Non-rotating contact signal transmission structure for measurement of parameters while drilling and its application

Abstract

The present invention discloses a non-rotating contact signal transmission structure for measuring parameters while drilling and its application. The transmission structure is arranged at the connection part of the drill pipe and the data processing box, and mainly includes two hollow discs and two groups of copper sheets. The two hollow discs are fixed on the base at the tail of the drill pipe and are coaxial with the drill pipe. The two groups of copper sheets are respectively attached back-to-back to the opposite surfaces of the two hollow discs and then tightened with springs. The hollow discs are electrically connected to the data processing box. One end of the four copper sheets is connected to the tail of the drill pipe and is electrically connected to the strain gauges attached to the drill pipe. It is required that the hollow discs remain stationary when the copper sheets rotate with the drill pipe, and insulating paint is applied at the back-to-back position of the two groups of copper sheets. The present invention solves the problem that the data processing of the measurement parameters while drilling is unstable for the data processing box of the measurement parameters while drilling due to the high-speed co-rotation of the data processing box of the measurement parameters while drilling and the drill pipe during the operation of the measurement platform while drilling.

Description

Technical Field

[0001] The present invention belongs to the test devices used in mining engineering and geotechnical engineering, especially in the field of indoor test research on in-situ sampled rocks. In order to solve the co-rotation problem between the rotating rod and the coiled tubing parameter data processing box during the process of drilling holes in the sampled rocks on the coiled tubing measurement platform, and ensure the accuracy and stability of the measurement data. Background Art

[0002] In order to ensure the safety of underground projects such as mine exploitation and tunnel excavation, it is necessary to fully understand the in-situ stress distribution state, surrounding rock characteristics, and geological conditions, etc. Due to the limitations of the underground environment and the size of the experimental equipment, many detections need to transport the taken in-situ rocks to the laboratory for relevant drilling and measurement experiments, so as to obtain various parameters of the rocks and understand the underground state. The coiled tubing measurement platform is to record the change information of various parameters during the drilling process of the drill rig, such as drilling depth, time, penetration rate, rotation speed, torque, inclination angle, etc. Analyze the data to determine the properties of underground rocks and geological conditions. Provide data support for technicians to formulate safe and reasonable construction plans.

[0003] The above-mentioned coiled tubing measurement platform includes a drill rig, a drill pipe, a drill bit, a power system, and a data processing box integrated on the drill rig base. Strain gauges are attached to the drill pipe body near the drill bit, and the data processing box is connected to the strain gauges through wires. For some of the currently sold coiled tubing measurement platforms, the data processing box and the drill pipe are fixed together. When conducting drilling experiments on in-situ rocks, when the drill pipe rotates at a high speed, in order to prevent wire entanglement, the data processing box must rotate at a high speed together with the drill pipe. Since the data processing box is filled with various components inside, the long-term centrifugal rotation will inevitably affect the working stability of the precision devices inside the data processing box, thereby affecting the accuracy of the measurement results. Furthermore, it will affect the judgment of technicians on the underground surrounding rock conditions and the in-situ stress distribution state, and affect the mining safety.

[0004] Therefore, it is necessary to release the binding between the data processing box and the drill pipe, so that the two can operate independently, and ensure the independent transmission of multiple groups of signals, so as to solve the above problems, ensure the accuracy of the measurement, and facilitate technicians to accurately analyze and judge the underground surrounding rock conditions and the in-situ stress distribution state. Summary of the Invention

