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

Abstract

A coal-mine underground composite mud pulse measurement while drilling system and a method. The system comprises a rotary valve sub (1), a positive pulse sub (2), a drive sub (3), and a circuit conversion adapter (4) which are connected in sequence, wherein the rear end of the circuit conversion adapter (4) is sequentially connected to a battery cylinder sub and a measurement while drilling sub; the drive sub (3) can control a piston (204) in the positive pulse sub (2) to act so as to control blocking or opening of a conical flow channel to generate a positive pressure pulse; a measurement while drilling sub acquisition module can acquire a measurement parameter, and a measurement while drilling sub master control module can control working of a servo motor in the rotary valve sub (1), so that the overlapping area between stator flow passing channels (1031) and rotor flow passing channels (1044) in the rotating valve sub (1) changes periodically to form mud continuous pulses.

Description

A composite mud pulse measurement while drilling system and method for underground coal mines Technical Field

[0001] The invention belongs to the technical field of measurement while drilling, and in particular relates to a composite mud pulse measurement while drilling system and method for underground coal mines. Background Art

[0002] Directional drilling in underground coal mines is an important method and safety measure for gas control and extraction, flood prevention, geological structure exploration, and fire control. Measurement while drilling (MWD) systems are key equipment for accurate and efficient directional drilling. With the improvement of coal mining standards, the increasing complexity of geological conditions, and the advancement of intelligent and transparent coal mine construction, higher requirements are being placed on the accuracy of borehole trajectory measurement, the diversity of drilling engineering parameter measurements, and the real-time performance of geological parameter measurements. Single trajectory parameter measurement can no longer 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 components of intelligent coal mine development. These require the support of a variety of parameters, including borehole trajectory parameters (azimuth, inclination, tool face), drilling parameters (torque, weight on bit, vibration, temperature, rotational speed, internal and external annular pressure), and geological parameters (azimuth gamma, resistivity), acquired through directional drilling. Currently, wired MWD and mud positive pulse MWD systems are predominant in underground coal mine drilling operations. These systems primarily measure borehole trajectory parameters (azimuth, inclination, tool face) to guide directional drilling operations. However, wired MWD systems suffer from poor signal reliability over long distances, limited transmission distances, and high requirements for drilling tools. While mud positive pulse generators overcome the challenges of wired MWD systems, their transmission rates are relatively low. With technological advancements, neither system can meet the needs of large-scale data transmission. Continuous-wave mud pulse MWD systems offer the advantage of high transmission speeds, meeting these data transmission requirements, and are currently a key research and development focus. While continuous-wave mud pulse measurement-while-drilling systems are relatively mature in the petroleum industry, they are still relatively new to underground coal mine drilling, with no relevant instruments, papers, or reports. Due to the unique characteristics of underground coal mine drilling, aperture size, and coal safety requirements, the use of petroleum-based instruments in coal mines is limited.

[0004] And with the continuous integration of various types of measuring instruments, the types of parameters obtained are diverse, but it is not necessary to upload all types of parameters at the same time. Instead, the required parameter types are selected according to actual needs. Therefore, multi-type parameter uploads are mainly uploaded in alternating (small data volume) or combined (large data volume) ways. In addition, the mud pulse downhole measurement system generally adopts the bottom hole power supply form. Due to the limitations of drill tool size and "coal safety" requirements, the battery capacity cannot be expanded indefinitely. Although the mud positive pulse downhole measurement system has low power consumption and can realize small data volume upload, it cannot meet the needs of large data volume upload; the continuous pulse downhole measurement system can realize large and small data volume upload, but there is a problem of high power consumption when uploading small data volume, and the service life cannot be guaranteed.

[0005] Summary of the Invention

[0006] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a composite mud pulse measurement while drilling system and method for underground coal mines to solve the above-mentioned problems such as data uploading and high power consumption.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0008] A composite mud pulse measurement while drilling system for underground coal mines, comprising a rotary valve short circuit, a positive pulse short circuit, a drive short circuit and a circuit conversion joint connected in sequence;

[0009] 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 the rotary valve outer tube and connected in sequence; a servo motor is arranged in the motor housing, a plurality of stator flow passages are arranged on the stator, and a plurality of rotor flow passages are arranged on the rotor;

[0010] The positive pulse short circuit includes a positive pulse outer tube, and a piston sleeve, a piston cylinder, a piston outer tube, a piston upper end cover, a spring, a piston, a guide ring support, a guide ring and a filter joint arranged in the positive pulse outer tube; the front end of the filter joint is connected to the rotor, the rear end of the filter joint is connected to the central flow channel of the guide ring, and a conical flow channel can be formed between the guide ring and the guide ring support; the front end of the piston is connected to the central flow channel of the guide ring, the rear end of the piston penetrates into the piston cavity surrounded by the piston cylinder, the piston outer tube and the piston upper end cover, and the rear end of the piston contacts the spring in the piston cavity;

[0011] The driving short circuit is provided with a solenoid valve, which can control the piston action in the positive pulse short circuit to control the blocking or opening of the tapered flow channel, thereby controlling the generation of the pressure positive pulse;

[0012] The front end of the rotary valve short circuit is connected in sequence to multiple drill pipes, water feeders, pressure transmitters, and orifice explosion-proof computers; the rear end of the circuit conversion joint is connected in sequence to the battery tube short circuit and the measurement while drilling short circuit; the measurement while drilling short circuit includes an acquisition module and a main control module. The acquisition module can acquire drilling trajectory parameters, drilling engineering parameters, and geological parameters. The main control module can encode and modulate the acquired parameters and control the operation of the servo motor in the rotary valve short circuit, so as to control the rotation of the rotor to cause the overlapping area of ​​the stator flow channel and the rotor flow channel to change periodically, thereby forming a continuous mud pulse; the main control module can also control the action of the electromagnetic valve inside the drive short circuit to form a positive mud pulse.

