A real-time monitoring system for weight of discharged coal powder based on drill cuttings method and use method thereof

Abstract

The present application relates to a kind of based on drilling cuttings method's discharge coal dust weight real-time monitoring system and use method, system includes drill bit, drill pipe, powder collection telescopic cylinder, powder collection fixed cylinder, drilling machine, air compressor, coal dust collection monitoring system and control system, wherein, drill pipe is hollow drill pipe, one end of drill pipe is connected with drilling machine, the middle part of drill pipe is connected with the bottom of drilling machine by drill pipe clamping device, the other end of drill pipe is connected with drill bit, drill pipe is connected with air compressor, one end of drill pipe clamping device is connected with powder collection fixed cylinder by L type fixed connecting rod, powder collection fixed cylinder is sleeved with drill pipe, powder collection telescopic cylinder is slidably connected in powder collection fixed cylinder by telescopic track, the downside of powder collection fixed cylinder is connected with coal dust collection monitoring system by air outlet pipeline, drilling machine, air compressor and coal dust collection monitoring system are all connected with control system.The present application improves drilling cuttings collection effect, guarantees monitoring accuracy, while automatically measuring coal powder amount in the process of drilling, realizes the real-time measurement to discharge coal dust weight.

Description

Technical Field

[0001] This invention relates to a real-time monitoring system and method for the weight of discharged pulverized coal based on drill cuttings method, belonging to the technical field of mining equipment. Background Technology

[0002] The drill cuttings method is a widely used method for monitoring rockburst hazards. This method involves drilling a 42mm diameter borehole in the coal seam and identifying the rockburst hazard based on the amount of coal dust discharged and its variation, as well as the relevant dynamic phenomena during the drilling process. It is a practical and reliable method for judging rockburst hazards.

[0003] CN115265726A discloses a coal powder quality measuring device and method for the coal mine drill cuttings method, relating to the technical field of coal powder weighing devices. This coal powder quality measuring device for the coal mine drill cuttings method includes a powder collecting and fixing cylinder, a powder collecting and telescopic cylinder, a powder collecting and transferring cylinder, a powder collecting and fixing mechanism, a drill rod, a housing, a weighing sensor, a support base, a coal powder conveyor belt, a powder collecting trough, a flexible connecting sleeve, a powder discharging trough, a weighing support mechanism, and a data acquisition and processing unit. This device uses helical blades on the drill rod to drive the drill cuttings, but the helical blades have poor drill cuttings collection efficiency, making it difficult to achieve full collection of drill cuttings. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a real-time monitoring system for the weight of discharged coal dust based on the drill cuttings method. This system improves the efficiency of drill cuttings collection, ensures monitoring accuracy, and automatically measures the amount of coal dust during the drilling process, enabling real-time measurement of the weight of discharged coal dust.

[0005] The present invention also provides a method for using the above-mentioned real-time monitoring system for the weight of discharged pulverized coal based on the drill cuttings method.

[0006] The technical solution of the present invention is as follows:

[0007] A real-time monitoring system for the weight of discharged pulverized coal based on drill cuttings method includes a drill bit, drill rod, pulverized coal collection telescopic cylinder, pulverized coal collection fixed cylinder, drilling rig, air compressor, pulverized coal collection monitoring system, and control system.

[0008] The drill rod is a hollow drill rod. One end of the drill rod is connected to the drilling rig, and the middle of the drill rod is connected to the bottom of the drilling rig through a drill rod clamping device to improve the working stability of the drill rod. The other end of the drill rod is connected to the drill bit, and an air compressor is connected to the outside of the drill rod. One end of the drill rod clamping device is connected to a dust collection and fixing cylinder through an L-shaped fixed connecting rod. The drill rod is installed inside the dust collection and fixing cylinder. Three telescopic rails are evenly distributed on the inner wall of the dust collection and fixing cylinder. The dust collection and telescopic cylinder is slidably connected to the dust collection and fixing cylinder through the telescopic rails. The lower side of the dust collection and fixing cylinder is connected to a coal dust collection and monitoring system through an air outlet pipe. The drilling rig, air compressor, and coal dust collection and monitoring system are all connected to a control system.

