoelectric ceramic tube 11. The end cap is divided into a first end cap 12 and a second end cap 13, the first end cap 12 is used to seal the first end of the piezoelectric ceramic tube 11, and the second end cap 13 is used to seal the second end of the piezoelectric ceramic tube 11, wherein the first end cap 12 is used to seal the first end of the piezoelectric ceramic tube 11 and the second end cap 13 is used to seal the second end of the piezoelectric ceramic tube 11 is not limited and can be designed according to actual needs.

[0037] Two electrodes 14 are provided on one of the end caps, specifically, two electrodes 14 are provided on the second end cap 13. The design of the two electrodes 14 is not limited and can be designed according to actual requirements. One of the electrodes 14 is connected to the inner wall of the piezoelectric ceramic tube 11, and the other electrode 14 is connected to the outer wall of the piezoelectric ceramic tube 11. The two electrodes 14 are connected to the circuit module through the cable 4.

[0038] Specifically, one of the inner wall and the outer wall of the piezoelectric ceramic tube 11 serves as the positive electrode and the other serves as the negative electrode. Among them, when the inner wall of the piezoelectric ceramic tube 11 serves as the positive electrode, the outer wall of the piezoelectric ceramic tube 11 serves as the negative electrode, and when the inner wall of the piezoelectric ceramic tube 11 serves as the negative electrode, the outer wall of the inner wall of the piezoelectric ceramic tube 11 serves as the positive electrode. It can be seen that the distribution method of the positive and negative electrodes of the piezoelectric ceramic tube 11 is not limited and can be selected according to the manufacturing difficulty.

[0039] Among them, the piezoelectric ceramic tube 11 is coaxial with the connector 2, and the end cap provided with the electrode 14 is spaced from the connector 2 along the axial direction of the piezoelectric ceramic tube 11. Specifically, the axis of the piezoelectric ceramic tube 11 coincides with the axis of the connector 2, and the second end cap 13 is spaced from the connector 2 along the axial direction of the piezoelectric ceramic tube 11 to avoid direct contact between the connector 2 and the second end cap 13, and further avoid direct contact between the connector 2 and the piezoelectric ceramic tube 11.

[0040] Under this design method, the acoustic transmission layer 3 can be formed by casting. Coaxially arranging the piezoelectric ceramic tube 11 and the connector 2 can, on the one hand, make the thickness of the cast acoustic transmission layer 3 uniform, so that the acoustic transmission layer 3 has good pressure resistance, so that the acoustic transmission layer 3 can play a good protective role for the detection component 1. On the other hand, it avoids increasing the radial size of the piezoelectric detector to increase the anti-water flow impact ability of the piezoelectric detector. The piezoelectric ceramic tube 11 and the connector 2 are arranged at intervals so that after the vibration of the node is transmitted to the connector 2, the vibration will not be transmitted to the piezoelectric ceramic tube 11 or will be transmitted to the piezoelectric ceramic tube 11 in a small amount, avoiding affecting the use of the piezoelectric ceramic tube 11.

[0041] The piezoelectric detector provided by the present invention adopts a streamlined setting method, which can effectively reduce the size along the radial direction of the piezoelectric detector and increase the anti-water flow impact ability of the piezoelectric detector. At the same time, the piezoelectric ceramic tube 11 and the connector 2 are arranged at intervals. After the vibration of the node is transmitted to the connector 2, the vibration will not be transmitted to the piezoelectric ceramic tube 11 or will be transmitted to the piezoelectric ceramic tube 11 in a small amount. As a result, the piezoelectric ceramic tube 11 is not affected by the node vibration or is less affected by the node vibration, thereby increasing the quality of the data collected by the piezoelectric detector and increasing the quality of the subsequent seismic profile data processing. In addition, the piezoelectric detector under this design method can be applied to seismic exploration in deeper and more complex waters, improving the quality of seismic profile data processing.

