A coal mine underground composite mud pulse while-drilling measurement system and method

Abstract

The application discloses a kind of coal mine underground composite mud pulse while drilling measurement system and method, including the short connection of rotary valve in turn, positive pulse short connection, drive short connection and circuit conversion connector, battery cylinder short connection and while drilling measurement short connection are connected in turn in the rear end of circuit conversion connector;Drive short connection can control the piston action in positive pulse short connection to control plugging or open conical flow passage to generate pressure positive pulse;While drilling measurement short connection acquisition module can acquire measurement parameter, while drilling measurement short connection main control module can control the work of servo motor in rotary valve short connection, to make the stator overflow passage and rotor overflow passage in rotary valve short connection periodic change occurs Area of overlap, form mud continuous pulse.The present application integrates positive pulse and continuous pulse generating device together, can realize positive pulse short connection, rotary valve short connection independent work, meet small data volume upload while meeting large data volume upload, positive pulse short connection, rotary valve short connection alternate work effectively reduce system power consumption.

Description

Technical Field

[0001] This invention belongs to the field of measurement while drilling technology, specifically relating to a composite mud pulse measurement while drilling system and method for coal mines. Background Technology

[0002] Directional drilling in coal mines is a crucial method and safety measure for gas control and extraction, water hazard prevention, geological structure exploration, and fire control. Measurement while drilling (MSD) systems are key equipment for achieving accurate and efficient directional drilling. With the improvement of coal mining levels, increasingly complex geological conditions, and the advancement of intelligent and transparent coal mine construction, higher demands are placed on the accuracy of borehole trajectory measurement, the diversity of drilling engineering parameter measurements, and the real-time nature of geological parameter measurements. Single trajectory parameter measurements are no longer sufficient to meet the requirements of intelligent and transparent coal mine construction.

[0003] Transparent working face construction, intelligent drilling, coal and rock strata identification, and geological anomaly identification are key aspects of intelligent coal mine construction. These require support from various parameters obtained through directional drilling, including borehole trajectory parameters (azimuth, dip angle, tool face), drilling engineering parameters (torque, drilling pressure, vibration, temperature, rotational speed, inner and outer annular pressure), and geological parameters (azimuth gamma, resistivity). Currently, underground drilling in coal mines primarily relies on wired measurement-while-drilling (MWD) and mud pulse MWD. ​​These methods mainly guide directional drilling by measuring borehole trajectory parameters (azimuth, dip angle, tool face). However, wired MWD systems suffer from poor long-distance signal transmission reliability and limited transmission distance, and also place high demands on drilling tools. While mud pulse generators overcome the problems of wired MWD systems, their transmission rates are low. With technological advancements, neither can meet the needs of large-volume data transmission. Continuous wave mud pulse MWD systems offer the advantage of high transmission speed, meeting the demands of large-volume data transmission, and are currently a focus of research and development. However, while continuous wave mud pulse measurement-while-drilling systems are relatively mature in the petroleum industry, they are still a blank in the field of coal mine drilling, with no related instruments, papers, or reports found. Due to the special characteristics of coal mine drilling, the size of the borehole and the "coal mine safety" requirements limit the possibility of using petroleum-related instruments in coal mines.

[0004] Furthermore, with the continuous integration of various types of measuring instruments, the types of parameters acquired are diverse. However, it is not necessary to upload all types of parameters simultaneously. Instead, the required parameter types are selected according to actual needs. Therefore, the uploading of multiple types of parameters is mainly done in an alternating (small data volume) or combined (large data volume) manner. In addition, mud pulse measurement while drilling systems generally adopt bottom hole power supply. Due to the limitations of drill string size and "coal mine safety" requirements, the battery capacity cannot be expanded indefinitely. Although mud positive pulse measurement while drilling systems have low power consumption and can achieve small data volume uploading, they cannot meet the requirements of large data volume uploading. Continuous pulse measurement while drilling systems can achieve both large and small data volume uploading, but they have the problem of high power consumption for small data volume uploading, which cannot guarantee the service life. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a composite mud pulse measurement while drilling system and method for coal mines, solving the aforementioned problems of data uploading and high power consumption.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A composite mud pulse measurement-while-drilling system for underground coal mines includes a rotary valve short circuit, a positive pulse short circuit, a drive short circuit, and a circuit conversion connector connected in sequence.

[0008] The rotary valve short circuit includes a rotary valve outer tube, and a circuit converter, a motor housing, a universal joint, a stator, and a rotor arranged in sequence inside the rotary valve outer tube; the motor housing is equipped with a servo motor, the stator is equipped with multiple stator overcurrent channels, and the rotor is equipped with multiple rotor overcurrent channels.

[0009] The positive pulse short circuit includes a positive pulse outer tube, and a piston outer sleeve, piston cylinder, piston outer tube, piston upper end cap, spring, piston, guide ring support, guide ring, and filter connector disposed inside the positive pulse outer tube; the front end of the filter connector is connected to the rotor, and the rear end of the filter connector is connected to the central flow channel of the guide ring, and the guide ring and guide ring support can form a conical flow channel; the front end of the piston is connected to the central flow channel of the guide ring, and the rear end of the piston extends into the piston cavity formed by the piston cylinder, piston outer tube, and piston upper end cap, and the rear end of the piston contacts the spring in the piston cavity;

[0010] The drive short circuit is equipped with a solenoid valve, which can control the piston movement in the positive pulse short circuit to control the blocking or opening of the conical flow channel, thereby controlling the generation of pressure positive pulses;

[0011] The rotary valve short circuit is sequentially connected to multiple drill pipes, water feeders, pressure transmitters, and a borehole explosion-proof computer. The circuit conversion connector is sequentially connected to a battery sleeve short circuit and a measurement-while-drilling (MSWD) short circuit. The MSWD short circuit includes an acquisition module and a main control module. The acquisition module can acquire borehole trajectory parameters, drilling engineering parameters, and geological parameters. The main control module can encode and modulate the acquired parameters and control the servo motor inside the rotary valve short circuit to periodically change the overlapping area of ​​the stator flow channel and the rotor flow channel by controlling the rotor rotation, thus forming continuous mud pulses. The main control module can also control the operation of the solenoid valve inside the short circuit to form positive mud pulses.