[0009] According to a preferred embodiment of the present invention, the diameter of the drill bit front end is larger than the diameter of the rear neck section, the diameter of the drill bit front end is the same as the outer diameter of the powder collecting telescopic cylinder, a plurality of air inlets connected to the drill rod are arranged around the middle of the drill bit, a plurality of powder outlet channels are arranged around the outer periphery of the drill bit front end, the end of the powder outlet channel penetrates the neck section of the drill bit, and the end of the powder outlet channel is located inside the powder collecting telescopic cylinder, which facilitates the collection of drill cuttings.

[0010] According to a preferred embodiment of the present invention, a plurality of wedge-shaped grooves are provided around the outer side of the front end of the drill bit, and the depth of the wedge-shaped grooves gradually becomes shallower from the front end of the drill bit to the rear. The larger-diameter debris at the bottom can be lifted up through the wedge-shaped grooves.

[0011] According to a preferred embodiment of the present invention, the drill bit front end is provided with irregularly arranged protrusions, which can fully grind the drill cuttings during the drilling process.

[0012] According to a preferred embodiment of the present invention, a V-shaped groove track is provided around the front end of the drill rod, and at least two support rods are symmetrically arranged inside the front end of the powder collecting telescopic cylinder. The ends of the support rods are tapered and are located in the groove track, ensuring that the powder collecting telescopic cylinder does not rotate while the drill rod rotates. At the same time, the powder collecting telescopic cylinder can move axially with the drill rod.

[0013] According to a preferred embodiment of the present invention, a through rectangular slot is provided at the bottom of the rear end of the powder collecting telescopic cylinder, and a circular inner wall is provided at the rear end of the powder collecting fixed cylinder by means of a limiting block. The limiting block matches the slot, and the outer diameter of the inner wall is the same as the inner diameter of the powder collecting telescopic cylinder. A drill hole is left on the inner wall for the drill rod to pass through. The drill cuttings pass through the powder collecting telescopic cylinder to the inner wall of the rear end of the powder collecting fixed cylinder, and then enter the air outlet duct through the slot.

[0014] According to a preferred embodiment of the present invention, an annular blocking block is provided between the drill rod and the powder collecting telescopic cylinder. The blocking block is made of flexible material and fits against the inner wall of the rear end of the powder collecting fixed cylinder. A flexible rubber strip is provided between the front end of the powder collecting fixed cylinder and the powder collecting telescopic cylinder to prevent drill cuttings from leaking out between the powder collecting fixed cylinder and the powder collecting telescopic cylinder.

[0015] According to a preferred embodiment of the present invention, the coal dust collection and monitoring system includes a collection cylinder and a stress sensing device. A cylindrical stress sensing device is fixedly installed in the middle of the collection cylinder. An air outlet duct is connected to the outside of the collection cylinder above the stress sensing device. A filter screen is installed at the air outlet at the lower end of the collection cylinder.

[0016] According to a preferred embodiment of the present invention, a Venturi flow meter is installed in the air outlet duct for monitoring gas flow.

[0017] The steps for using the above-mentioned real-time monitoring system for the weight of discharged pulverized coal based on the drill cuttings method are as follows:

[0018] (1) The air compressor and drilling rig are started, the drill bit contacts the coal seam borehole and begins to produce powder. The air blown out by the air compressor enters the borehole through the drill rod and drill bit. The gas is fully mixed with the coal powder generated during the drilling process to form a two-phase flow of air and powder. The two-phase flow of air and powder enters the air outlet pipe after passing through the powder collection telescopic cylinder.

[0019] (2) The air-powder two-phase flow in the air outlet duct enters the coal powder collection and monitoring system. The air-powder two-phase flow blows directly towards the stress sensing device to obtain stress data. The Venturi flow meter in the air outlet duct monitors the gas flow rate. After passing through the stress sensing device, the air-powder two-phase flow enters the collection cylinder. The coal powder remains in the collection cylinder. The gas flows out after passing through the filter screen. The stress data and gas flow data are transmitted to the control system. After calculation, the stress-time curve and the coal powder mass-time curve are generated. The drilling status is judged based on the curve.