[0042] As a feasible implementation, the inner wall of the piezoelectric ceramic tube 11 serves as the positive electrode, and the outer wall of the piezoelectric ceramic tube 11 serves as the negative electrode, which is achieved by plating silver on the inner and outer walls of the piezoelectric ceramic tube 11. Among them, the method of silver plating and the method of using the inner and outer walls of the piezoelectric ceramic tube 11 as the positive and negative electrodes respectively are conventional techniques. Therefore, the construction method and principle are not described in detail here. The reason for using silver plating is that silver has good electrical conductivity and excellent chemical stability, and is suitable for use as the electrode 14 material of the piezoelectric ceramic tube 11. Specifically, there are the following reasons:

[0043] 1. Electrical conductivity: Silver is one of the best electrical conductors with very low resistance. By plating silver electrodes 14 on the piezoelectric ceramic tube 11, good current conduction and electrode 14 connection can be provided.

[0044] 2. Interface effect: The interface between silver and the piezoelectric ceramic tube 11 has a low contact resistance and electrode 14 contact characteristics. The plating of silver electrodes 14 can provide good contact between the electrode 14 and the ceramic and reduce resistance loss.

[0045] 3. Chemical stability: Silver can maintain good chemical stability under common environmental conditions and is not easily oxidized or corroded. This is crucial for protecting the piezoelectric ceramic electrode 14 from the influence of the external environment and ensuring the long-term stability of the electrode 14 performance.

[0046] 4. Anti-oxidation layer: A dense oxidation layer can form on the outer layer of silver, which helps to protect the ceramic surface from the influence of oxygen and humid environment. This is crucial for improving the service life and reliability of the piezoelectric ceramic element. In the application of piezoelectric ceramics, using silver-plated electrodes 14 can provide better electrical performance, stability and reliability, and ensure the effective exertion of the piezoelectric effect.

[0047] In some embodiments, as Figure 2 shown, a support rod 15 is inserted into the piezoelectric ceramic tube 11, and both ends of the support rod 15 are respectively connected to two end caps. Among them, the connection method of both ends of the support rod 15 to the first end cap 12 and the second end cap 13 is not limited and can be designed according to actual needs. By setting the support rod 15, the piezoelectric ceramic tube 11 can be connected to the two end caps to form a stable overall structure.

[0048] The piezoelectric ceramic tube 11 is designed as a single tube and made of PZT5 material. The support rod 15 is in a cylindrical structure. At both ends of the support rod 15, a first connecting rod 151 and a second connecting rod 152 are respectively provided. The first connecting rod 151, the second connecting rod 152 and the support rod 15 are integrally formed to increase the structural strength of the support rod 15. The first connecting rod 151 is connected to the first end cap 12, and the second connecting rod 152 is connected to the second end cap 13. In order to achieve high hydrostatic pressure resistance, threads are provided on the outer peripheries of the first connecting rod 151 and the second connecting rod 152, so that the first connecting rod 151 is threadedly connected to the first end cap 12, and the second connecting rod 152 is threadedly connected to the second end cap 13, thereby enabling the first end cap 12 and the second end cap 13 to respectively cover the first end and the second end of the piezoelectric ceramic tube 11, and further realizing the connection of the first end cap 12, the second end cap 13 and the piezoelectric ceramic tube 11.

[0049] Specifically, a threaded hole is provided in the middle of the first end cap 12. The threaded hole is coaxially arranged with the first end cap 12. The first connecting rod 151 is screwed into the threaded hole to realize the connection between the first end cap 12 and the first connecting rod 151. A through hole is provided in the middle of the second end cap 13. The through hole is coaxially arranged with the second end cap 13, so that the second connecting rod 152 can pass through the through hole, and a nut is screwed on the extended end of the second connecting rod 152 to realize the connection between the second end cap 13 and the second connecting rod 152. Among them, the first end cap 12 and the second end cap 13 are made of the same material, and the material of the first end cap 12 and the second end cap 13 is zirconia.