[0013] The present invention also includes the following technical features:

[0014] 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 covers and a central aviation plug. A second guide ring is sleeved on the outer ring, and the second insulated wire in the wire bridge connects the second guide ring and the central aviation plug.

[0015] Specifically, the motor housing includes a cylindrical motor protection shell and a servo motor therein; a plurality of rectangular limit blocks are provided on the outer wall of the motor protection shell, and a limit hole is provided at the end of the rectangular limit block, and the motor protection shell is limited to the inner wall of the outer tube of the rotary valve through the limit hole and the fixing bolts therein; the servo motor has a built-in reducer, the servo motor and the motor protection shell are axially hard-linked, the main shaft of the servo motor passes through the rear end of the motor protection shell and the main shaft and the rear end of the motor protection shell are dynamically sealed, the servo motor terminal is connected to the front end aviation plug of the motor protection shell, and the front end aviation plug is matched with the center aviation plug;

[0016] The front end of the universal joint is connected to the main shaft of the servo motor, and the rear end is connected to the front end of the rotor, so as to stably transmit the power of the servo motor to the rotor.

[0017] Specifically, the stator is a disc-shaped structure, and is fixed to the inner wall of the outer tube of the rotary valve through multiple positioning holes and bolts on its outer wall; a central through hole is provided in the center of the stator, and the rotor can pass through the central through hole. The stator is provided with four stator flow channels evenly distributed at 90 degrees around the circumference. The stator flow channels are fan-shaped, and the contour of the stator flow channel near the inlet end of the flushing liquid is chamfered by 5mm to form a guide groove structure with a diversion function;

[0018] The rotor includes a rotor bearing outer ring, bearing balls and a rotor bearing inner disk arranged from the outside to the inside. The rotor bearing inner disk is provided with multiple rotor flow channels; the center of the rotor bearing inner disk is a transmission shaft, the front end of the transmission shaft is connected to the universal shaft, and the rear end of the transmission shaft is provided with a center positioning hole.

[0019] Specifically, the rotary valve outer tube includes a rotary valve outer tube shell, a wire hole is provided in the wall of the rotary valve outer tube shell, a third insulated wire is provided in the wire 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 shell;

[0020] After the circuit converter is matched with the outer tube of the rotary valve, the second guide ring and the fourth guide ring are pressed tightly, thereby making the second insulated wire and the third insulated wire conductive.

[0021] Specifically, the filter joint is a hollow structure, with a positioning boss provided at the front end of the filter joint to be plugged into the central positioning hole, a filter outlet provided at the rear end, and a plurality of filter holes provided on the side wall of the filter joint, which can effectively filter solid particles with a diameter of ≥1mm. The flushing liquid flows into the outer wall of the filter joint and flows out along the filter outlet; the rear end of the filter joint is connected to a guide ring;

[0022] Specifically, the guide ring is arranged on the stepped surface of the inner wall of the positive pulse outer tube and is tightened by the outer tube of the rotary valve. A central flow channel is provided at the center of the guide ring, and the central flow channel is connected to the filter outlet of the filter joint; 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 is provided with a guide ring flow channel; the center of the guide ring support is provided with a conical through hole; the rear end face of the front part of the guide ring presses 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 are combined to form a conical flow channel, and the outlet of the conical flow channel is arc-shaped;

[0023] The rear end of the guide ring support is in sequence the piston sleeve, the piston, the piston upper end cover, the piston outer tube, the spring, and the piston cylinder; the front end of the piston passes through the piston sleeve and penetrates 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; in a normal state, the piston presses against the inner end face of the piston upper end cover, at which time the piston head blocks the outlet of the tapered flow channel, and the piston is a hollow structure so that the flushing liquid flows through the piston along the central flow channel and enters the piston cavity; when the piston presses against the outer end face of the piston cylinder, the piston head completely opens the outlet of the tapered flow channel.

[0024] Specifically, the piston cylinder body is a cylindrical structure, and the piston rod cylinder body is provided with evenly distributed positioning palms around the circumference, and the positioning palms are provided with bolt holes. The piston cylinder body contains a piston cavity, and the tail of the piston cylinder body is a drive short-circuit connection end, which is used to match the drive short-circuit internal instrument string drive head.