[0020] According to a preferred embodiment of the present invention, in step (2), the steps for generating the stress-time curve and the pulverized coal mass-time curve are as follows:

[0021] a. Stress data is directly acquired by the stress sensing device, and a stress-time curve is plotted with time as the horizontal axis and stress as the vertical axis.

[0022] b. The calculation process for pulverized coal quality data is as follows:

[0023] M =ρ×S×L (1)

[0024] Where M is the mass of pulverized coal, S is the cross-sectional area of ​​the exhaust duct, ρ is the gas density, and L is the length of the duct through which the gas flows.

[0025] R X =ρ×Q×V (2)

[0026] In the formula, R X The stress is measured by the stress sensing device, ρ is the gas density, Q is the gas flow rate during the measured time period, V is the gas velocity, V=Q / S, and the gas density ρ is obtained from equation (2);

[0027] L=V×t (3)

[0028] The length L of the pipe through which the gas flows is calculated by equation (3). Substituting the gas density ρ and the length L of the pipe through which the gas flows into equation (1), the coal powder mass changing with time can be obtained, and a coal powder mass-time curve can be plotted.

[0029] The beneficial effects of this invention are as follows:

[0030] 1. This invention enables real-time measurement of coal powder weight during the drilling process using drill cuttings. It is simple and convenient to operate, has high measurement accuracy, reduces the workload of observers, improves construction efficiency, and is safe and reliable.

[0031] 2. The present invention has a simple structure. The novel ventilation drill bit can fully grind the coal and rock mass, ensure smooth ventilation, and have a high degree of gas disorder, so that the coal powder and air can be mixed evenly. At the same time, the powder collection telescopic cylinder can move axially synchronously with the drill bit, so that the air-powder two-phase flow in the flow transfer process enters the powder collection telescopic cylinder in advance, which increases the flowability and solves the problem of large coal powder residue in the traditional slag discharge method, ensuring the reliability and accuracy of experimental data.

[0032] 3. The continuous air-powder two-phase flow calculation method of the present invention realizes the real-time measurement of coal powder weight, solves the discontinuity problem caused by the traditional unit drilling distance as the measurement method, and at the same time, the calculation method can improve the accuracy of the weighing part measurement.

[0033] 4. The present invention can determine abnormal drilling problems such as drill bit jacking, drill bit stuck, and drill bit suction during the drilling process by considering whether there are sudden changes in the stress-time curve and what kind of sudden changes, combined with the drill rod condition and whether there are abnormal noises. Based on the coal powder quality-time curve and the stress-time curve, it provides a basis for further judging the fracture distribution state in the drilling area.

[0034] 5. The range of powder output corresponding to the stable powder output wind speed under normal drilling conditions defined by this invention has a direct effect on the determination of the impact tendency of stress concentration areas or coal and rock fracture areas, and has good practicality. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the structure of the present invention;

[0036] Figure 2 This is a schematic diagram of the drill bit structure of the present invention;

[0037] Figure 3 This is a schematic diagram of the powder collection telescopic cylinder structure of the present invention;

[0038] Figure 4 This is a schematic diagram of the stress sensing device of the present invention;

[0039] Figure 5 This is a rear view diagram of the powder collection and fixing cylinder;

[0040] Figure 6 This is a stress-time curve obtained from an embodiment of the present invention;

[0041] Figure 7 This is a coal powder quality-time curve obtained in an embodiment of the present invention;

[0042] The components are as follows: 1. Drill bit; 2. Wedge-shaped groove; 3. Powder outlet channel; 4. Protrusion; 5. Air inlet; 6. Neck section; 7. Drill rod; 8. Powder collection telescopic cylinder; 9. Support rod; 10. Powder collection fixing cylinder; 11. Telescopic track; 12. Flexible rubber strip; 13. Blocking block; 14. Air outlet duct; 15. Empty slot; 16. Collection cylinder; 17. Fixed connecting rod; 18. Drill rod clamping device; 19. Gas flow channel; 20. Stress sensing device; 21. Filter screen; 22. Gas outlet duct; 23. Control system; 24. Drilling rig; 25. Drill rod air inlet; 26. Inner wall; 27. Limiting block. Detailed Implementation

[0043] The present invention will be further described below with reference to the embodiments and accompanying drawings, but is not limited thereto.