[0012] The present invention also includes the following technical features:

[0013] Specifically, the circuit converter includes an outer ring and an inner ring. The outer ring is fixed to the inner wall of the outer tube of the rotary valve. A wire bridge is connected between the inner ring and the outer ring. There is a fan-shaped flow channel between adjacent wire bridges. The front and rear ends of the inner ring are respectively equipped with end caps and a central connector. A second guide ring is sleeved on the outer ring. The second insulated wire in the wire bridge connects the second guide ring and the central connector.

[0014] Specifically, the motor housing includes a cylindrical motor protective shell and a servo motor inside; the outer wall of the motor protective shell is provided with multiple rectangular limiting blocks, and the ends of the rectangular limiting blocks are provided with limiting holes. The motor protective shell is limited to the inner wall of the outer tube of the rotary valve through the limiting holes and the fixing bolts inside; the servo motor has a built-in reducer, the servo motor is axially rigidly connected to the motor protective shell, the main shaft of the servo motor passes through the rear end of the motor protective shell and the main shaft is dynamically sealed to the rear end of the motor protective shell, the terminal of the servo motor is connected to the front end of the motor protective shell, and the front end of the terminal is mated with the center terminal.

[0015] The universal joint is connected to the spindle of the servo motor at the front end and to the front end of the rotor at the rear end, so as to stably transmit the power of the servo motor to the rotor.

[0016] Specifically, the stator has a disc-shaped structure and is fixed to the inner wall of the outer tube of the rotary valve by multiple positioning holes and bolts on its outer wall. The stator has a central through hole in the center, through which the rotor can pass. The stator has four stator flow channels evenly distributed in a 90° circle. The stator flow channels are fan-shaped and the contour of the stator flow channels near the flushing liquid inlet end is chamfered by 5mm to form a flow channel structure with a flow guiding function.

[0017] The rotor includes an outer ring of rotor bearing, bearing balls, and an inner disk of rotor bearing arranged from the outside to the inside. The inner disk of rotor bearing has multiple rotor flow channels. The center of the inner disk of rotor bearing is a drive shaft. The front end of the drive shaft is connected to a universal joint, and the rear end of the drive shaft has a central positioning hole.

[0018] Specifically, the rotary valve outer tube includes a rotary valve outer tube housing, a through hole is provided in the wall of the rotary valve outer tube housing, a third insulated wire is provided in the through hole, and the front and rear ends of the third insulated wire are respectively connected to a fourth guide ring and a third guide ring embedded in the inner wall of the rotary valve outer tube housing;

[0019] After the circuit converter is connected to the outer tube of the rotary valve, the second guide ring and the fourth guide ring are pressed together, thereby making the second insulated wire and the third insulated wire conductive.

[0020] Specifically, the filter connector has a hollow structure. The front end of the filter connector is provided with a positioning boss to insert and fit the central positioning hole, and the rear end is provided with a filter outlet. The side wall of the filter connector is provided with multiple filter holes, which can effectively filter solid particles with a diameter ≥1mm. The rinsing liquid flows in from the outer wall of the filter connector and flows out along the filter outlet. The rear end of the filter connector is connected to a guide ring.

[0021] Specifically, the guide ring is disposed on the stepped surface of the inner wall of the positive pulse outer tube and is pressed against the outer tube of the rotary valve. The guide ring has a central flow channel at its center, which is connected to the filter outlet of the filter connector. The front part of the guide ring is disc-shaped, and the rear part of the guide ring is a conical boss. The front part of the guide ring has a flow channel. The center of the guide ring support has a conical through hole. The rear end face of the front part of the guide ring presses against the front end face of the guide ring support, so that the rear part of the guide ring and the conical through hole of the guide ring support combine to form a conical flow channel, and the outlet of the conical flow channel is arc-shaped.

[0022] The rear end of the guide ring support consists of, in sequence, a piston outer sleeve, a piston, a piston upper end cap, a piston outer tube, a spring, and a piston cylinder. The front end of the piston passes through the piston outer sleeve and extends into the central flow channel of the guide ring. The rear end of the piston is located in the piston cavity and presses against the spring. Under normal conditions, the piston presses against the inner end face of the piston upper end cap. At this time, the piston head blocks the outlet of the conical flow channel. The piston has a hollow structure, allowing the flushing fluid to flow along the central flow channel through the piston and into the piston cavity. When the piston presses against the outer end face of the piston cylinder, the piston head fully opens the outlet of the conical flow channel.

[0023] Specifically, the piston cylinder body is a cylindrical structure, and the piston rod cylinder body is provided with evenly distributed positioning palms on its circumference. Each positioning palm is provided with bolt holes. The piston cylinder body is a piston cavity, and the rear end of the piston cylinder body is a drive shorting connection end. The drive shorting connection end is used to connect to the drive head of the internal instrument string of the drive shorting.

[0024] Specifically, the circuit adapter is a double-female structure, including a circuit adapter cylinder. Three wire-passing holes are evenly distributed in a 120° circle on one side of the outer wall of the circuit adapter cylinder. These holes connect the end face of the outer wall of the circuit adapter cylinder to the central through hole. Each wire-passing hole contains a first insulated wire. A first guide ring is provided on the end face of the outer wall of the circuit adapter cylinder, and the first guide ring is connected to the first insulated wire. An aviation plug is provided at one end of the central through hole, and a battery connector is provided at the other end. The first guide ring is connected to the battery connector via the first insulated wire, and the battery connector is connected to the aviation plug via the first insulated wire.