[0050] A first connection hole for connecting with the support rod 15 and a second connection hole for connecting with the two electrodes 14 are provided on the end cap. The first connection hole here is the above-mentioned through hole. At this time, the connection between the end cap and the support rod 15 is limited by the above-mentioned nut connection method, and the second connection hole is connected to the electrode 14 by plugging. The two second connection holes are symmetrically arranged along the axial direction of the end cap relative to the first connection hole. This design method makes the two second connection holes and the first connection hole on the same straight line, and this straight line extends along the radial direction of the second end cap 13. In this application, the electrode 14 is made of a metal material with gold plating on the surface, so that it has good electrical conductivity.

[0051] The installation steps of the detection component 1 of this application are as follows:

[0052] Two electrodes 14 are installed on the second end cap 13, and the electrodes 14 are marked. One electrode 14 is the positive electrode and one electrode 14 is the negative electrode. A thin wire is welded to the lower end of the positive electrode post, and the other end of the thin wire is connected to the inner wall of the piezoelectric ceramic tube 11. The size is preferably set to 25 mm. The first end cap 12 is threadedly connected to one end of the support rod 15. The other end of the support rod 15 passes through the through holes in the piezoelectric ceramic tube 11 and the second end cap 13, and an M2 nut is screwed onto the protruding end of the support rod 15 to compress the piezoelectric ceramic tube 11, the first end cap 12 and the second end cap 13.

[0053] The negative electrode of the electrode 14 is connected to the outer wall of the piezoelectric ceramic tube 11 through a silver wire, and the silver wire is welded to the outer wall of the piezoelectric ceramic tube 11. Among them, there need to be 3 solder joints between the silver wire and the outer wall of the piezoelectric ceramic tube 11, and the welding time of each solder joint cannot exceed 10 seconds. Because the outer wall of the piezoelectric ceramic tube 11 is a silver-plated layer, if the welding time is too long, the silver layer will fall off, and the capacitance and dielectric constant will change, which will affect the sensitivity of the piezoelectric detector.

[0054] As Figure 2 shown, the end of the connector 2 is formed with a receiving cavity, and the receiving cavity is communicated with the internal cavity of the sound transmission layer 3. The receiving cavity can supply the end of the electrode 14 to extend into, so that the electrode 14 and the cable 4 are connected in the receiving cavity, effectively protecting the connection position of the electrode 14 and the cable 4.

[0055] In some embodiments, the sound transmission layer 3 is formed by pouring. The pouring liquid will enter the receiving cavity through the opening of the receiving cavity to form a fixing layer inside the receiving cavity. At this time, the fixing layer covers the part of the electrode 14 extending out of the second end cap 13, the connection between the electrode 14 and the cable 4, and the outer periphery of the part of the cable in the receiving cavity. The cable 4 passes through the fixing layer, and the cable 4 passing through the fixing layer passes through the connector 2 and is connected to the circuit module of the marine seismic node.

[0056] In some embodiments, one end of the support rod 15 passes through the end cap and extends into the fixing layer. Specifically, the second connecting rod 152 of the support rod 15 passes through the second end cap 13 and extends into the receiving cavity. The sound transmission layer 3 is formed by pouring. During the pouring process, the pouring liquid will enter the receiving cavity through the opening of the receiving cavity to form a fixing layer inside the receiving cavity, so that the fixing layer can cover the outer periphery of the second connecting rod 152. In this design, the fixing layer and the sound transmission layer 3 are an integral structure, which can increase the connection effect between the sound transmission layer 3 and the support rod 15, and at the same time can increase the connection effect between the sound transmission layer 3 and the connector 2, and at the same time can ensure the sealing effect when the cable 4 passes through the connector 2.

[0057] Further optimized, one end of the connecting head 2 close to the detection component 1 is provided with a flared end, and a first slope surface is formed on the inner wall of the flared end. A second slope surface is formed on the outer periphery of one end of the second end cap 13 close to the connecting head 2, and the first slope surface matches the second slope surface.