[0044] Example 1:

[0045] like Figure 1-4 As shown, this embodiment provides a real-time monitoring system for the weight of discharged pulverized coal based on the drill cuttings method, including a drill bit 1, a drill rod 7, a pulverized coal collection telescopic cylinder 8, a pulverized coal collection fixed cylinder 10, a drilling rig 24, an air compressor, a pulverized coal collection monitoring system, and a control system 23.

[0046] The drill rod 7 is a hollow drill rod. One end of the drill rod 7 is connected to the drilling machine 24. The middle part of the drill rod 7 is connected to the bottom of the drilling machine through the drill rod clamping device 18 to improve the working stability of the drill rod. The other end of the drill rod 7 is connected to the drill bit 1. An air compressor is connected to the outside of the drill rod 7. One end of the drill rod clamping device 18 is connected to the dust collection fixing cylinder 10 through an L-shaped fixed connecting rod 17. The drill rod 7 is installed inside the dust collection fixing cylinder 10. Three telescopic tracks 11 are evenly distributed on the inner wall of the dust collection fixing cylinder 10. The dust collection telescopic cylinder 8 is slidably connected to the dust collection fixing cylinder 10 through the telescopic tracks 11. The lower side of the dust collection fixing cylinder 10 is connected to the coal dust collection monitoring system through the air outlet pipe 14. The drilling machine 24, the air compressor and the coal dust collection monitoring system are all connected to the control system 23.

[0047] The diameter of the front end of the drill bit 1 is larger than the diameter of the rear neck section 6. The diameter of the front end of the drill bit 1 is the same as the outer diameter of the powder collection telescopic cylinder 8. Multiple air inlets 5 connected to the drill rod are arranged around the middle of the drill bit 1. Multiple powder outlet channels 3 are arranged around the front end of the drill bit 1. The end of the powder outlet channel 3 passes through the neck section 6 of the drill bit. The end of the powder outlet channel 3 is located inside the powder collection telescopic cylinder 8, which facilitates the collection of drill cuttings.

[0048] The drill rod 7 has a V-shaped groove track around its front end. The powder collection telescopic cylinder 8 has at least two support rods 9 symmetrically arranged inside its front end. The ends of the support rods are tapered and are set in the groove track to ensure that the powder collection telescopic cylinder does not rotate while the drill rod rotates. At the same time, the powder collection telescopic cylinder can move axially with the drill rod.

[0049] The bottom of the rear end of the powder collecting telescopic cylinder 8 is provided with a through rectangular slot 15. The length of the slot is determined according to the drilling length, which is sufficient to meet the extension requirements. The rear end of the powder collecting fixed cylinder 10 is provided with a circular inner wall 26 through a limiting block 27. The limiting block 27 matches the slot 15. The outer diameter of the inner wall 26 is the same as the inner diameter of the powder collecting telescopic cylinder. The gap between the inner wall and the powder collecting fixed cylinder is the movement gap of the powder collecting telescopic cylinder. A drill hole is left on the inner wall for the drill rod to pass through. The drill cuttings pass through the powder collecting telescopic cylinder to the inner wall of the rear end of the powder collecting fixed cylinder, and then enter the air outlet duct through the slot.

[0050] An annular blocking block 13 is provided between the drill rod 7 and the powder collecting telescopic cylinder 8. The blocking block is made of flexible material and fits against the inner wall of the rear end of the powder collecting fixed cylinder. A flexible rubber strip 12 is provided between the front end of the powder collecting fixed cylinder and the powder collecting telescopic cylinder to prevent drill cuttings from leaking out between the powder collecting fixed cylinder and the powder collecting telescopic cylinder.

[0051] The coal dust collection and monitoring system includes a collection cylinder 16 and a stress sensing device 20. A cylindrical stress sensing device 20 is fixedly installed in the middle of the collection cylinder 16. An air outlet duct 14 is connected to the outside of the collection cylinder above the stress sensing device 20. A filter screen 21 is installed at the air outlet at the lower end of the collection cylinder.