[0005] In order to solve the problem of inaccurate and unstable measurement data caused by the high-speed co-rotation of the data processing box and the drill pipe during the operation of the coiled tubing measurement platform, the present invention provides a non-co-rotating contact signal transmission structure for coiled tubing parameter measurement. Through this signal transmission structure, the binding between the data processing box and the drill pipe can be released, ensuring the working stability of the precision devices inside the data processing box and the accuracy of the measurement, and facilitating technicians to accurately analyze and judge the underground surrounding rock conditions and the in-situ stress distribution state.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A non-rotating contact signal transmission structure for measuring parameters while drilling. The signal transmission realizes the signal transmission between the strain gauge at the front end of the drill pipe and the data processing box. It is characterized in that it includes two hollow discs and four copper sheets. The two hollow discs are fixed on the base at the tail of the drill pipe and are coaxial with the drill pipe. The four copper sheets are divided into two groups. The two groups of copper sheets are back-to-back and respectively attached to the opposite surfaces of the two hollow discs. The opposite surfaces of the two hollow discs are tightened with springs, so that the two groups of copper sheets are back-to-back and can be tightly attached to their respective hollow discs. The hollow discs are electrically connected to the data processing box. One end of the four copper sheets is connected to the tail of the drill pipe and is electrically connected to the strain gauge attached to the drill pipe. It is required that the hollow discs are fixed when the copper sheets rotate with the drill pipe, and insulating paint is applied at the back-to-back position of the two groups of copper sheets.

[0008] Furthermore, if the number of strain gauges at the front section of the drill pipe is large, the existing structure cannot meet the stable transmission of more signals without interference. The hollow discs are formed by integrating multiple hollow discs with different diameters. The copper sheets are also divided into multiple zones, and the number of zones of the copper sheets is the same as the number of hollow discs with different diameters. It is required that each copper sheet is only not coated with insulating paint in one zone, ensuring that each copper sheet only transmits signals to one hollow disc and will not interfere with each other.

[0009] Furthermore, to meet the simultaneous transmission of multiple groups of signals without interference, the hollow discs are formed by integrating an inner hollow disc and an outer hollow disc. The contact part between the inner and outer hollow discs is insulated. The copper sheets are also divided into two zones along with the discs. The area in contact with the inner hollow disc is called one zone, and the area in contact with the outer hollow disc is one zone. When the copper sheet needs to input signals to the inner hollow disc, the area of the copper sheet in contact with the outer hollow disc should be coated with insulating paint. Conversely, when the copper sheet needs to input signals to the outer hollow disc, the area of the copper sheet in contact with the inner hollow disc should be coated with insulating paint. At the same time, it is required that one of the group of copper sheets attached to the same hollow disc must be insulated from the outer hollow disc and one must be insulated from the inner hollow disc.

[0010] Furthermore, to increase the contact area between the copper sheet and the hollow disc and minimize the influence of friction on the shape of the copper sheet, the copper sheet is trapezoidal, with the long side of the trapezoid connected to the drill pipe and the short side of the trapezoid attached to the disc.

[0011] Furthermore, to avoid the influence of the wear of the insulating paint on the copper sheet on the stable signal transmission, the part of the copper sheet in contact with the concentric disc where the insulating paint is applied is made concave, that is, the contact area between the part of the copper sheet where the insulating paint is applied and the hollow disc is reduced.

[0012] Furthermore, there are multiple sets of the non-rotating contact signal transmission structures, and the multiple sets are connected in parallel to the tail of the drill pipe in a detachable manner to meet the transmission requirements of more signals.

[0013] Furthermore, to protect the transmission structure, it further includes a housing that wraps the hollow disk and the copper sheet therein, thereby forming a detachable integrated structure, which can be applied to solve practical engineering problems such as the entanglement of wires due to rotation.

[0014] Certainly, the present invention relates to a signal transmission structure, which implies that the hollow disk must be made of a conductive material.

[0015] The usage method of the non-rotating contact signal transmission structure of the present invention for measuring parameters while drilling is as follows:

[0016] First, connect the transmission structure to the drill pipe. The connection method is: fix a hollow connector coaxial with the drill pipe at the tail of the drill pipe. The hollow connector passes through two hollow disks, and the copper sheet is fixed on the hollow connector. The wire attached to the strain gauge at the front section of the drill pipe passes through the center of the drill pipe and the hollow connector and is connected to the copper sheet. When there are many strain gauges on the drill pipe and a single set of non-rotating contact signal transmission structures cannot meet the signal transmission requirements, thread-connect a second hollow connector at the tail of the connector, and connect the second set of non-rotating contact signal transmission structures to the drill pipe through the second hollow connector, and so on.