[0025] An industrial control method for a coal mine underground composite mud pulse measurement while drilling system includes the following steps: controlling the water injection pressure of the mud pump; when the pressure signal is greater than the set value K1 and less than K2, data acquisition is performed using mode one; when the pressure signal is greater than the set value K2, data acquisition is performed using mode two. Mode one measures borehole trajectory parameters, while mode two, in addition to acquiring borehole trajectory parameters, also acquires drilling engineering parameters and geological parameters. The specific parameter categories are determined according to the type of acquisition module integrated by the measurement while drilling short circuit.

[0026] Mode 1: The acquisition module collects drilling trajectory parameters, and the main control module controls the servo motor to control the rotor rotation. During the rotor rotation, the overlap area between the stator flow channel and the rotor flow channel changes, and ΔP is recorded. Max The position where the stator flow channel and the rotor flow channel overlap the most, and where the drive shaft of the brake servo motor is located, is the servo motor self-test and zero-adjustment process. At this time, the drive short-circuit internal solenoid valve sends a control signal, which drives the small valve head of the solenoid valve to move, thereby controlling the positive pulse short-circuit piston to move. According to a specific code, the conical flow channel formed by the combination of the guide ring and the guide ring support is blocked and opened, thereby generating a pressure positive pulse.

[0027] Mode 2: The acquisition module acquires drilling trajectory parameters and drilling engineering parameters and geological parameters at the same time. The main control module encodes and modulates the acquired data. At this time, the main control module also controls the servo motor to perform a self-check and zeroing process. Then, according to a specific code, the servo motor drives the rotor to rotate. The overlapping area of ​​the stator flow channel and the rotor flow channel changes periodically, forming continuous mud pulses.

[0028] Compared with the prior art, the present invention has the following technical effects:

[0029] The composite mud pulse measurement-while-drilling system of this invention integrates the positive pulse and continuous pulse generators together through sidewall wiring. It can achieve independent operation of positive pulse short-circuiting and rotary valve short-circuiting, satisfying both small and large data uploads. The alternating operation of positive pulse short-circuiting and rotary valve short-circuiting effectively reduces system power consumption.

[0030] The system of this invention is suitable for various downhole construction conditions. It can guide conventional directional drilling construction by uploading borehole trajectory parameters via positive pulses, and can also upload multiple types of parameters such as borehole trajectory parameters, drilling engineering parameters, and geological parameters via continuous pulses. It can effectively guide the construction of various types of directional boreholes, such as directional boreholes in the coal seam, water exploration and drainage holes, and geological anomaly exploration holes.

[0031] The system of this invention has two working modes, which are selected by controlling the water supply pressure, thereby realizing the switching of modes under different working conditions. The process is simple to operate. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the overall connection of the system of the present invention;

[0033] Figure 2 This is a cross-sectional view of the pulse generator assembly of the system of the present invention;

[0034] Figure 3 This is a front view of the pulse generator component circuit converter of the system of the present invention;

[0035] Figure 4 This is a sectional view of the pulse generator component circuit converter of the system of the present invention (BB).

[0036] Figure 5 This is a cross-sectional view of the pulse generator component AA of the system of the present invention;

[0037] Figure 6 This is a front view of the stator of the pulse generator assembly of the system of the present invention;

[0038] Figure 7 This is a CC cross-sectional view of the stator of the pulse generator assembly of the system of the present invention;

[0039] Figure 8 This is a front view of the rotor of the pulse generator assembly of the system of the present invention;

[0040] Figure 9 This is a cross-sectional view of the rotor DD of the pulse generator assembly of the system of the present invention;

[0041] Figure 10 This is a cross-sectional view of the outer pipe of the rotary valve short-circuit side wall of the system of the present invention;

[0042] Figure 11 This is a cross-sectional view of the filter connector of the pulse generator assembly in the system of the present invention;

[0043] Figure 12 This is a front view of the pulse generator assembly flow guide ring of the system of the present invention;

[0044] Figure 13This is a cross-sectional view of the pulse generator assembly guide ring EE of the system of the present invention;

[0045] Figure 14 This is a front view of the lower cylinder of the pulse generator assembly of the system of the present invention;

[0046] Figure 15 This is a cross-sectional view of the lower cylinder FF of the pulse generator assembly of the system of the present invention;

[0047] Figure 16 This is a cross-sectional view of the circuit conversion connector of the system of the present invention;

[0048] Figure 17 This is a flowchart of the system usage method of the present invention.

[0049] The meanings of the labels in the diagram are as follows:

[0050] 1. Rotary valve short-circuit, 2. Positive pulse short-circuit, 3. Drive short-circuit, 4. Circuit conversion connector;

[0051] 101. Circuit converter; 102. Motor housing; 103. Stator; 104. Rotor; 105. Rotary valve outer tube; 106. Universal joint;

[0052] 201. Filter connector, 202. Flow guide ring, 203. Flow guide ring support, 204. Piston, 205. Piston upper end cap, 206. Piston outer tube, 207. Piston cylinder, 208. Spring, 209. Piston outer sleeve, 210. Positive pulse outer tube;

[0053] 401. Circuit conversion connector cylinder body; 402. First insulated wire; 403. First guide ring; 404. Aviation plug; 405. Battery connector;

[0054] 1011. Center connector; 1012. Fan-shaped overcurrent channel; 1013. End cap; 1014. Second guide ring; 1015. Second insulated wire;

[0055] 1021. Motor protective housing; 1022. Fixing bolts;

[0056] 1031. Stator flow channel; 1032. Center through hole; 1033. Positioning hole;