[0058] In this design, since the connecting head 2 and the second end cap 13 are arranged at intervals along the axial direction of the piezoelectric ceramic tube 11, the first slope surface and the second slope surface are arranged at intervals along the axial direction of the piezoelectric ceramic tube 11, and a ring-shaped fluid channel is formed directly between the first slope surface and the second slope surface. During the liquid pouring process, the liquid will enter the accommodating cavity along the fluid channel between the first slope surface and the second slope surface, so that the fluid can smoothly enter the accommodating cavity and ensure the formation effect of the fixing layer.

[0059] As Figure 3 shown, a first sealing groove 21 is provided on the outer periphery of one end of the connecting head 2 close to the piezoelectric ceramic tube 11, and a first sealing ring matching the first sealing groove 21 is provided on the inner wall of the sound transmission layer 3. This design can increase the sealing performance of the connection between the connecting head 2 and the sound transmission layer 3.

[0060] In some embodiments, the sound transmission layer 3 is formed by pouring. At this time, a first sealing groove 21 is provided on the outer periphery of one end of the connecting head 2 close to the piezoelectric ceramic tube 11. During the pouring process of the sound transmission layer 3, a first sealing ring is formed at a position corresponding to the first sealing groove 21, thereby increasing the connection strength and connection sealing performance between the sound transmission layer 3 and the connecting head 2.

[0061] Further optimized, there are two first sealing grooves 21, and the two first sealing grooves 21 are arranged at intervals along the axial direction of the connecting head 2. Correspondingly, there should also be two first sealing rings. In this design, the connection strength and connection sealing performance between the sound transmission layer 3 and the connecting head 2 can be further increased.

[0062] It can be understood that the number of the first sealing grooves 21 can be greater than two. For example, three, four, etc., and the multiple first sealing grooves 21 will be arranged at intervals along the axial direction of the connecting head 2. It can be seen that the number of the first sealing grooves 21 can be designed according to actual needs.

[0063] A second sealing groove 22 is provided on the outer periphery of the end of the connecting head 2 far from the piezoelectric ceramic tube 11, and the second sealing groove 22 is used to connect with the second sealing ring on the marine seismic node.

[0064] Specifically, the connector 2 is used as a connecting piece to install the streamlined deep-water node piezoelectric geophone on the marine seismic node. Specifically, there is an installation position on the marine seismic node. Among them, the connector 2 and the installation position of the marine seismic node can be connected by plugging or by screwing, which can be designed according to actual needs.

[0065] Among them, in order to increase the firmness of the connection, it is preferably to use the bolt connection method between the connector 2 and the installation position of the marine seismic node. At this time, there is a connecting sleeve at the installation position of the marine seismic node. The inner wall of the connecting sleeve is provided with internal threads that are threadedly connected to the connector 2, and the inner wall of the end of the connecting sleeve is provided with a second sealing groove 22. As the connector 2 is screwed onto the connecting sleeve, the second sealing ring is snapped into the second sealing groove 22 to increase the sealing effect between the connector 2 and the marine seismic node.

[0066] Specifically, continue to refer to Figure 3 , the inside of the connector 2 has a through hole, and the through hole communicates with the accommodating cavity, so that the cable 4 can sequentially pass through the accommodating cavity and the through hole and be connected to the circuit module of the marine seismic node. The diameter of the through hole is smaller than the diameter of the accommodating cavity. The through hole is only for the cable 4 to pass through, and a fixing layer needs to be formed in the accommodating cavity.

[0067] The outer periphery of the connector 2 is provided with an operating part, and both ends of the connector 2 extend out of the operating part. Taking the direction shown in Figure 2 as an example, the part of the left end of the connector 2 extending out of the operating part is connected to the sound-transmitting layer 3, and the part of the right end of the connector 2 extending out of the operating part is connected to the installation position of the marine seismic node.