[0025] Specifically, the circuit conversion connector is a double-mother structure, including a circuit conversion connector cylinder body, and three wire holes are provided on the outer wall of one side of the circuit conversion connector cylinder body, which are evenly distributed in a 120° circle. The wire holes communicate with the end face of the outer wall of one side of the circuit conversion connector cylinder body and the center through hole. A first insulated wire is provided in each wire hole, and a first guide ring is provided on the end face of the outer wall of one side of the circuit conversion connector cylinder body. The first guide ring is connected to the first insulated wire. An aviation plug is provided at one end of the center through hole, and a battery connector is provided at the other end of the center through hole. The first guide ring is connected to the battery connector through the first insulated wire, and the battery connector is connected to the aviation plug through the first insulated wire.

[0026] An industrial control method for a composite mud pulse measurement while drilling system in an underground coal mine comprises the following steps: controlling the water injection pressure value of a mud pump; when the pressure signal is greater than a set value K1 and less than K2, adopting mode 1 for data acquisition; and when the pressure signal is greater than the set value K2, adopting mode 2 for data acquisition; wherein mode 1 measures drilling trajectory parameters, and mode 2, in addition to collecting drilling trajectory parameters, also collects drilling engineering parameters and geological parameters; the specific parameter categories are determined by the type of acquisition module integrated in the measurement while drilling short circuit;

[0027] 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 overlapping area of ​​the stator flow channel and the rotor flow channel changes, and ΔP is recorded. Max That is, the overlapping area of ​​the stator flow channel and the rotor flow channel is at the maximum position, and the drive shaft of the brake servo motor is in this position. This process is the servo motor self-test zeroing process; at this time, the short-circuit internal solenoid valve is driven to send a control signal, driving the small valve head of the solenoid valve to move, thereby controlling the positive pulse short-circuit piston to block and open the conical flow channel formed by the guide ring and the guide ring support according to the specific code, thereby generating a positive pressure pulse;

[0028] Mode 2: The acquisition module collects drilling trajectory parameters while collecting drilling engineering parameters and geological parameters. The main control module encodes and modulates the collected data. At this time, the main control module also controls the servo motor to perform the self-test and zeroing process, and then controls the servo motor to drive the rotor to rotate according to a specific code. The overlapping area of ​​the stator flow channel and the rotor flow channel changes periodically, forming continuous mud pulses.

[0029] Compared with the prior art, the present invention has the following technical effects:

[0030] The composite mud pulse measurement while drilling system of the present invention integrates the positive pulse and continuous pulse generating devices together through side wall wiring, which can realize the independent operation of positive pulse short circuit and rotary valve short circuit, meeting the requirements of uploading small data volumes while also meeting the requirements of uploading large data volumes. The alternating operation of positive pulse short circuit and rotary valve short circuit effectively reduces the system power consumption.

[0031] The system of the present invention is suitable for various construction conditions underground. It can upload drilling trajectory parameters through positive pulses to guide conventional directional drilling construction. At the same time, it can upload drilling trajectory parameters, drilling engineering parameters, geological parameters and other types of parameters through continuous pulses. It can effectively guide the construction of various types of directional drilling such as directional drilling of coal seams, water exploration and drainage holes, and geological anomaly exploration holes.

[0032] The system of the present invention has two working modes. The mode selection is performed by controlling the water supply pressure, thereby realizing mode switching under different working conditions. The process is simple to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] FIG1 is a schematic diagram of the overall connection of the system of the present invention;

[0034] FIG2 is a cross-sectional view of a pulse generator assembly of the system of the present invention;

[0035] FIG3 is a front view of a circuit converter of a pulse generator assembly of the system of the present invention;

[0036] FIG4 is a cross-sectional view of the pulse generator assembly circuit converter BB of the system of the present invention;

[0037] FIG5 is a cross-sectional view of the pulse generator assembly AA of the system of the present invention;

[0038] FIG6 is a front view of the stator of the pulse generator assembly of the system of the present invention;

[0039] FIG7 is a cross-sectional view of the stator CC of the pulse generator assembly of the system of the present invention;

[0040] FIG8 is a front view of the rotor of the pulse generator assembly of the system of the present invention;

[0041] FIG9 is a cross-sectional view of the rotor DD of the pulse generator assembly of the system of the present invention;

[0042] 10 is a cross-sectional view of the outer tube of the rotary valve short-circuit side wall of the present invention;

[0043] FIG11 is a cross-sectional view of a filter connector of a pulse generator assembly of the system of the present invention;

[0044] FIG12 is a front view of the guide ring of the pulse generator assembly of the system of the present invention;

[0045] FIG13 is a cross-sectional view of the guide ring EE of the pulse generator assembly of the system of the present invention;

[0046] FIG14 is a front view of the lower cylinder of the pulse generator assembly of the system of the present invention;

[0047] 15 is a cross-sectional view of the lower cylinder FF of the pulse generator assembly of the system of the present invention;

[0048] FIG16 is a cross-sectional view of the circuit conversion connector of the system of the present invention;

[0049] FIG17 is a flow chart of a method for using the system of the present invention.