[0017] Then start the drill pipe power system, and the drill pipe starts to rotate at high speed. As the drill pipe advances forward, the drill bit begins to contact the rock to be measured. As the drill bit continues to advance, the strain gauges pasted at the rear end of the drill bit are deformed to generate electrical signals, which are conducted backward along the wire in the hollow drill pipe to the contact transmission structure at the rear end. The signals are output from the contact transmission structure and directly transmitted to the data processing box through the wire, and after being processed by the data processing box, they are transmitted to the computer in a wireless form for analysis.

[0018] The beneficial effects of the present invention are as follows:

[0019] 1. By redesigning the connection part between the drill pipe and the data processing box and adding a contact data transmission device, the present invention solves the problem of unstable data processing of the downhole parameter data processing box caused by the high-speed co-rotation of the downhole parameter data processing box and the drill pipe during the operation of the downhole measurement platform while ensuring stable data transmission. Ensure the reliability and accuracy of experimental data.

[0020] 2. The structure of the present invention is simple. By simply adding several mutually adhering copper sheets, the binding relationship between the drill pipe and the downhole parameter processing box is released, enabling the two to operate independently. And even if the number of signals to be transmitted increases significantly, this structure can be extremely conveniently expanded to meet the latest requirements.

[0021] 3. In actual projects where it is necessary to monitor the working status of the drill bit at similar times, the problem of wire winding has been plaguing for a long time. After adding a housing to this structure for an integrated detachable design, it can be used immediately after connection, which is very convenient and reliable, and has a wide application prospect. It is not only used on the drill pipe, but also applicable to the real-time acquisition and data processing of physical parameters of rotating moving parts.

[0022] 4. The present invention uses a disc as the stator and copper sheets as the rotors. During the rotation of the copper sheets driven by the drill pipe, signal transmission is achieved through the sliding contact between the stator and the rotors; setting the copper sheets between two discs and tightening them with springs ensures the stability of signal transmission; setting the discs and copper sheets into a multi-ring structure and a multi-zone structure respectively meets the simultaneous transmission of multiple signals; designing the detachable connection mode between the hollow connectors at the tail of the drill pipe is to achieve equipment integration on the premise of meeting more signal transmission work. In short, the present invention solves the problems of inaccurate and unstable measurement data caused by the high-speed co-rotation of the data processing box and the drill pipe during the working process of the measurement-while-drilling platform through a simple structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to illustrate the present invention more clearly, the drawings required for use in the following embodiments or the description of the prior art will be briefly introduced. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts.

[0024] Figure 1 It is a schematic diagram of the overall structure of the drill pipe carried by the existing measurement-while-drilling platform.

[0025] Figure 2 It is the front view of the embodiment of the non-co-rotating contact signal transmission structure of the present invention.

[0026] Figure 3 It is Figure 2 The sectional view taken along the A-A direction of, with the spring omitted in the figure.

[0027] Figure 4 It is the drill pipe carrying Figure 2 The schematic diagram of the overall structure of the drill pipe of the non-co-rotating contact signal transmission structure shown.

[0028] Figure 5 It is the schematic diagram of the overall structure of the drilling rig carrying the non-co-rotating contact signal transmission structure of the present invention.

[0029] In the figure: 1 - drill bit; 2 - threaded connection; 3 - drill pipe housing; 4 - strain gauge; 5 - wire; 6 - hollow drill pipe with length omitted; 7 - data processing box; 8 - trapezoidal input signal copper sheet; 9 - first insulating coating; 10 - signal receiving disc; 11 - spring; 10 - signal receiving disc; 12 - second insulating coating; 13 - base; 14 - power system; 15 - non - co - rotating contact signal transmission structure; 16 - fixed connecting rod; 17 - connecting piece, 18 - third insulating layer. Detailed implementation mode