[0068] Combined with Figures 1 to 3 shown, the operating part is a torsion block 23 arranged on the outer periphery of the connector 2. In order to withstand high hydrostatic pressure, the thickness of the torsion block 23 is 7-9 mm. Preferably, the thickness of the torsion block 23 is 8 mm. In order to increase the convenience of operation, the outer peripheral structure of the torsion block 23 can be designed as a hexagon, which is convenient for manual or external tool operation of the torsion block 23 to screw the connector 2 by rotating the torsion block 23, facilitating the connection between the connector 2 and the marine seismic node. It can be understood that the torsion block 23 can also adopt other polygonal structures, as long as it is convenient for the staff to operate or for the staff to be able to operate with the help of external tools.

[0069] Further optimized, taking the direction shown in Figure 2 as an example, a sealing card slot can be provided at the right end of the torsion block 23. Correspondingly, a sealing block can also be provided at the corresponding position of the installation position of the marine seismic node. In this design method, during the screwing process of the torsion block 23, the sealing block is inserted into the sealing card slot until the end of the sealing block is in full contact with the bottom of the sealing card slot, and the torsion block 23 is screwed in place to achieve the sealed connection between the torsion block 23 and the installation position of the marine seismic node.

[0070] Further optimized, in order to further increase the sealing effect, a sealing gasket can be provided at the bottom of the sealing card slot, so that after the torsion block 23 is screwed in place, the end of the sealing block supports on the sealing gasket.

[0071] The connector 2 at the right end of the torsion block 23 is designed in a cylindrical shape. The outer periphery of this part of the connector 2 has a second sealing groove 22 and threads, and the size of this part of the connector 2 is adapted to the fixed position size of the piezoelectric geophone reserved by the marine seismic node, which is convenient for better connection. The connector 2 at the left end of the torsion block 23 is also designed in a cylindrical shape. The outer periphery of this part of the connector 2 has two first sealing grooves 21, and this part of the connector 2 is connected to the detection component 1 through an acoustic transmission layer 3 made of polyurethane material, and the central axes of the connector 2 and the detection component 1 are kept coincident.

[0072] The assembled detection component 1 (the piezoelectric ceramic tube 11 and two end caps are connected by a support rod 15) is connected to the cable 4, and the cable 4 then passes through the connector 2. In order to achieve a better coupling effect, a certain distance needs to be reserved between the detection component 1 and the connector 2, and the detection component 1 and the connector 2 need to be kept perpendicular. This process is realized by placing the detection component 1 and the connector 2 in a one-time casting mold, melting the polyurethane material at a high temperature and then cooling and shaping. The streamlined deep-water node piezoelectric geophone designed in this way has a small volume, a simple process, high resistance to high hydrostatic pressure, and low noise.

[0073] In some embodiments, the cable 4 of the present application is made of a material resistant to high temperature and high pressure, because during the casting process, the polyurethane must be melted at a temperature of 80°. The cable 4 is a two-core cable 4 with a shielding layer. One end is connected to the positive and negative electrodes 14 of the detection component 1, and the other end needs to pass through the connector 2 and then be connected to the circuit module of the marine seismic node through a three-core connector to achieve the purpose of transmitting and collecting data.

[0074] Specifically, the cable 4 has a white wire and a blue wire. The white wire of the cable 4 is connected to the positive electrode, and the blue wire is connected to the negative electrode. During the welding process, an insulating sleeve must be provided at each welding point, otherwise the insulation resistance between the positive and negative electrodes of the piezoelectric geophone and the connector 2 will become smaller, resulting in a decrease in the sensitivity of the piezoelectric geophone. The other end of the cable 4 needs to pass through the connector 2 and then be connected to the circuit module of the marine seismic node through a three-core connector. In the three-core connector, pin 1 is the negative electrode, pin 2 is the positive electrode, and pin 3 is the shielding layer. This can greatly reduce the basic noise of the acquisition channel of the circuit module of the marine seismic node and improve the quality of the collected data.