[0057] 1041. Rotor bearing outer ring; 1042. Rotor bearing inner disc; 1043. Bearing ball; 1044. Rotor flow passage; 1045. Drive shaft; 1046. Center positioning hole; 1047. Retaining ring;

[0058] 1051. Rotary valve outer tube housing; 1052. Third guide ring; 1053. Fourth guide ring; 1054. Housing positioning hole; 1055. Third insulated wire;

[0059] 2011. Positioning boss; 2012. Filter hole; 2013. Filter outlet;

[0060] 2021. Flow guide ring flow channel; 2022. Conical boss; 2023. Central flow channel;

[0061] 2071. Positioning palm, 2072. Bolt hole, 2073. Piston cavity, 2074. Drive short-circuit connection end. Detailed Implementation

[0062] The following are specific embodiments of the present invention. It should be noted that the present invention is not limited to the following specific embodiments. All equivalent modifications made based on the technical solutions of this application fall within the protection scope of the present invention.

[0063] Example 1:

[0064] like Figures 1 to 16 As shown, this embodiment provides a coal mine underground composite mud pulse measurement while drilling system, including a rotary valve short circuit 1, a positive pulse short circuit 2, a drive short circuit 3, and a circuit conversion connector 4 connected in sequence.

[0065] The rotary valve short circuit 1 includes a rotary valve outer tube 105, and a circuit converter 101, a motor housing 102, a universal joint 106, a stator 103, and a rotor 104 arranged in sequence inside the rotary valve outer tube 105; a servo motor is provided inside the motor housing 102, multiple stator flow channels 1031 are provided on the stator 103, and multiple rotor flow channels 1044 are provided on the rotor 104.

[0066] The positive pulse short circuit 2 includes a positive pulse outer tube 210, and a piston outer sleeve 209, a piston cylinder 207, a piston outer tube 206, a piston upper end cap 205, a spring 208, a piston 204, a flow guide ring support 203, a flow guide ring 202, and a filter connector 201 disposed within the positive pulse outer tube 210. The front end of the filter connector 201 is connected to the rotor 104, and the rear end of the filter connector 201 is connected to the central flow passage 2023 of the flow guide ring 202. A conical flow channel can be formed between 202 and the guide ring support 203; the front end of the piston 204 is connected to the central flow channel 2023 of the guide ring 202, and the rear end of the piston 204 extends into the piston cavity 2073 formed by the piston cylinder 207, the piston outer tube 206 and the piston upper end cover 205. The rear end of the piston 204 contacts the spring 208 in the piston cavity 2073; the piston 204 can move axially back and forth, and the piston 204 can block or open the conical flow channel.

[0067] The drive short circuit 3 is equipped with a solenoid valve, which controls the piston 204 in the positive pulse short circuit 2 to block or open the conical flow channel between the guide ring 202 and the guide ring support 203, thereby controlling the generation of positive pressure pulses. Specifically, when the conical flow channel is open, the fluid flow pressure is a stable value; when the conical flow channel is closed, the pressure increases, and the pressure pulses generated by the alternating opening and closing of the conical flow channel are positive pulses.

[0068] When the pump is not running, the piston blocks the conical flow channel by the spring's thrust. When the pump is running and no pulse signal is sent, the piston moves to the right a certain distance due to the fluid pressure difference until the spring force and the valve head force are balanced. At this point, the conical flow channel opens to a certain area and then stops expanding. The drive short circuit is a standard product with an internal solenoid valve structure that extends or retracts the solenoid valve head according to specific coding rules. When the pump is running and a pulse signal is sent, the internal solenoid valve of the drive short circuit closes (i.e., the solenoid valve head extends). At this time, the sealed chamber at the lower end of the piston is no longer connected to the low-pressure area but is connected to the high-pressure area through the central hole. The lower end face of the piston is subjected to high pressure, causing the piston to move upward and reduce the area of ​​the conical flow channel, thereby increasing the system pressure. When the solenoid valve head opens the channel, the piston moves downward and the pressure returns to normal, thus generating a positive pulse.

[0069] After the mud pump is started, the liquid flows in and flows into the piston's internal channel along the conical flow channel and the filter joint. When no pulse is sent, the solenoid valve inside is in the open state (i.e., the solenoid valve head is retracted), which causes the lower end of the piston cavity to be a low-pressure area. The pressure at the upper end of the piston head is higher than that at the lower end, and the liquid flows into the conical flow channel, pushing the piston to the right to open the conical flow channel. The liquid flowing out of the conical flow channel flows through the annular gap between the piston cylinder and the positive pulse outer tube.

[0070] The front end of the rotary valve short circuit 1 is sequentially connected to multiple drill pipes, water feeders, pressure transmitters, and a borehole explosion-proof computer; the rear end of the circuit conversion connector 4 is sequentially connected to a battery sleeve short circuit and a measurement-while-drilling (MSWD) short circuit; the battery sleeve short circuit can power the composite mud pulse MSWD system; the MSWD short circuit includes an acquisition module and a main control module. The acquisition module can acquire borehole trajectory parameters, drilling engineering parameters, and geological parameters. The main control module can encode and modulate the acquired parameters and control the servo motor inside the rotary valve short circuit 1 to work, so as to control the rotor 104 to rotate and cause the overlapping area of ​​the stator flow channel 1031 and the rotor flow channel 1044 to change periodically, forming a continuous mud pulse; the main control module can also control the solenoid valve inside the drive short circuit 3 to act, forming a positive mud pulse.