[0050] The meanings of the various numbers in the figure are: 1. Rotary valve short circuit, 2. Positive pulse short circuit, 3. Drive short circuit, 4. Circuit conversion connector; 101. Circuit converter, 102. Motor housing, 103. Stator, 104. Rotor, 105. Rotary valve outer tube, 106. Universal joint; 201. Filter connector, 202. Guide ring, 203. Guide ring support, 204. Piston, 205. Piston upper end cover, 206. Piston outer tube, 207. Piston cylinder, 208. Spring, 209. Piston jacket, 210. Positive pulse outer tube; 401. Circuit conversion connector cylinder, 402. First insulated wire, 403. First guide ring, 404. Aviation plug, 405. Battery connector; 1011. Center air plug, 1012. Sector-shaped flow channel, 1013. End cover, 1014. Second guide ring, 1015. Second insulated conductor; 1021. Motor protective housing, 1022. Fixing bolt; 1031. Stator flow channel, 1032. Center through hole, 1033. Positioning hole; 1041. Rotor bearing outer ring, 1042. Rotor bearing inner disc, 1043. Bearing ball, 1044. Rotor flow channel, 1045. Drive shaft, 1046. Center positioning hole, 1047. Retaining ring; 1051. Rotary valve outer tube housing, 1052. Third guide ring, 1053. Fourth guide ring, 1054. Housing positioning hole, 1055. Third insulated conductor; 2011. Positioning boss, 2012. Filter hole, 2013. Filter outlet; 2021. Guide ring flow channel, 2022. Conical boss, 2023. Central flow channel; 2071. Positioning palm, 2072. Bolt hole, 2073. Piston cavity, 2074. Drive short-circuit connection end. DETAILED DESCRIPTION

[0051] Specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent modifications made on the basis of the technical solution of this application fall within the protection scope of the present invention.

[0052] Example 1:

[0053] As shown in FIG1 to FIG16 , this embodiment provides a composite mud pulse measurement while drilling system for an underground coal mine, comprising 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.

[0054] 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 the rotary valve outer tube 105 and connected in sequence; a servo motor is arranged in the motor housing 102, a plurality of stator flow passages 1031 are provided on the stator 103, and a plurality of rotor flow passages 1044 are provided on the rotor 104.

[0055] 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 cover 205, a spring 208, a piston 204, a guide ring support 203, The guide ring 202 and the filter joint 201; the front end of the filter joint 201 is connected to the rotor 104, and the rear end of the filter joint 201 is connected to the central flow channel 2023 of the guide ring 202, and a conical flow channel can be formed between the guide ring 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 is deeply inserted into the piston cavity 2073 surrounded by the piston cylinder body 207, the piston outer tube 206 and the piston upper end cover 205, and 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.

[0056] A solenoid valve is installed in drive short circuit 3, which controls the movement of piston 204 in positive pulse short circuit 2, thereby controlling the blocking or opening of the tapered flow channel between guide ring 202 and guide ring support 203, thereby controlling the generation of positive pressure pulses. Specifically, when the tapered flow channel is open, the fluid flow pressure is stable. When the tapered flow channel is closed, the pressure increases, and the pressure pulses generated by the alternating opening and closing of the tapered flow channel are positive pulses.

[0057] When the pump is not turned on, the piston relies on the spring push to block the tapered flow channel; when the pump is turned on and no pulse signal is sent, the fluid pressure difference causes the piston to move to the right a certain distance until the force of the spring is balanced with the force of the valve head. At this time, the tapered flow channel opens a certain area and no longer increases; the drive short circuit is a conventional product. There is an electromagnetic valve structure inside the drive short circuit, which will extend or retract the solenoid valve head according to specific coding rules. When the pump is turned on and a pulse signal is sent, the solenoid valve inside the drive short circuit is closed (that is, the solenoid valve head is extended). At this time, the closed cavity 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 center hole. The lower end face of the piston is subjected to the high pressure, causing the piston to move upward to reduce the area of ​​the tapered 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, generating a positive pulse.

[0058] After the mud pump is turned on, liquid flows in along the tapered flow channel and the filter joint and flows into the channel inside the piston. When no pulse is sent, the solenoid valve inside the drive short circuit is in an open state (i.e., the solenoid valve head is retracted), resulting in the cavity at the lower end of the piston being 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 tapered flow channel, pushing the piston to move right to open the tapered flow channel; the liquid flowing out of the tapered flow channel flows through the annular gap between the piston cylinder and the positive pulse outer tube.

[0059] The front end of the rotary valve short circuit 1 is connected in sequence to multiple drill pipes, water feeders, pressure transmitters, and orifice explosion-proof computers; the rear end of the circuit conversion connector 4 is connected in sequence to the battery tube short circuit and the downhole measurement short circuit; the battery tube short circuit can power the composite mud pulse downhole measurement system; the downhole measurement short circuit includes an acquisition module and a main control module. The acquisition module can acquire drilling trajectory parameters, drilling engineering parameters and geological parameters. The main control module can encode and modulate the acquired parameters and control the operation of the servo motor in the rotary valve short circuit 1, so as to control the rotation of the rotor 104 to cause the overlapping area of ​​the stator overflow channel 1031 and the rotor overflow channel 1044 to change periodically, thereby forming a continuous mud pulse; the main control module can also control the action of the internal solenoid valve of the drive short circuit 3 to form a mud positive pulse.

[0060] 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. There is a fan-shaped flow channel 1012 between adjacent wire bridges. The front and rear ends of the inner ring are respectively equipped with end covers 1013 and a central aviation plug 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 central aviation plug 1011. Specifically, in this embodiment, the outer ring and the inner ring are both 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 along the circumference.