[0052] A Venturi flow meter is installed inside the air outlet duct 14 to monitor the gas flow rate.

[0053] The steps for using the above-mentioned real-time monitoring system for the weight of discharged pulverized coal based on the drill cuttings method are as follows:

[0054] (1) The air compressor and drilling rig are started, the drill bit contacts the coal seam borehole and begins to produce powder. The air blown out by the air compressor enters the borehole through the drill rod and drill bit. The gas is fully mixed with the coal powder generated during the drilling process to form a two-phase flow of air and powder. The two-phase flow of air and powder enters the air outlet pipe after passing through the powder collection telescopic cylinder.

[0055] (2) The air-powder two-phase flow in the outlet duct enters the pulverized coal collection and monitoring system. The air-powder two-phase flow blows directly towards the stress sensing device to obtain stress data. The Venturi flow meter in the outlet duct monitors the gas flow rate. After passing through the stress sensing device, the air-powder two-phase flow enters the collection cylinder. The pulverized coal remains in the collection cylinder, and the gas flows out after passing through the filter screen. The stress data and gas flow data are transmitted to the control system. After calculation, a stress-time curve is generated. Figure 6 Coal powder quality-time curve Figure 7 The steps for generating the stress-time curve and the pulverized coal quality-time curve are as follows:

[0056] a. Stress data is directly acquired by the stress sensing device, and a stress-time curve is plotted with time as the horizontal axis and stress as the vertical axis.

[0057] b. The calculation process for pulverized coal quality data is as follows:

[0058] M =ρ×S×L (1)

[0059] Where M is the mass of pulverized coal, S is the cross-sectional area of ​​the exhaust duct, ρ is the gas density, and L is the length of the duct through which the gas flows.

[0060] R X =ρ×Q×V (2)

[0061] In the formula, R X The stress is measured by the stress sensing device, ρ is the gas density, Q is the gas flow rate during the measured time period, V is the gas velocity, V=Q / S, and the gas density ρ is obtained from equation (2);

[0062] L=V×t (3)

[0063] The length L of the pipe through which the gas flows is calculated by equation (3). Substituting the gas density ρ and the length L of the pipe through which the gas flows into equation (1), the coal powder mass changing with time can be obtained, and a coal powder mass-time curve can be plotted.

[0064] like Figure 6 As shown, by observing whether the curve shows abrupt changes and what kind of changes, combined with the drill pipe condition and whether abnormal noises occur, abnormal drilling problems such as stuck drill bit, jammed drill bit, and drill bit suction during the drilling process can be identified. When the curve shows stable and constant stress, such as... Figure 6 Curve ① represents the normal drilling state; when the curve shows that the stress is stable in the early stage, then increases sharply and then decreases slowly, as shown in the figure... Figure 6 As shown in curve ②, the drill rod rotates normally, but when it suddenly extends a certain distance into the coal and rock mass axially, it is in a state of drill suction; when the curve shows that the stress is stable in the early stage, then decreases sharply and remains stable at a low level, such as... Figure 6 As shown in curve ③, if the drill rod rotates normally but cannot continue drilling into the coal and rock mass in the axial direction, it is in the top drilling state. If the drill rod stops rotating and there is obvious jamming noise, it is in the stuck drill state.

[0065] Based on the real-time pulverized coal quality-time curve, the range of pulverized coal output corresponding to the stable pulverized coal output velocity under normal drilling conditions is defined. Exceeding the limit of this range indicates a sharp change in pulverized coal output. Figure 7 As shown in fluctuation ①, the curve fluctuation pattern is characterized by a sharp increase followed by a slow decrease, which represents a sharp increase followed by a slow decrease in the amount of pulverized coal output. Figure 6 By observing the changes in the stress-time curve over time, and excluding drill bit anomalies such as stuck drill bit, jackknob failure, or other abnormal drill bit conditions, it can be determined that the drilled area is a stress concentration zone or a fractured coal and rock mass zone, which is prone to impact. Figure 7 As shown in fluctuation ②, the curve fluctuation pattern is characterized by a sharp decrease followed by a sharp increase, which represents a sharp decrease followed by a sharp increase in the amount of pulverized coal output. Figure 6 The curve changes over time, excluding drill bit abnormalities such as stuck drill, stuck drill, and top drill, indicate that there are large cracks in the area, and thus the distribution of cracks can be determined.