[0071] The circuit converter 101 includes an outer ring and an inner ring. The outer ring is fixed to the inner wall of the outer tube 105 of the rotary valve. A wire bridge is connected between the inner ring and the outer ring. A fan-shaped flow channel 1012 is formed between adjacent wire bridges. The front and rear ends of the inner ring are respectively equipped with end caps 1013 and center connectors 1011. A second guide ring 1014 is sleeved on the outer ring. The second insulated wire 1015 in the wire bridge connects the second guide ring 1014 and the center connector 1011. Specifically, in this embodiment, both the outer ring and the inner ring are coaxial with the outer tube 105 of the rotary valve. The wire bridges are arranged radially along the outer ring, and the three wire bridges are evenly distributed circumferentially.

[0072] The motor housing 102 includes a cylindrical motor protective shell 1021 and a servo motor inside it; the outer wall of the motor protective shell 1021 is provided with a plurality of rectangular limiting blocks, and the ends of the rectangular limiting blocks are provided with limiting holes. The motor protective shell 1021 is limited to the inner wall of the rotary valve outer tube 105 through the limiting holes and the fixing bolts 1022 inside it; in this embodiment, there are three rectangular limiting blocks and they are evenly distributed along the circumference of the outer wall of the motor protective shell 1021; the servo motor has a built-in reducer, and the servo motor is axially rigidly connected to the motor protective shell 1021. The main shaft of the servo motor passes through the rear end of the motor protective shell 1021 and the main shaft is dynamically sealed to the rear end of the motor protective shell 1021. The terminal of the servo motor is connected to the front end of the motor protective shell 1021, and the front end of the terminal is mated with the center terminal 1011; the front end of the universal joint 106 is connected to the main shaft of the servo motor, and the rear end is connected to the front end of the rotor 104 to stably transmit the power of the servo motor to the rotor 104.

[0073] The stator 103 has a disc-shaped structure and is fixed to the inner wall of the rotary valve outer tube 105 by multiple positioning holes 1033 on its outer wall and bolts. In this embodiment, there are three positioning holes 1033, which are evenly distributed around the circumference of the outer wall of the stator 103. The stator 103 has a central through hole 1032, through which the rotor 104 can pass. The stator 103 has four stator flow channels 1031 evenly distributed around the circumference at 90°. The stator flow channels 1031 are fan-shaped. The stator flow channels 1031 have a 5mm chamfer near the flushing liquid inflow end to form a flow channel structure with a flow guiding function.

[0074] The rotor 104 includes a rotor bearing outer ring 1041, bearing balls 1043, and rotor bearing inner disk 1042 arranged from the outside to the inside. The rotor bearing inner disk 1042 has multiple rotor flow channels 1044. A drive shaft 1045 is located at the center of the rotor bearing inner disk 1042. The front end of the drive shaft 1045 is connected to a universal joint 106, and the rear end of the drive shaft 1045 has a central positioning hole 1046. The drive shaft 1045 is mechanically connected to the universal joint 106, and the distance between the rotor 104 and the stator 103 is controlled by adjusting the connection depth between the universal joint 106 and the drive shaft 1045. The adjustable distance range is controlled within 2-5 mm, thereby controlling the pressure pulse amplitude. After the rotor bearing outer ring 1041, bearing balls 1043, and rotor bearing inner disk 1042 are assembled, a retaining ring 1047 is welded to the end face of the rotor bearing outer ring 1041 on the side where the flushing fluid flows in. Its main function is to prevent the flushing fluid from depressurizing along the gaps between the bearing balls 1043. The central positioning hole 1046 is connected to the filter connector 201 on the upper part of the positive pulse short circuit 2. The filter connector 201 provides radial support for the rotor 104. The bearing structure outside the rotor 104 provides radial limiting and also ensures that the rotor 1044 rotates smoothly.

[0075] The rotary valve outer tube 105 includes a rotary valve outer tube housing 1051. A through-hole is provided inside the wall of the rotary valve outer tube housing 1051, and a third insulated wire 1055 is installed inside the through-hole. The front and rear ends of the third insulated wire 1055 are respectively connected to a fourth guide ring 1053 and a third guide ring 1052 embedded in the inner wall of the rotary valve outer tube housing 1051. Specifically, the rotary valve outer tube 105 adopts a sidewall wiring structure, and three circumferentially distributed circumferentially arranged 120° loops are provided on the inner wall of the rotary valve outer tube housing 1051. The through-hole is equipped with a third insulated wire 1055, and the two ends of the third insulated wire 1055 are respectively connected to the third guide ring 1052 and the fourth guide ring 1053; the side wall of the outer tube housing 1051 of the rotary valve has two sets of housing positioning holes 1054, each set of three housing positioning holes 1054 and evenly distributed in a 120° circle. One set of housing positioning holes 1054 is used to limit and fix the motor protective housing 1021, and the other set of housing positioning holes 1054 is used to limit and fix the stator 103.

[0076] After the circuit converter 101 is connected to the rotary valve outer tube 105, the second guide ring 1014 and the fourth guide ring 1053 are pressed together, thereby making the second insulated wire 1015 and the third insulated wire 1055 conductive, which can then be used to power the motor. Similarly, the positive pulse outer tube 210 and the drive shorting 3 outer tube both adopt the same wiring principle. Through the cooperation between the outer tubes, the end faces of their respective guide rings are pressed together to make the circuit conductive.

[0077] The filter connector 201 has a hollow structure. The front end of the filter connector 201 is provided with a positioning boss 2011 to be inserted into the center positioning hole 1046, and the rear end is provided with a filter outlet 2013. The side wall of the filter connector 201 is provided with multiple filter holes 2012, which can effectively filter solid particles with a diameter ≥1mm. The rinsing liquid flows in from the outer wall of the filter connector 201 and flows out along the filter outlet 2013. The rear end of the filter connector 201 is connected to a guide ring 202.