[0075] In some embodiments, the acoustic transmission layer 3 of the present application has the functions of withstanding high hydrostatic pressure, protecting the detection component 1, and transmitting vibration to sense acoustic signals. The acoustic transmission layer 3 is closely connected to the detection component 1 of the piezoelectric detector, maintaining good coupling, and can completely transmit the seismic wave signals in water detected by the piezoelectric detector to the detection component 1 of the piezoelectric detector. The thickness of the acoustic transmission layer 3 depends on the sensitivity of the piezoelectric detector. The thinner the acoustic transmission layer 3, the higher the sensitivity of the piezoelectric detector. On the contrary, the thicker the acoustic transmission layer 3, the lower the sensitivity of the piezoelectric detector. At the same time, the thinner the acoustic transmission layer 3, the lower the protection intensity for the piezoelectric detector. Therefore, it is necessary to balance the relationship between the two. Among them, the thickness of the acoustic transmission layer 3 is 2-3 mm.

[0076] The shape of the acoustic transmission layer 3 adopts a columnar structure, and the end of the acoustic transmission layer 3 is hemispherical, that is, the end of the acoustic transmission layer 3 is designed as a hemispherical shape. This kind of piezoelectric detector not only has strong resistance to water flow impact, can withstand high hydrostatic pressure, but also can reduce noise, and is more suitable for the needs of deep-water exploration.

[0077] The acoustic transmission layer 3 is formed by pouring. Under this design method, the acoustic transmission layer 3 fits well with the detection component 1, maintains good coupling, and can completely transmit the seismic wave signals in water detected by the piezoelectric detector to the detection component 1 of the piezoelectric detector.

[0078] The formation of the acoustic transmission layer 3 needs to be realized through a secondary casting mold. In order to achieve the effects of high pressure resistance, sealing, and acoustic transmission, a mechanical simulation software is used to simulate and analyze the thickness of the acoustic transmission layer 3. The thickness of the acoustic transmission layer 3 is controlled within 2-3 mm, which can meet the design requirements. Combining with the mechanical structure design of the marine seismic node, the thickness of the acoustic transmission layer 3 of the piezoelectric detector is preferably set to 3 mm.

[0079] In some embodiments, the distance between the end of the piezoelectric ceramic tube 11 and the end of the connector 2 is 5-10 mm. For the streamlined deep-water node piezoelectric detector with this kind of distance, due to the existence of this gap, the connector 2 will not affect the normal use of the piezoelectric ceramic tube 11, and it avoids increasing the overall length of the streamlined deep-water node piezoelectric detector, making the volume of the streamlined deep-water node piezoelectric detector smaller, reducing the space occupation when installed on the marine seismic node, and meeting the use requirements.

[0080] Example 1, one of the assembly methods of the streamlined deep-water node piezoelectric detector provided by the present application is as follows:

[0081] Step S1: Install two electrodes 14 on the second end cap 13, label one electrode 14 as the positive electrode and the other as the negative electrode. Weld a thin wire to the lower end of the positive electrode post, and connect the other end of the thin wire to the inner wall of the piezoelectric ceramic tube 11. Thread-connect the first end cap 12 to one end of the support rod 15. The other end of the support rod 15 passes through the through holes in the piezoelectric ceramic tube 11 and the second end cap 13, and use an M2 nut to screw onto the protruding end of the support rod 15 to compress the piezoelectric ceramic tube 11, the first end cap 12, and the second end cap 13. Connect the negative electrode of the electrode 14 to the outer wall of the piezoelectric ceramic tube 11 through a silver wire, and weld the silver wire to the outer wall of the piezoelectric ceramic tube 11, thus completing the installation of the detection component 1.

[0082] Step S2: Connect the assembled detection component 1 to the cable 4. Specifically, the white wire of the cable 4 is connected to the positive electrode, and the blue wire is connected to the negative electrode. During the welding process, each solder joint must be provided with an insulating sleeve. The end of the cable 4 far from the detection component 1 passes through the connector 2 and is then connected to the circuit module of the marine seismic node through a three-core connector.