[0030] The following combines the attached Figure 1 ~attached Figure 5 to elaborate in detail on the preferred embodiments of the present invention, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0031] Refer to Figure 1 Briefly describe the overall structure of the drill pipe carried by the existing measurement - while - drilling platform, so as to have a clearer understanding of the background technology. It can be seen from Figure 1 that the overall drill pipe includes the drill pipe housing 3, the hollow drill pipe 6, the drill bit 1 connected by the threaded connection 2, the data processing box 7 fixed on the drill pipe housing 3, and the strain gauge 4 attached to the hollow drill pipe 6. Since the data processing box 7 is fixed on the drill pipe housing 3, and the wire 5 of the strain gauge 4 passes through the center of the hollow drill pipe 6 and is connected to the data processing box 7, when the drill pipe rotates, it drives the data processing box 7 to rotate together. The data processing box 7 obtains the signal transmitted by the strain gauge 4 in real - time and processes it. During this process, the wire 5 will not get entangled during rotation. Just because of this, the data processing box 7 rotates continuously during drilling. The long - term rotation causes the sensitivity and stability of the precision components in the data processing box 7 to decrease, affecting the measurement accuracy of the parameters while drilling, and unable to provide an accurate basis for guiding the on - site excavation work, thus affecting the mining safety.

[0032] In order to solve Figure 1 the existing technical problems, the present invention designs Figure 2 the non - co - rotating contact signal transmission structure shown in Figure 2 which is just an embodiment and is for the case where two strain gauges are attached to the drill pipe. It should be noted that Figure 2 between the hollow disc and the strain gauge, and when the two groups of strain gauges are back - to - back during operation, they are in close contact. The state shown in the figure is non - contact for the convenience of understanding the drawing.

[0033] From Figure 2It can be seen that the embodiment of the non-rotary contact signal transmission structure of the present invention includes four trapezoidal input signal copper sheets 8, two hollow conductive signal receiving discs 10 and springs 11. The two signal receiving discs 10 are coaxially arranged. The four trapezoidal input signal copper sheets 8 are divided into two groups and are respectively attached back-to-back to the opposite surfaces of the two signal receiving discs 10. Springs 11 are provided on the opposite surfaces of the two signal receiving discs 10. Through the tension of the springs 11, both groups of trapezoidal input signal copper sheets 8 can be tightly attached to their respective signal receiving discs 10, ensuring that the trapezoidal input signal copper sheets 8 can continuously transmit signals while sliding; insulating paint is applied to the back-to-back parts of the two groups of trapezoidal input signal copper sheets 8, that is Figure 2 the first insulating layer 9 in

[0034] According to Figure 4 it can be seen that during use, the four trapezoidal input signal copper sheets 8 are connected to the connector 17 at the tail of the hollow drill rod 6, and then are electrically connected to the strain gauges 4 through the wires 5; the signal receiving discs 10 and the data processing box 7 are also electrically connected through wires.

[0035] According to Figure 3 it can be seen that the signal receiving disc 10 of the present invention is integrated by two inner and outer hollow discs. The outer ring part of the inner hollow disc and the inner ring part of the outer hollow disc are the contact parts of the two, and the contact parts are insulated, that is Figure 3 the third insulating layer 18 in Figure 3 The purpose of insulating the double-ring connection is to prevent signal interference and receive the signals conducted by different trapezoidal input signal copper sheets 8 and transmit them to the data processing box through wires. It can also be seen from the

[0036] cross-sectional result that a group of two trapezoidal input signal copper sheets 8 are attached to one signal receiving disc 10, and insulating paint is applied to the parts where the two trapezoidal input signal copper sheets 8 are in contact with the inner and outer hollow discs respectively, that is the third insulating layer 12 in the figure, which meets the requirement of simultaneous transmission of multiple groups of signals without mutual interference.

[0037] In order to weaken the influence of the wear of the insulating paint and the thickness of the insulating paint surface on the stable signal transmission, the thickness of the trapezoidal input signal copper sheet 8 can be appropriately increased, and the third insulating layer 12 of the trapezoidal input signal copper sheet 8 can be designed to be concave to reduce the contact area between the trapezoidal input signal copper sheet 8 and the signal receiving disc 10. In order to protect the transmission structure and facilitate disassembly, a detachable outer shell is added to the periphery of the trapezoidal input signal copper sheet 8 and the signal receiving disc 10. The setting method of the outer shell is a conventional technical means. For example, it can be set as an upper and lower snap-on outer shell, etc., which will not be elaborated here.