[0078] The guide ring 202 is located on the stepped surface of the inner wall of the positive pulse outer tube 210 and is pressed against the outer tube 105 of the rotary valve. The guide ring 202 has a central flow channel 2023 at its center, which is connected to the filter outlet 2013 of the filter connector 201. The front part of the guide ring 202 is disc-shaped, and the rear part of the guide ring 202 is a conical boss 2022. The front part of the guide ring 202 has three guide ring flow channels 2021 evenly distributed in a 120° circle. The guide ring support 203 has a conical through hole at its center. The rear end face of the front part of the guide ring 202 presses against the front end face of the guide ring support 203, so that the rear part of the guide ring 202 and the conical through hole of the guide ring support 203 combine to form a conical flow channel, and the outlet of the conical flow channel is arc-shaped.

[0079] The rear end of the guide ring support 203 consists of, in sequence, a piston outer sleeve 209, a piston 204, a piston upper end cap 205, a piston outer tube 206, a spring 208, and a piston cylinder 207. The front end of the piston 204 passes through the piston outer sleeve 209 and extends into the central flow channel 2023 of the guide ring 202. The rear end of the piston 204 is located in the piston cavity 2073 and abuts against the spring 208. Under normal conditions, the piston 204 presses against the inner end face of the piston upper end cap 205. At this time, the piston 204... The piston 204 head blocks the outlet of the conical flow channel. The piston 204 has a hollow structure, allowing the flushing liquid to flow through the central flow channel 2023 and into the piston cavity 2073. The piston 204 can move freely in the cavity for a certain distance, which is the distance between the inner end face of the piston upper end cover 205 and the outer end face of the piston cylinder 207. When the piston 204 reaches the outer end face of the piston cylinder 207, the piston head of the piston 204 fully opens the outlet of the conical flow channel.

[0080] The piston cylinder 207 has a cylindrical structure. The piston 204 has three positioning palms 2071 evenly distributed in a 120° circle around the cylinder. Each positioning palm 2071 has a bolt hole 2072. The piston cylinder 207 contains a piston cavity 2073. The rear of the piston cylinder 207 is a drive shorting connection end 2074, which is used to connect to the drive head of the instrument string inside the drive shorting 3.

[0081] The circuit conversion connector 4 is a double-female structure. Its function is to transform the side wall wiring structure into a center wiring structure, thereby connecting to the rear battery tube and shorting the built-in battery tube, so that it can supply power to the internal solenoid valve and rotary valve of the upper drive shorting 1 and the internal servo motor. The circuit conversion connector 4 includes a circuit conversion connector cylinder 401. The outer wall of the circuit conversion connector cylinder 401 has three wiring holes evenly distributed in a 120° circle. The wiring holes connect the end face of the outer wall of the circuit conversion connector cylinder 401 and the center through hole 1032. Each wiring hole is provided with a first insulated wire 402. The end face of the outer wall of the circuit conversion connector cylinder 401 is provided with a first guide ring 403. The first guide ring 403 is connected to the first insulated wire 402. One end of the center through hole 1032 is provided with an aviation plug 404. The other end of the center through hole 1032 is provided with a battery connector 405. The first guide ring 403 is connected to the battery connector 405 through the first insulated wire 402. The battery connector 405 is connected to the aviation plug 404 through the first insulated wire 402.

[0082] The first guide ring 403, the second guide ring 1014, the third guide ring 1052, and other guide rings involved in the tube body that come into contact with the tube body are all insulated. Insulating adhesive can be applied to the insulating surface during the installation of the guide rings.

[0083] Example 2:

[0084] This embodiment provides an industrial control method for the coal mine downhole composite mud pulse measurement-while-drilling system of claim 1, such as... Figure 17 As shown, the measurement while drilling (MWD) connection is not limited to the acquisition of borehole trajectory parameters, but can also include the acquisition of drilling engineering parameters (temperature, rotational speed, vibration, drill string internal pressure, drill string external pressure, torque, drilling pressure, etc.) and geological parameters (gamma value, resistivity, etc.). Given the above-mentioned multiple types of data acquisition conditions, in order to achieve the alternating acquisition of different types and quantities of parameters during the same borehole construction, the specific steps are as follows: Control the mud pump water injection pressure value. When the pressure signal acquired by the pressure sensor inside the main control module is greater than the set value K1 and less than K2, the main control board uses mode one for data acquisition. When the pressure signal acquired by the pressure sensor inside the main control module is greater than the set value K2, the main control board uses mode two for data acquisition. Mode one measures borehole trajectory parameters (azimuth, dip angle, tool face), while mode two, in addition to acquiring borehole trajectory parameters, also acquires drilling engineering parameters and geological parameters. The specific parameter categories are determined according to the type of acquisition module integrated in the MWD connection.

[0085] Specifically, the following modes are included:

[0086] Mode 1: The acquisition module collects drilling trajectory parameters (azimuth, inclination, tool face). The main control module encodes and modulates the collected data. At this time, the main control module first sends a control signal to the motor drive module to drive the servo motor. The servo motor controls the rotor rotation. During rotor rotation, the overlap area between the stator flow channel and the rotor flow channel changes. The motor drive module records ΔP. Max The maximum position (i.e., the position where the stator flow channel and the rotor flow channel overlap the most) and the brake servo motor drive shaft is in this position. This process is the servo motor self-test and zeroing process. At this time, the control module sends a control signal to the drive short-circuit internal solenoid valve, which drives the small valve head of the solenoid valve to move, thereby controlling the positive pulse short-circuit piston to move. According to a specific code, the conical flow channel formed by the combination of the conical surface of the guide ring and the conical surface of the guide ring support is blocked and opened, thereby generating a pressure positive pulse.