[0061] The motor case 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 limit blocks, and the ends of the rectangular limit blocks are provided with limit holes. The motor protective shell 1021 is limited to the inner wall of the outer tube 105 of the rotary valve through the limit holes and the fixing bolts 1022 inside; in this embodiment, there are three rectangular limit 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 and the motor protective shell 1021 are axially rigidly connected. The main shaft of the servo motor passes through the rear end of the motor protective shell 1021 and the main shaft and the rear end of the motor protective shell 1021 are dynamically sealed. The servo motor terminal is connected to the front end aviation plug of the motor protective shell 1021, and the front end aviation plug is matched with the center aviation plug 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.

[0062] The stator 103 is a disc-shaped structure, and is fixed to the inner wall of the outer tube 105 of the rotary valve by multiple positioning holes 1033 on its outer wall and bolts. In this embodiment, there are three positioning holes 1033 and they are evenly distributed along the circumference of the outer wall of the stator 103. A central through hole 1032 is provided in the center of the stator 103, and the rotor 104 can pass through the central through hole 1032. The stator 103 is provided with four stator flow channels 1031 evenly distributed at 90° around the circumference. The stator flow channels 1031 are fan-shaped, and the stator flow channels 1031 are chamfered 5mm near the contour of the flushing liquid inlet end to form a guide groove structure with a diversion function.

[0063] Rotor 104 comprises, arranged from outside to inside, a rotor bearing outer ring 1041, bearing balls 1043, and a rotor bearing inner disk 1042. Multiple rotor flow channels 1044 are located on the inner disk 1042. A drive shaft 1045 is located at the center of the inner disk 1042. The front end of the drive shaft 1045 is connected to the universal joint 106, and the rear end of the drive shaft 1045 is provided with a center positioning hole 1046. The drive shaft 1045 is mechanically connected to the universal joint 106. Adjusting the depth of the connection between the universal joint 106 and the drive shaft 1045 controls the distance between rotor 104 and stator 103. The distance is adjustable within a range of 2 to 5 mm, thereby controlling the amplitude of the pressure pulse. After the rotor bearing outer ring 1041, bearing balls 1043, and 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. This retaining ring prevents the flushing fluid from releasing pressure through the gaps between the bearing balls 1043. The central positioning hole 1046 is connected to the filter joint 201 on the upper part of the positive pulse short circuit 2. The filter joint 201 provides radial support for the rotor 104. The bearing structure outside the rotor 104 provides radial limitation and can also ensure the smooth rotation of the rotor 1044.

[0064] The rotary valve outer tube 105 includes a rotary valve outer tube housing 1051. A wire hole is provided in the wall of the rotary valve outer tube housing 1051. A third insulated wire 1055 is provided in the wire 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 side wall wiring structure. The inner wall of the rotary valve outer tube housing 1051 is provided with three 120° circumferentially evenly distributed wires. There are wire holes, each of which is provided 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; there are two groups of shell positioning holes 1054 on the side wall of the outer tube shell 1051 of the rotary valve, and both groups of shell positioning holes 1054 are three and evenly distributed in a 120° circle. One group of shell positioning holes 1054 is used to limit and fix the motor protective shell 1021, and the other group of shell positioning holes 1054 is used to limit and fix the stator 103.

[0065] After the circuit converter 101 is mated with the rotary valve outer tube 105, the second guide ring 1014 and the fourth guide ring 1053 are pressed together, thereby establishing electrical continuity between the second insulated conductor 1015 and the third insulated conductor 1055, which can then be used to power the motor. Similarly, the positive pulse outer tube 210 and the drive short circuit 3 outer tube both utilize the same wiring principles. The mating connection between the outer tubes compresses the end faces of their respective guide rings, thus achieving electrical continuity.

[0066] The filter joint 201 is a hollow structure. A positioning boss 2011 is provided at the front end of the filter joint 201 to plug into the center positioning hole 1046, and a filter outlet 2013 is provided at the rear end. A plurality of filter holes 2012 are provided on the side wall of the filter joint 201, which can effectively filter solid particles with a diameter of ≥1 mm. The flushing liquid flows into the outer wall of the filter joint 201 and flows out along the filter outlet 2013; the rear end of the filter joint 201 is connected to the guide ring 202.

[0067] The guide ring 202 is arranged on the step surface of the inner wall of the positive pulse outer tube 210 and is tightened by the rotary valve outer tube 105. A central flow channel 2023 is provided in the center of the guide ring 202, and the central flow channel 2023 is connected to the filter outlet 2013 of the filter joint 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 is provided with three guide ring flow channels 2021 evenly distributed in a 120° circle; a conical through hole is provided in the center of the guide ring support 203; the rear end face of the front part of the guide ring 202 presses 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 are combined to form a conical flow channel, and the outlet of the conical flow channel is arc-shaped.