[0038] When the number of strain gauges at the front section of the hollow drill pipe 6 is large and the existing structure cannot meet the stable transmission of more signals without interference, the signal receiving disc 10 can be divided into a multi-ring structure, and the partition of the trapezoidal input signal copper sheet 8 is increased accordingly according to the number of rings. For example, the signal receiving disc 10 is divided into a three-ring structure, and the trapezoidal input signal copper sheet 8 is divided into three zones. According to the conductivity requirements, insulating paint is applied to different zones of the trapezoidal input signal copper sheet 8.

[0039] The following combines Figure 4 and Figure 5 to elaborate the application method of the non-co-rotating contact signal transmission structure of the present invention.

[0040] S1: Connect the non-co-rotating contact signal transmission structure to the tail of the hollow drill pipe 6. The connection method is: weld a hollow connector 17 at the center of the tail of the hollow drill pipe 6, and put the non-co-rotating contact signal transmission structure 15 on the hollow connector 17. Obviously, the inner diameter of the hollow connector 17 is smaller than the hollow diameter of the signal receiving disc 10, and the purpose is to ensure that the signal receiving disc 10 is fixed when the hollow drill pipe 6 rotates; the trapezoidal input signal copper sheet 8 is connected to the connector 17, the signal receiving disc 10 is fixed on the fixed connecting rod 16 of the bottom base 13 of the measurement platform while drilling, and the data processing box 7 is fixed on the bottom base 13; connect the wires between the signal receiving disc 10 and the data processing box 7 and between the trapezoidal input signal copper sheet 8 and the strain gauge 4;

[0041] When the number of strain gauges on the hollow drill hole 6 is large, a single non-co-rotating contact signal transmission structure 15 cannot meet the use requirements. At this time, a hollow connector (referred to as the second hollow connector) is connected to the tail of the hollow connector 17 through a thread, and a set of non-co-rotating contact signal transmission structure 15 is connected through the second hollow connector, and so on until the number of strain gauges is satisfied;

[0042] S2: After installation, first start the power system 14, and the hollow drill pipe 6 starts to rotate at a high speed. As the hollow drill pipe 6 advances forward, the drill bit 1 comes into contact with the rock to be measured. As the drill bit 1 continues to advance, the strain gauges 4 pasted on the rear end of the drill bit 1 are deformed to generate electrical signals, which are conducted backward along the wire 5 inside the hollow drill pipe 6 to the trapezoidal input signal copper sheet 8. The four trapezoidal input signal copper sheets 8 transmit the signals of different strain gauges 4 to the inner hollow disc or the outer hollow disc of the signal receiving disc 10, and then the inner hollow disc or the outer hollow disc of the signal receiving disc 10 transmits the signals to the data processing box 7. After being processed by the data processing box 7, the signals are transmitted to the computer in a wireless form for analysis work.

[0043] The above embodiment is an example of the present invention and does not limit the technical solution of the present invention. For example, the number of rings of the signal receiving disc 10 and the number of partitions of the trapezoidal input signal copper sheet 8 need to be determined according to the actual situation on site. However, no matter how many partitions the copper sheet has, only one partition of the copper sheet can be not coated with insulating paint, that is to say, each copper sheet can only be conducted with one disc. When the number of rings of the signal receiving disc 10 and the number of partitions of the trapezoidal input signal copper sheet 8 have reached the maximum, and at this time, the requirements of the strain gauges cannot be met, then a group of non-rotating contact signal transmission structures can be connected in parallel. This is also the main reason why the connecting parts of the present invention are set as threaded structures, which is to facilitate disassembly and installation.