[0087] Mode 2: The acquisition module acquires drilling trajectory parameters (azimuth, inclination, tool face) while simultaneously acquiring drilling engineering parameters (temperature, rotation speed, vibration, drill string internal pressure, drill string external pressure, torque, drilling pressure, etc.) and geological parameters (gamma value, resistivity, etc.). The main control module encodes and modulates the acquired data. At this time, the main control module also sends control signals to the motor drive module to drive the servo motor to perform a self-check and zeroing process. Then, according to a specific code, the servo motor drives the rotor to rotate. The overlapping area of ​​the stator flow channel and the rotor flow channel changes periodically, forming continuous mud pulses.

Claims

1. A composite mud pulse measurement-while-drilling system for coal mines, characterized in that, It includes a rotary valve short circuit (1), a positive pulse short circuit (2), a drive short circuit (3), and a circuit conversion connector (4) connected in sequence. The rotary valve short circuit (1) includes a rotary valve outer tube (105), and a circuit converter (101), a motor housing (102), a universal joint (106), a stator (103), and a rotor (104) arranged in sequence inside the rotary valve outer tube (105); a servo motor is provided inside the motor housing (102), multiple stator flow channels (1031) are provided on the stator (103), and multiple rotor flow channels (1044) are provided on the rotor (104); The positive pulse short circuit (2) includes a positive pulse outer tube (210), and a piston outer sleeve (209), a piston cylinder (207), a piston outer tube (206), a piston upper end cap (205), a spring (208), a piston (204), a flow guide ring support (203), a flow guide ring (202), and a filter connector (201) disposed inside the positive pulse outer tube (210); the front end of the filter connector (201) is connected to the rotor (104), and the rear end of the filter connector (201) is connected to the flow guide ring (202). 2) The central flow channel (2023) is connected, and the guide ring (202) and the guide ring support (203) can form a conical flow channel; the front end of the piston (204) is connected to the central flow channel (2023) of the guide ring (202), and the rear end of the piston (204) is inserted into the piston cavity (2073) formed by the piston cylinder (207), the piston outer tube (206) and the piston upper end cover (205). The rear end of the piston (204) contacts the spring (208) in the piston cavity (2073); The drive short circuit (3) is equipped with a solenoid valve, which can control the piston (204) in the positive pulse short circuit (2) to control the blocking or opening of the conical flow channel, thereby controlling the generation of pressure positive pulse; The front end of the rotary valve short circuit (1) is connected in sequence to multiple drill rods, water feeders, pressure transmitters, and orifice explosion-proof computers; the rear end of the circuit conversion connector (4) is connected in sequence to battery sleeve short circuit and measurement while drilling short circuit; the measurement while drilling short circuit includes a data acquisition module and a main control module. The data acquisition module can acquire borehole trajectory parameters, drilling engineering parameters, and geological parameters. The main control module can encode and modulate the acquired parameters and control the servo motor inside the rotary valve short circuit (1) to work, so as to make the overlapping area of ​​the stator flow channel (1031) and the rotor flow channel (1044) change periodically by controlling the rotor (104) to form a continuous mud pulse; the main control module can also control the solenoid valve inside the drive short circuit (3) to act, forming a positive mud pulse.

2. The coal mine downhole composite mud pulse MWD system of claim 1, wherein, The circuit converter (101) includes an outer ring and an inner ring. The outer ring is fixed to the inner wall of the outer tube (105) of the rotary valve. A wire bridge is connected between the inner ring and the outer ring. A fan-shaped flow channel (1012) is formed between adjacent wire bridges. End caps (1013) and a center connector (1011) are installed at the front and rear ends of the inner ring, respectively. A second guide ring (1014) is sleeved on the outer ring. The second insulated wire (1015) in the wire bridge connects the second guide ring (1014) and the center connector (1011).

3. The coal mine downhole composite mud pulse MWD system of claim 2, wherein, The motor housing (102) includes a cylindrical motor protective shell (1021) and a servo motor inside it; the outer wall of the motor protective shell (1021) is provided with multiple rectangular limiting blocks, and the ends of the rectangular limiting blocks are provided with limiting holes. The motor protective shell (1021) is limited to the inner wall of the rotary valve outer tube (105) through the limiting holes and the fixing bolts (1022) inside it; the servo motor has a built-in reducer, the servo motor and the motor protective shell (1021) are axially hard-connected, the main shaft of the servo motor passes through the rear end of the motor protective shell (1021) and the main shaft is dynamically sealed to the rear end of the motor protective shell (1021), the terminal of the servo motor is connected to the front end of the motor protective shell (1021), and the front end of the terminal is mated with the center terminal (1011); The universal joint (106) is connected to the spindle of the servo motor at the front end and to the front end of the rotor (104) at the rear end, so as to stably transmit the power of the servo motor to the rotor (104).

4. The coal mine downhole composite mud pulse MWD system of claim 1, wherein, The stator (103) is a disc-shaped structure. The stator (103) is fixed to the inner wall of the outer tube (105) of the rotary valve through multiple positioning holes (1033) on its outer wall and bolts. The stator (103) has a central through hole (1032) in the center, through which the rotor (104) can pass. The stator (103) has four stator flow channels (1031) evenly distributed in a 90° circle. The stator flow channels (1031) are fan-shaped. The stator flow channels (1031) have a 5mm chamfer on the contour of the flushing liquid inlet end, so as to form a flow channel structure with a flow guiding function. The rotor (104) includes a rotor bearing outer ring (1041), bearing balls (1043) and rotor bearing inner disk (1042) arranged from the outside to the inside. The rotor bearing inner disk (1042) is provided with multiple rotor flow channels (1044). The center of the rotor bearing inner disk (1042) is a drive shaft (1045). The front end of the drive shaft (1045) is connected to a universal joint (106), and the rear end of the drive shaft (1045) is provided with a central positioning hole (1046).