[0083] Step S3: After the cable 4 is connected, leave a certain distance between the detection component 1 and the connector 2, and ensure that the detection component 1 is perpendicular to the connector 2. Then place the detection component 1 and the connector 2 in this state in a one-time casting mold for casting. The casting material is polyurethane to form a fixing layer in the receiving cavity of the connector 2. The fixing layer wraps around the outer periphery of the cable 4 and the electrode 14, and at the same time, a sound-transmitting layer 3 can be formed between the detection component 1 and the connector 2.

[0084] Embodiment 2: Another assembly method of the streamlined deep-water node piezoelectric detector provided in the present application is as follows:

[0085] Step S1: Install two electrodes 14 on the second end cap 13, and label the electrodes 14, one electrode 14 as the positive electrode and the other as the negative electrode. Weld a thin wire to the lower end of the positive electrode post, and connect the other end of the thin wire to the inner wall of the piezoelectric ceramic tube 11. Thread-connect the first end cap 12 to one end of the support rod 15. The other end of the support rod 15 passes through the through holes in the piezoelectric ceramic tube 11 and the second end cap 13, and use an M2 nut to screw onto the protruding end of the support rod 15 to compress the piezoelectric ceramic tube 11, the first end cap 12, and the second end cap 13. Connect the negative electrode of the electrode 14 to the outer wall of the piezoelectric ceramic tube 11 through a silver wire, and weld the silver wire to the outer wall of the piezoelectric ceramic tube 11, thus completing the installation of the detection component 1.

[0086] Step S2: Connect the assembled detection component 1 to the cable 4. Specifically, the white wire of the cable 4 is connected to the positive electrode, and the blue wire is connected to the negative electrode. During the welding process, an insulating sleeve must be provided for each solder joint. One end of the cable 4 far from the detection component 1 passes through the connector 2 and is connected to the circuit module of the marine seismic node through a three-core connector.

[0087] Step S3: After the cable 4 is connected, a certain distance should be reserved between the detection component 1 and the connector 2, and the detection component 1 needs to be perpendicular to the connector 2. Then, place the detection component 1 and the connector 2 in this state in a primary casting mold for casting. The casting material is polyurethane to form a fixing layer in the accommodating cavity of the connector 2. The fixing layer wraps around the outer periphery of the cable 4 and the electrode 14, and at the same time, a preliminary sound-transmitting layer 3 can be formed between the detection component 1 and the connector 2.

[0088] Step S4: Then, place the component obtained in Step S3 into a secondary casting mold, and cast polyurethane here to form a sound-transmitting layer 3 with a preset thickness.

[0089] The present invention also provides a marine seismic node, including the streamlined deep-water node piezoelectric geophone of any one of the above. The streamlined deep-water node piezoelectric geophone here includes all the technical features of the above-mentioned streamlined deep-water node piezoelectric geophone. Among them, the marine seismic node is a multi-component seismograph located on the seabed that can independently collect and record seismic signals. It has the characteristics of wide azimuth, high coverage, high construction efficiency, multi-component recording, and strong feasibility in complex terrains, and is the mainstream method for current marine seismic acquisition.

[0090] The marine seismic node should also include a battery module and a circuit structure. The circuit structure has a circuit module and a three-component geophone. The battery module is used to provide electrical energy for components such as the three-component geophone. The circuit module is connected to the three-component geophone and the streamlined deep-water node piezoelectric geophone of the present application by wires.

[0091] Specifically, the circuit module is connected to the electrode 14 of the streamlined deep-water node piezoelectric geophone through the cable 4. Among them, the three-component geophone is a special geophone used in multi-wave exploration. Different from the single-component conventional seismic geophone, each geophone is equipped with three mutually perpendicular sensors to record three components of the particle vibration velocity vector, and is used to record longitudinal waves, transverse waves, and converted waves simultaneously. The three-component geophone is a conventional technology in this field. Therefore, its structure and working principle are not described in detail here. In addition, the connection methods between this kind of circuit module, battery module and each component are conventional technologies in this field. Therefore, their specific structures and working principles are not described in detail here.