[0068] The rear end of the guide ring support 203 is in sequence the piston sleeve 209, the piston 204, the piston upper end cover 205, the piston outer tube 206, the spring 208, and the piston cylinder 207; the front end of the piston 204 passes through the piston sleeve 209 and penetrates 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 presses against the spring 208; under normal conditions, the piston 204 presses against the inner end face of the piston upper end cover 205. At this time, the piston 204 head of the piston 204 blocks the outlet of the conical flow channel. The piston 204 is a hollow structure so that the flushing liquid flows through the piston 204 along the central flow channel 2023 and enters the piston cavity 2073; the piston 204 can freely move a certain distance in the cavity, which is the distance from the inner end face of the piston upper end cover 205 to the piston cylinder 207 The distance between the outer end surfaces is such that when the piston 204 reaches the outer end surface of the piston cylinder 207 , the piston head 204 of the piston 204 completely opens the outlet of the tapered flow channel.

[0069] The piston cylinder body 207 is a cylindrical structure. The piston 204 rod cylinder body is circumferentially provided with three positioning legs 2071 evenly distributed in a 120° circle. The positioning legs 2071 are each provided with a bolt hole 2072. The piston cylinder body 207 contains a piston cavity 2073. The tail of the piston cylinder body 207 is a drive short-circuit connection end 2074. The drive short-circuit connection end 2074 is used to connect the drive short-circuit 3 internal instrument string drive head.

[0070] The circuit conversion connector 4 is a double-mother structure, and its function is to transform the side wall wiring structure into a center wire-passing structure, thereby matching the built-in battery cartridge of the rear battery cartridge short circuit, so that it can power the internal solenoid valve of the upper drive short circuit and the internal servo motor of the rotary valve short circuit 1; the circuit conversion connector 4 includes a circuit conversion connector cylinder 401, and the outer wall of one side of the circuit conversion connector cylinder 401 is provided with three wire-passing holes evenly distributed in a 120° circle. The wire-passing holes communicate with the outer wall end face of one side of the circuit conversion connector cylinder 401 and the center through hole 1032. A first insulated wire 402 is provided in each wire-passing hole, and a first guide ring 403 is provided on the outer wall end face 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 center through hole 1032, and a battery connector 405 is provided at the other end of the center through hole 1032. The first guide ring 403 is connected to the battery connector 405 through the first insulated wire 402, and the battery connector 405 is connected to the aviation plug 404 through the first insulated wire 402.

[0071] The first guide ring 403, the second guide ring 1014, the third guide ring 1052 and the contact parts between the guide rings and the pipe body in other pipe bodies are all insulated. Insulation glue can be applied to the insulation surface during the installation of the guide rings.

[0072] Example 2:

[0073] This embodiment provides an industrial control method for a composite mud pulse measurement while drilling system for an underground coal mine according to claim 1. As shown in FIG17 , the measurement while drilling short circuit is not limited to the collection of drilling trajectory parameters, but may also include the collection of drilling engineering parameters (temperature, rotation speed, vibration, internal pressure of the drill tool, external pressure of the drill tool, torque, bit pressure, etc.) and geological parameters (gamma value, resistivity, etc.). Under the above-mentioned multiple types of data collection conditions, in order to realize the need to alternately collect different types and quantities of parameters during the same drilling construction, the specific steps are as follows: controlling the water injection pressure value of the mud pump; when the pressure signal collected by the pressure sensor inside the main control module is greater than the set value K1 and less than K2, the main control board adopts mode 1 for data collection; when the pressure signal collected by the pressure sensor inside the main control module is greater than the set value K2, the main control board adopts mode 2 for data collection, wherein mode 1 measures drilling trajectory parameters (azimuth, inclination, tool face), and mode 2 collects drilling engineering parameters and geological parameters in addition to drilling trajectory parameters. The specific parameter category is determined by the type of collection module integrated in the measurement while drilling short circuit.

[0074] Specifically, the following modes are included:

[0075] Mode 1: The acquisition module collects drilling trajectory parameters (azimuth, inclination, tool face), and 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 to rotate. During the rotor rotation, the overlapping area of ​​the stator flow channel and the rotor flow channel changes, and the motor drive module records ΔP Max The maximum position (i.e., the position where the overlapping area of ​​the stator flow channel and the rotor flow channel is the largest), and the drive shaft of the brake servo motor is in this position, this process is the servo motor self-test zeroing process; at this time, the control module sends a control signal to the solenoid valve in the drive short circuit, driving the small valve head of the solenoid valve to move, thereby controlling the positive pulse short circuit piston movement, and blocking and opening 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 according to the specific code, thereby generating a positive pressure pulse;

[0076] Mode 2: The acquisition module collects drilling trajectory parameters (azimuth, inclination, tool face) while collecting drilling engineering parameters (temperature, speed, vibration, internal pressure of the drill tool, external pressure of the drill tool, torque, bit pressure, etc.) and geological parameters (gamma value, resistivity, etc.). The main control module encodes and modulates the collected data. At this time, the main control module also sends a control signal to the motor drive module to drive the servo motor to perform the self-test and zeroing process. After that, the servo motor drives the rotor to rotate according to the specific code. The overlapping area of ​​the stator flow channel and the rotor flow channel changes periodically, forming a continuous mud pulse.