[0066] Example 2:

[0067] A real-time monitoring system for the weight of discharged pulverized coal based on drill cuttings method is disclosed. The structure is as described in Example 1, except that multiple wedge-shaped grooves 2 are arranged around the outer side of the front end of the drill bit 1. The depth of the wedge-shaped grooves 2 gradually decreases from the front end of the drill bit 1 to the rear end, allowing larger-diameter debris at the bottom to be lifted up. Irregularly arranged protrusions 4 are provided at the front end of the drill bit 1, which can thoroughly grind the drill cuttings during drilling.

[0068] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of this application, and these improvements and substitutions should also be considered within the scope of protection of this application.

Claims

1. A method for using a real-time monitoring system for the weight of discharged pulverized coal based on drill cuttings, comprising a real-time monitoring system for the weight of discharged pulverized coal based on drill cuttings, the monitoring system including a drill bit, drill rod, a pulverized coal collection telescopic cylinder, a pulverized coal collection fixed cylinder, a drilling rig, an air compressor, a pulverized coal collection monitoring system, and a control system, wherein, The drill rod is a hollow drill rod. One end of the drill rod is connected to the drilling rig, and the middle of the drill rod is connected to the bottom of the drilling rig through a drill rod clamping device. The other end of the drill rod is connected to the drill bit. An air compressor is connected to the outside of the drill rod. One end of the drill rod clamping device is connected to a dust collection and fixing cylinder through an L-shaped fixed connecting rod. The drill rod is installed inside the dust collection and fixing cylinder. Three telescopic tracks are evenly distributed on the inner wall of the dust collection and fixing cylinder. The dust collection and telescopic cylinder is slidably connected to the dust collection and fixing cylinder through the telescopic tracks. A coal dust collection and monitoring system is connected to the lower side of the dust collection and fixing cylinder through an air outlet pipe. The drilling rig, air compressor and coal dust collection and monitoring system are all connected to a control system. The drill bit has multiple air inlets connected to the drill rod around its middle section, and multiple powder outlet channels around its front end. The drill rod has a V-shaped groove track around its front end, and at least two support rods are symmetrically arranged inside the front end of the powder collection telescopic cylinder. The ends of the support rods are tapered and are located inside the groove track. The bottom of the rear end of the powder collecting telescopic cylinder is provided with a through rectangular slot. The rear end of the powder collecting fixed cylinder is provided with a circular inner wall through a limiting block. The limiting block matches the slot, and the outer diameter of the inner wall is the same as the inner diameter of the powder collecting telescopic cylinder. A drill hole for the drill rod to pass through is left on the inner wall. The coal dust collection and monitoring system includes a collection cylinder and a stress sensing device. A cylindrical stress sensing device is fixedly installed in the middle of the collection cylinder. An air outlet duct is connected to the outside of the collection cylinder above the stress sensing device. A filter screen is installed at the air outlet at the lower end of the collection cylinder. The method for using the above-mentioned real-time monitoring system for the weight of discharged pulverized coal based on drill cuttings is characterized by the following steps: (1) The air compressor and drilling rig are started, the drill bit contacts the coal seam borehole and begins to produce powder. The air blown out by the air compressor enters the borehole through the drill rod and drill bit. The gas is fully mixed with the coal powder generated during the drilling process to form a two-phase flow of air and powder. The two-phase flow of air and powder enters the air outlet pipe after passing through the powder collection telescopic cylinder. (2) The air-powder two-phase flow in the air outlet duct enters the coal powder collection and monitoring system. The air-powder two-phase flow blows directly towards the stress sensing device to obtain stress data. The Venturi flow meter in the air outlet duct monitors the gas flow rate. After passing through the stress sensing device, the air-powder two-phase flow enters the collection cylinder. The coal powder remains in the collection cylinder. The gas flows out after passing through the filter screen. The stress data and gas flow data are transmitted to the control system. After calculation, the stress-time curve and the coal powder mass-time curve are generated. The drilling status is determined by the stress-time curve. When the stress is stable and constant, the curve is a horizontal straight line, which indicates a normal drilling state. When the stress is stable and constant in the early stage, then increases sharply and decreases slowly, and the drill rod rotates normally, but suddenly extends a distance into the coal and rock mass in the axial direction, it is a stuck drill state. When the stress is stable and constant in the early stage, then decreases sharply and remains stable at a low level, and the drill rod rotates normally, but cannot continue drilling into the coal and rock mass in the axial direction, it is a top drill state. If the drill rod stops rotating and there is obvious jamming noise, it is a stuck drill state. Based on the real-time coal powder quality-time curve, the range of coal powder output corresponding to the stable coal powder output wind speed under normal drilling conditions is defined. Exceeding the limit of the coal powder output range indicates a sharp change in coal powder output. When the curve fluctuates by a sharp increase followed by a slow decrease, combined with the curve changes of the stress-time curve over time, and excluding drill bit abnormalities, it can be determined that the drilled area is a stress concentration zone or a coal and rock fracture zone, which has an impact tendency. When the curve fluctuates by a sharp decrease followed by a sharp increase, combined with the curve changes of the stress-time curve over time, and excluding drill bit abnormalities, it indicates that there are large fractures in the area, and the fracture distribution can be determined.