Claims

1. A non-rotating contact signal transmission structure for measuring parameters while drilling, used to achieve signal transmission between the strain gauge at the front end of the drill pipe and the data processing box, characterized in that, The non-rotating contact signal transmission structure includes two conductive hollow discs and four copper sheets. The two hollow discs are fixed on the base at the tail of the drill pipe and are coaxial with the drill pipe. The four copper sheets are divided into two groups. The two groups of copper sheets are back-to-back and respectively attached to the opposite surfaces of the two hollow discs. The opposite surfaces of the two hollow discs are tightened by springs, so that the two groups of copper sheets are back-to-back and can be tightly attached to their respective hollow discs. The hollow discs are electrically connected to the data processing box. One end of the four copper sheets is connected to the tail of the drill pipe and is electrically connected to the strain gauges attached to the drill pipe. When the copper sheets rotate with the drill pipe, the hollow discs remain stationary. Insulating paint is applied to the back-to-back parts of the two groups of copper sheets. The hollow discs are formed by integrating multiple hollow discs with different diameters. The copper sheets are also divided into multiple zones. The number of zones of the copper sheets is the same as the number of hollow discs with different diameters. Each copper sheet is only not coated with insulating paint in one zone, ensuring that each copper sheet only transmits signals to one hollow disc and will not interfere with each other. The part of the copper sheet in contact with the hollow disc where the insulating paint is applied is made concave. The copper sheets are trapezoidal. The long side of the trapezoid is connected to the drill pipe, and the short side of the trapezoid is attached to the disc.

2. The non-rotating contact signal transmission structure for measuring parameters while drilling according to claim 1, wherein The hollow discs are formed by integrating an inner hollow disc and an outer hollow disc. The contact part between the inner and outer hollow discs is insulated. The copper sheets are also divided into two zones along with the discs. The area in contact with the inner hollow disc is called one zone, and the area in contact with the outer hollow disc is one zone. When the copper sheet needs to input a signal to the inner hollow disc, the zone of the copper sheet in contact with the outer hollow disc needs to be coated with insulating paint. Conversely, when the copper sheet needs to input a signal to the outer hollow disc, the area of the copper sheet in contact with the inner hollow disc needs to be coated with insulating paint. At the same time, one of the group of copper sheets attached to the same hollow disc must be insulated from the outer hollow disc and the other must be insulated from the inner hollow disc.

3. The non-rotating contact signal transmission structure for measuring parameters while drilling according to claim 1, characterized in that There are multiple groups of the non-rotating contact signal transmission structures, which are connected in parallel at the tail of the drill pipe in a detachable manner.

4. The non-rotating contact signal transmission structure for measuring parameters while drilling according to claim 1, characterized in that, The non-rotating contact signal transmission structure further includes a housing, which wraps the hollow discs and copper sheets.

5. An application method of the non-rotating contact signal transmission structure as claimed in claim 1 for measuring parameters while drilling, characterized in that, First, connect the non-rotating contact signal transmission structure to the drill pipe. The connection method is as follows: Fix a hollow connector coaxial with the drill pipe at the tail of the drill pipe. The hollow connector passes through the two hollow discs. The copper sheets are fixed on the hollow connector. The wires of the strain gauges attached to the front section of the drill pipe pass through the center of the drill pipe and the hollow connector and are connected to the copper sheets. When there are many strain gauges on the drill pipe and a single group of non-rotating contact signal transmission structures cannot meet the signal transmission requirements, thread-connect a second hollow connector to the tail of the connector, and connect the second group of non-rotating contact signal transmission structures to the drill pipe through the second hollow connector, and so on. Then start the drill pipe power system, and the drill pipe begins to rotate at high speed. As the drill pipe advances forward, the drill bit starts to contact the rock to be measured. With the continuous advancement of the drill bit, the strain gauges pasted on the rear end of the drill bit deform to generate electrical signals, which are conducted backward along the wires inside the hollow drill pipe to the contact transmission structure at the rear end. The signals are output from the contact transmission structure and directly transmitted to the data processing box through the wires. After being processed by the data processing box, they are transmitted to the computer in a wireless form for analysis.

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