Claims

1. A composite mud pulse measurement while drilling system for coal mines, characterized in that: It comprises a rotary valve short circuit (1), a positive pulse short circuit (2), a drive short circuit (3) and a circuit conversion joint (4) which are connected in sequence; The rotary valve short circuit (1) comprises a rotary valve outer tube (105), and a circuit converter (101), a motor housing (102), a universal shaft (106), a stator (103) and a rotor (104) which are arranged in the rotary valve outer tube (105) and are connected in sequence; a servo motor is arranged in the motor housing (102), a plurality of stator flow passages (1031) are arranged on the stator (103), and a plurality of rotor flow passages (1044) are arranged on the rotor (104); The positive pulse short circuit (2) comprises a positive pulse outer tube (210), and a piston sleeve (209), a piston cylinder (207), a piston outer tube (206), a piston upper end cover (205), a spring (208), a piston (204), a guide ring support (203), a guide ring (202) and a filter joint (201) arranged in the positive pulse outer tube (210); the front end of the filter joint (201) is connected to the rotor (104), and the rear end of the filter joint (201) is connected to the guide ring (20 2), a conical flow channel can be formed between the guide ring (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) penetrates into a piston cavity (2073) surrounded by a piston cylinder body (207), a piston outer tube (206) and a piston upper end cover (205), and the rear end of the piston (204) contacts the spring (208) in the piston cavity (2073); The driving short circuit (3) is provided with an electromagnetic valve, which can control the action of the piston (204) in the positive pulse short circuit (2) to control the blocking or opening of the tapered flow channel, thereby controlling the generation of a pressure positive pulse; The front end of the rotary valve short circuit (1) is connected in sequence to a plurality of drill rods, a water feeder, a pressure transmitter, and an orifice explosion-proof computer; the rear end of the circuit conversion joint (4) is connected in sequence to a battery cartridge short circuit and a while-drilling measurement short circuit; the while-drilling measurement short circuit comprises a collection module and a main control module, the collection module can collect drilling trajectory parameters, drilling engineering parameters and geological parameters, the main control module can encode and modulate the collected parameters and can control the operation of the servo motor in the rotary valve short circuit (1), so as to control the rotation of the rotor (104) so ​​that the overlapping area of ​​the stator flow channel (1031) and the rotor flow channel (1044) changes periodically, thereby forming a continuous mud pulse; the main control module can also control the action of the internal electromagnetic valve of the drive short circuit (3) to form a positive mud pulse.

2. The coal mine underground composite mud pulse measurement while drilling system according to claim 1, characterized in that: The circuit converter (101) comprises 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 passage (1012) is formed between adjacent wire bridges. End covers (1013) and a central aviation plug (1011) are respectively installed at the front and rear ends of the inner ring. A second guide ring (1014) is sleeved on the outer ring. A second insulated wire (1015) in the wire bridge connects the second guide ring (1014) and the central aviation plug (1011).

3. The coal mine underground composite mud pulse measurement while drilling system according to claim 2, characterized in that: The motor housing (102) comprises a cylindrical motor protection shell (1021) and a servo motor therein; the outer wall of the motor protection shell (1021) is provided with a plurality of rectangular limit blocks, and the ends of the rectangular limit blocks are provided with limit holes, and the motor protection shell (1021) is limited to the inner wall of the outer tube (105) of the rotary valve through the limit holes and the fixing bolts (1022) therein; the servo motor has a built-in reducer, the servo motor and the motor protection shell (1021) are axially rigidly connected, the main shaft of the servo motor passes through the rear end of the motor protection shell (1021), and the main shaft and the rear end of the motor protection shell (1021) are dynamically sealed, the servo motor connection terminal is connected to the front end aviation plug of the motor protection shell (1021), and the front end aviation plug is matched with the central aviation plug (1011); The front end of the universal shaft (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), so as to stably transmit the power of the servo motor to the rotor (104).

4. The coal mine underground composite mud pulse measurement while drilling system according to claim 1, characterized in that: 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 a plurality of positioning holes (1033) on its outer wall and bolts. A central through hole (1032) is provided at the center of the stator (103). The rotor (104) can pass through the central through hole (1032). The stator (103) is provided with four stator flow passages (1031) evenly distributed at a 90° circle. The stator flow passages (1031) are fan-shaped. The stator flow passages (1031) are chamfered by 5 mm near the contour of the flushing liquid inflow end to form a guide groove structure with a guide function. The rotor (104) comprises a rotor bearing outer ring (1041), a bearing ball (1043) and a rotor bearing inner disk (1042) arranged from outside to inside, and a plurality of rotor flow passages (1044) are provided on the rotor bearing inner disk (1042); the center of the rotor bearing inner disk (1042) is a transmission shaft (1045), the front end of the transmission shaft (1045) is connected to the universal shaft (106), and the rear end of the transmission shaft (1045) is provided with a center positioning hole (1046).

5. The coal mine underground composite mud pulse measurement while drilling system according to claim 1, characterized in that: The rotary valve outer tube (105) comprises a rotary valve outer tube shell (1051), a wire hole is provided in the wall of the rotary valve outer tube shell (1051), a third insulated wire (1055) is provided in the wire hole, and 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 shell (1051); 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 tightly, thereby making the second insulated wire (1015) and the third insulated wire (1055) conductive.