2. The method of using the real-time monitoring system for the weight of discharged pulverized coal based on the drill cuttings method as described in claim 1, characterized in that, The diameter of the drill bit's front end is larger than the diameter of the necked section at the rear end. The diameter of the drill bit's front end is the same as the outer diameter of the powder collecting telescopic cylinder. The end of the powder outlet channel passes through the necked section of the drill bit and is located inside the powder collecting telescopic cylinder.

3. The method of using the real-time monitoring system for the weight of discharged pulverized coal based on the drill cuttings method as described in claim 2, characterized in that, Multiple wedge-shaped grooves are arranged around the outer side of the drill bit front end, and the depth of the wedge-shaped grooves gradually becomes shallower from the drill bit front end to the rear.

4. The method of using the real-time monitoring system for the weight of discharged pulverized coal based on the drill cuttings method as described in claim 2, characterized in that, The drill bit has irregularly arranged protrusions at its front end.

5. The method of using the real-time monitoring system for the weight of discharged pulverized coal based on the drill cuttings method as described in claim 3, characterized in that, An annular blocking block is provided between the drill rod and the powder collecting telescopic cylinder. The blocking block fits against the inner wall of the rear end of the powder collecting fixed cylinder. A flexible rubber strip is provided between the front end of the powder collecting fixed cylinder and the powder collecting telescopic cylinder.

6. The method of using the real-time monitoring system for the weight of discharged pulverized coal based on the drill cuttings method as described in claim 5, characterized in that, A Venturi flow meter is installed inside the air outlet duct.

7. The method of using the real-time monitoring system for the weight of discharged pulverized coal based on the drill cuttings method as described in claim 6, characterized in that, In step (2), the steps for generating the stress-time curve and the pulverized coal quality-time curve are as follows: a. Stress data is directly acquired by the stress sensing device, and a stress-time curve is plotted with time as the horizontal axis and stress as the vertical axis. b. The calculation process for pulverized coal quality data is as follows: M =ρ×S×L (1) Where M is the mass of pulverized coal, S is the cross-sectional area of ​​the exhaust duct, ρ is the gas density, and L is the length of the duct through which the gas flows. R X =ρ×Q×V (2) In the formula, R X The stress is measured by the stress sensing device, ρ is the gas density, Q is the gas flow rate during the measured time period, V is the gas velocity, V=Q / S, and the gas density ρ is obtained from equation (2); L=V×t (3) The length L of the pipe through which the gas flows is calculated by equation (3). Substituting the gas density ρ and the length L of the pipe through which the gas flows into equation (1), the coal powder mass changing with time can be obtained, and a coal powder mass-time curve can be plotted.

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