5. The coal mine downhole composite mud pulse MWD system of claim 2, wherein, The rotary valve outer tube (105) includes a rotary valve outer tube housing (1051). A through hole is provided in the wall of the rotary valve outer tube housing (1051). A third insulated wire (1055) is provided in the through hole. The front and rear ends of the third insulated wire (1055) are respectively connected to a fourth guide ring (1053) and a third guide ring (1052) embedded in the inner wall of the rotary valve outer tube housing (1051). After the circuit converter (101) is connected to the outer tube (105) of the rotary valve, the second guide ring (1014) and the fourth guide ring (1053) are pressed together, thereby making the second insulated wire (1015) and the third insulated wire (1055) conductive.

6. The coal mine downhole composite mud pulse MWD system of claim 4, wherein, The filter connector (201) has a hollow structure. The front end of the filter connector (201) is provided with a positioning boss (2011) to mate with the central positioning hole (1046). The rear end is provided with a filter outlet (2013). The side wall of the filter connector (201) is provided with multiple filter holes (2012), which can effectively filter water of various diameters. 1mm solid particles, the flushing liquid flows in from the outer wall of the filter connector (201) and flows out along the filter outlet (2013); the rear end of the filter connector (201) is connected to the guide ring (202).

7. The coal mine downhole composite mud pulse MWD system of claim 1, wherein, The guide ring (202) is located on the stepped surface of the inner wall of the positive pulse outer tube (210) and is pressed against the outer tube of the rotary valve (105). The guide ring (202) has a central flow channel (2023) at its center, which is connected to the filter outlet (2013) of the filter connector (201). The front part of the guide ring (202) is disc-shaped, and the rear part of the guide ring (202) is a conical boss (2022). The front part of the guide ring (202) has a guide ring flow channel (2021). The guide ring support (203) has a conical through hole at its center. The rear end face of the front part of the guide ring (202) presses against the front end face of the guide ring support (203), so that the rear part of the guide ring (202) and the conical through hole of the guide ring support (203) combine to form a conical flow channel, and the outlet of the conical flow channel is arc-shaped. The rear end of the flow guide ring support (203) consists of, in sequence, a piston outer sleeve (209), a piston (204), a piston upper end cap (205), a piston outer tube (206), a spring (208), and a piston cylinder (207); the front end of the piston (204) passes through the piston outer sleeve (209) and extends into the central flow channel (2023) of the flow guide ring (202); the rear end of the piston (204) is located in the piston cavity (2073) and presses against the spring (208); under normal conditions... When the piston (204) presses against the inner end face of the piston upper end cap (205), the piston head (204) of the piston (204) blocks the outlet of the conical flow channel. The piston (204) is a hollow structure, which allows the flushing liquid to flow through the piston (204) along the central flow channel (2023) and enter the piston cavity (2073). When the piston (204) reaches the outer end face of the piston cylinder (207), the piston head (204) of the piston (204) fully opens the outlet of the conical flow channel.

8. The coal mine downhole composite mud pulse MWD system of claim 1, wherein, The piston cylinder (207) is a cylindrical structure. The piston (204) rod cylinder is provided with evenly distributed positioning palms (2071) around its circumference. Each positioning palm (2071) is provided with bolt holes (2072). The piston cylinder (207) contains a piston cavity (2073). The tail of the piston cylinder (207) is a drive short-circuit connection end (2074). The drive short-circuit connection end (2074) is used to connect to the drive head of the instrument string inside the drive short-circuit (3).

9. The coal mine downhole composite mud pulse MWD system of claim 1, wherein, The circuit conversion connector (4) is a double-female structure, including a circuit conversion connector cylinder (401). Three wire holes are evenly distributed in a 120° circle on one side of the outer wall of the circuit conversion connector cylinder (401). The wire holes connect the end face of the outer wall of one side of the circuit conversion connector cylinder (401) and the central through hole (1032). Each wire hole is provided with a first insulated wire (402). A first guide ring (403) is provided on the end face of the outer wall of one side of the circuit conversion connector cylinder (401). The first guide ring (403) is connected to the first insulated wire (402). An aviation plug (404) is provided at one end of the central through hole (1032). A battery connector (405) is provided at the other end of the central through hole (1032). The first guide ring (403) is connected to the battery connector (405) through the first insulated wire (402). The battery connector (405) is connected to the aviation plug (404) through the first insulated wire (402).

10. The industrial control method of the coal mine underground composite mud pulse MWD system according to claim 1, characterized in that, The steps are as follows: Control the water injection pressure of the mud pump. When the pressure signal is greater than the set value K1 and less than K2, use mode one for data acquisition. When the pressure signal is greater than the set value K2, use mode two for data acquisition. Mode one measures the borehole trajectory parameters. Mode two measures the drilling engineering parameters and geological parameters in addition to the borehole trajectory parameters. The specific parameter categories are determined according to the type of acquisition module integrated by the measurement while drilling. Mode 1: The acquisition module collects drilling trajectory parameters, and the main control module controls the servo motor to control the rotor rotation. During the rotor rotation, the overlap area between the stator flow channel and the rotor flow channel changes, and ΔP is recorded. Max The position where the stator flow channel and the rotor flow channel overlap the most, and where the drive shaft of the brake servo motor is located, is the servo motor self-test and zero-adjustment process. At this time, the drive short-circuit internal solenoid valve sends a control signal, which drives the small valve head of the solenoid valve to move, thereby controlling the positive pulse short-circuit piston to move. According to a specific code, the conical flow channel formed by the combination of the guide ring and the guide ring support is blocked and opened, thereby generating a pressure positive pulse. Mode 2: The acquisition module acquires drilling trajectory parameters and drilling engineering parameters and geological parameters at the same time. The main control module encodes and modulates the acquired data. At this time, the main control module also controls the servo motor to perform a self-check and zeroing process. Then, according to a specific code, the servo motor drives the rotor to rotate. The overlapping area of ​​the stator flow channel and the rotor flow channel changes periodically, forming continuous mud pulses.

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