[0092] It should be noted that in this text, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising said element.

[0093] The above are only specific embodiments of the present invention, enabling those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments described herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A streamlined deep - water node piezoelectric geophone, characterized in that, it includes a geophone component (1), a connector (2) and a sound - transmitting layer (3). The sound - transmitting layer (3) is connected to the end of the connector (2) and forms a cavity inside the sound - transmitting layer (3). The geophone component (1) includes a piezoelectric ceramic tube (11) arranged inside the cavity and end caps for sealing both ends of the piezoelectric ceramic tube (11). One of the end caps is provided with two electrodes (14). One of the electrodes (14) is connected to the inner wall of the piezoelectric ceramic tube (11), and the other electrode (14) is connected to the outer wall of the piezoelectric ceramic tube (11). The two electrodes (14) are connected to a circuit module through a cable (4). Among them, the piezoelectric ceramic tube (11) is coaxial with the connector (2), and the end cap provided with the electrode (14) is spaced from the connector (2) along the axial direction of the piezoelectric ceramic tube (11).

2. The streamlined deep - water node piezoelectric geophone according to claim 1, characterized in that, a support rod (15) is inserted inside the piezoelectric ceramic tube (11), and both ends of the support rod (15) are respectively connected to the two end caps.

3. The streamlined deep - water node piezoelectric geophone according to claim 2, characterized in that, the end cap is provided with a first connection hole for connecting to the support rod (15) and a second connection hole for connecting to the two electrodes (14). The two second connection holes are symmetrically arranged relative to the first connection hole along the axial direction of the end cap.

4. The streamlined deep - water node piezoelectric geophone according to claim 2, characterized in that, the end of the connector (2) forms a receiving cavity, and the end of the electrode (14) can extend into the receiving cavity so that the electrode (14) is connected to the cable (4) inside the receiving cavity.

5. The streamlined deep - water node piezoelectric geophone according to claim 4, characterized in that, a fixing layer is formed inside the receiving cavity, and the cable (4) passes through the fixing layer.

6. The streamlined deep - water node piezoelectric geophone according to claim 5, characterized in that, one end of the support rod (15) passes through the end cap and extends into the fixing layer.

7. The streamlined deep - water node piezoelectric geophone according to claim 1, characterized in that, a first sealing groove (21) is provided on the outer periphery of the end of the connector (2) close to the piezoelectric ceramic tube (11), and a first sealing ring matching the first sealing groove (21) is provided on the inner wall of the sound - transmitting layer (3).

8. The streamlined deep - water node piezoelectric geophone according to claim 1, characterized in that, a second sealing groove (22) is provided on the outer periphery of the end of the connector (2) far from the piezoelectric ceramic tube (11), and the second sealing groove (22) is used to connect to a second sealing ring on a marine seismic node.

9. The streamlined deep - water node piezoelectric geophone according to claim 1, characterized in that, the sound - transmitting layer (3) adopts a columnar structure, and the end of the sound - transmitting layer (3) is hemispherical.

10. The streamlined deep - water node piezoelectric geophone according to claim 1, wherein, the acoustic transmission layer (3) is formed by pouring.

11. The streamlined deep - water node piezoelectric geophone according to claim 1, wherein, the thickness of the acoustic transmission layer (3) is 2 - 3 mm.

12. The streamlined deep - water node piezoelectric geophone according to claim 1, wherein, the distance between the end of the piezoelectric ceramic tube (11) and the end of the connector (2) is 5 - 10 mm.

13. An ocean seismic node, wherein, it includes the streamlined deep - water node piezoelectric geophone according to any one of claims 1 to 12.

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