6. The coal mine underground composite mud pulse measurement while drilling system according to claim 4, characterized in that: The filter joint (201) is a hollow structure; a positioning boss (2011) is provided at the front end of the filter joint (201) to be plugged into and fit with the central positioning hole (1046); a filter outlet (2013) is provided at the rear end; a plurality of filter holes (2012) are provided on the side wall of the filter joint (201) to effectively filter solid particles with a diameter of ≥1 mm; flushing liquid flows in from the outer wall of the filter joint (201) and flows out along the filter outlet (2013); and the rear end of the filter joint (201) is connected to a guide ring (202).

7. The coal mine underground composite mud pulse measurement while drilling system according to claim 1, characterized in that: The guide ring (202) is arranged on the inner wall step surface of the positive pulse outer tube (210) and is tightened by the rotary valve outer tube (105); a central flow passage (2023) is arranged at the center of the guide ring (202), and the central flow passage (2023) is connected with the filter outlet (2013) of the filter joint (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) is provided with a guide ring flow passage (2021); the center of the guide ring support (203) is provided with a conical through hole; the rear end face of the front part of the guide ring (202) presses 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) are combined to form a conical flow channel, and the outlet of the conical flow channel is arc-shaped; The rear end of the guide ring support (203) is in sequence a piston sleeve (209), a piston (204), a piston upper end cover (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 sleeve (209) and penetrates into the central flow passage (2023) of the guide ring (202); the rear end of the piston (204) is located in the piston cavity (2073) and presses against the spring (208); in a normal state, , the piston (204) presses against the inner end surface of the piston upper end cover (205), at which time the piston (204) head of the piston (204) blocks the outlet of the tapered flow channel, and the piston (204) is a hollow structure so that the flushing liquid flows through the piston (204) along the central flow channel (2023) and enters the piston cavity (2073); when the piston (204) presses against the outer end surface of the piston cylinder body (207), at this time the piston (204) head of the piston (204) completely opens the outlet of the tapered flow channel.

8. The coal mine underground composite mud pulse measurement while drilling system according to claim 1, characterized in that: The piston cylinder body (207) is a cylindrical structure, and the piston (204) rod cylinder body is provided with evenly distributed positioning legs (2071) around the piston (204), and the positioning legs (2071) are provided with bolt holes (2072). The piston cylinder body (207) is a piston cavity (2073), and the tail of the piston cylinder body (207) is a driving short-circuit connection end (2074), and the driving short-circuit connection end (2074) is used to match the driving short-circuit (3) internal instrument string drive head.

9. The coal mine underground composite mud pulse measurement while drilling system according to claim 1, characterized in that: The circuit conversion connector (4) is a double-mother structure, comprising a circuit conversion connector cylinder (401), wherein the outer wall of one side of the circuit conversion connector cylinder (401) is provided with three wire holes evenly distributed in a 120° circle, the wire holes communicating with the outer wall end face of one side of the circuit conversion connector cylinder (401) and the central through hole (1032), each of the wire holes being provided with a first insulating wire (402), the outer wall end face of one side of the circuit conversion connector cylinder (401) being provided with a first guide ring (403), the first guide ring (403) being connected to the first insulating wire (402), one end of the central through hole (1032) being provided with an aviation plug (404), the other end of the central through hole (1032) being provided with a battery connector (405), the first guide ring (403) being connected to the battery connector (405) via the first insulating wire (402), and the battery connector (405) being connected to the aviation plug (404) via the first insulating wire (402).

10. An industrial control method for the composite mud pulse measurement while drilling system in coal mines according to claim 1, characterized in that: The steps are as follows: control the water injection pressure value of the mud pump, when the pressure signal is greater than the set value K1 and less than K2, use mode 1 for data acquisition, when the pressure signal is greater than the set value K2, use mode 2 for data acquisition, wherein mode 1 measures the drilling trajectory parameters, and mode 2 collects drilling engineering parameters and geological parameters in addition to the drilling trajectory parameters. The specific parameter category is determined by the type of acquisition module integrated by the measurement while drilling short circuit; Mode 1: The acquisition module acquires drilling trajectory parameters, and the main control module controls the servo motor to control the rotor rotation. During the rotor rotation, the overlapping area of ​​the stator flow channel and the rotor flow channel changes, and ΔP is recorded. Max That is, the overlapping area of ​​the stator flow channel and the rotor flow channel is at the maximum position, and the drive shaft of the brake servo motor is at this position. This process is the self-checking and zeroing process of the servo motor. At this time, the short-circuited internal solenoid valve is driven to send a control signal, driving the small valve head of the solenoid valve to move, thereby controlling the positive pulse short-circuited piston to move, and according to the specific code, the conical flow channel formed by the guide ring and the guide ring support is blocked and opened, thereby generating a pressure positive pulse. Mode 2: The acquisition module collects drilling trajectory parameters while collecting drilling engineering parameters and geological parameters. The main control module encodes and modulates the collected data. At this time, the main control module also controls the servo motor to perform the self-test zeroing process, and then controls the servo motor to drive the rotor to rotate according to a specific code. The overlapping area of ​​the stator flow channel and the rotor flow channel changes periodically, forming a continuous mud pulse.

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