193 results about "Soft Coals" patented technology

The invention discloses a gas extraction drilling track inversion and control system, and relates to the technical field of gas extraction, and the key points of the technical scheme are that the system comprises a high-gas coal seam rapid control elimination and reduction system and a gas injection flow increasing dynamic evaluation system; according to the rapid control elimination and reduction system for the high-gas coal seam, a method of combining experimental research, numerical simulation and on-site industrial tests is adopted, the coal seam gas occurrence rule of a working face of a Chengne mining area is obtained, the multi-component gas competitive adsorption rule of a three-soft coal seam is defined, and therefore gas injection driving key technical parameters of a coal seam gas abnormal target area are mastered; a gas injection drive gas-carrying rapid and accurate extraction technical system suitable for the gas abnormal area of the Chengne mining area is formed; according to the gas injection flow increasing dynamic evaluation system, working parameters are designed and monitored, the gas concentration is accurately monitored, and real-time detection and automatic early warning are achieved.

The invention relates to the technical field of coal mining equipment, in particular to a dual-power large-diameter inner deslagging wall protection type soft coal seam drilling device and a construction method thereof. According to the technical scheme, the drill bit comprises outer drill rods, a spiral inner drill rod, a pipe drill bit, a PDC drill bit and an inner rod body, a composite slice drill bit is arranged at one end of the pipe drill bit, the inner rod body is arranged in the pipe drill bit, the PDC drill bit located on one side of the slice drill bit is arranged at one end of the inner rod body, and multiple sections of outer drill rods are arranged on one side of the pipe drill bit. A plurality of sections of spiral inner drill rods located in the outer drill rod are arranged on one side of the inner rod body. By means of the large-diameter dual-power dual-channel inner deslagging structure, the problems of drilling in a soft medium layer, hole spraying, hole collapsing, drill holding and other serious phenomena are mainly solved, the hole forming rate is low, the hole drilling construction difficulty is large, coal holes can be subjected to wall protection, the deslagging efficiency is improved, and the hole forming rate is increased.

The invention discloses a method for rapidly and efficiently extracting coal mine gas in a broken and soft coal seam, and belongs to the technical field of coal seam gas development and coal mine gas prevention and control. According to the method, geological features of a coal mining planning area are determined, a ground U-shaped well and underground bottom-pumped rock drift layer-crossing drilling combined treatment system is deployed, and regional large-scale treatment is achieved in a well factory mode; the fracturing transformation range and the fracturing fluid distribution characteristics are detected by using a ground and underground combined micro-seismic monitoring and underground transient electromagnetic method, and the arrangement of layer-crossing drill holes is optimized; dividing the cross-layer drill holes into drainage holes and air exhaust holes, and formulating a collaborative extraction system in combination with different drainage and extraction stages; the method solves the problems that broken soft coal seam gas extraction is low in efficiency and long in period, and treatment blind areas exist, treatment time is remarkably shortened, cost is reduced, and safe and efficient production of a coal mine is guaranteed.

The utility model discloses a broken soft coal bed pneumatic airtight coring device which comprises a coring outer cylinder, a coring drill bit and an adapter. A pressing ball seat is arranged in the adapter, a locking mechanism core pipe is arranged in the lower end of the pressing ball seat in a sleeved mode, and the locking mechanism core pipe is further sleeved with a force storage mechanism body pipe capable of moving in the axial direction. The lower end of the power storage mechanism main body pipe is connected with the coring inner cylinder through a power storage mechanism main body pipe extension section capable of axially moving; a limiting step is arranged on the outer wall of the force storage mechanism body pipe, a locking sliding sleeve is further arranged outside the force storage mechanism body pipe in a sleeving mode, and a force storage spring is further arranged between the limiting step and the locking sliding sleeve in an abutting mode. A locking ball is embedded in the pipe wall of the lower end of the force storage mechanism body pipe and can axially limit the locking sliding sleeve. A sealing ball valve is arranged in the coring inner cylinder, and the pushing cylinder can be pushed by the locking sliding sleeve to move in the axial direction to close the sealing ball valve. The closed coring device solves the problems of hole spraying, hole collapse and the like when an existing closed coring device is used in a broken soft coal seam.

The present invention discloses a device and method for breaking coal, relieving pressure and increasing permeability by using a pneumatic flexible tool in a soft coal seam, which comprises: a drilling rig, in which a drill rod is installed, and the shaft of the drill rod is provided with an air flow cavity of a columnar structure, and the outer ring wall of the top end of the drill rod at the outermost end is provided with a partial thread; an air compressor pump, the output end of which is sealed and connected to the air flow cavity through a high-pressure air pipe; pneumatic slitting equipment, which comprises a pneumatic rotating device and a slitting device, the left end of the pneumatic rotating device is installed on the top end of the drill rod at the outermost end, and the right end of the pneumatic rotating device is installed with the slitting device, and the drill rod, the pneumatic rotating device and the slitting device are all coaxially arranged.

The invention discloses efficient broken soft coal seam while-drilling directional reaming and permeability increasing equipment and an implementation method, and relates to the technical field of coal mine drilling, the efficient broken soft coal seam while-drilling directional reaming and permeability increasing equipment comprises a drill rod, a drill bit, a flow guide assembly and a reaming assembly, the drill bit is arranged at the end of the drill rod, and the reaming assembly and the flow guide assembly are adjacently connected and fixed to the drill rod in a sleeving mode in the drilling direction; a distance is kept between the flow guide assembly and the drill bit; the broaching assembly comprises a crushing ring, an adapter sleeve, a through groove, crushing nails and a cutting tooth set, the multiple crushing nails are arranged on the end face, facing the drill bit, of the crushing ring, the adapter sleeve is fixedly arranged on the other end face of the crushing ring, and a through hole connected with the drill rod in a sleeving mode is reserved between the crushing ring and the adapter sleeve. A plurality of through grooves penetrating through the crushing ring and the adapter sleeve are evenly distributed outwards along the circumference of the through hole, the two cutting tooth sets are arranged in the circumferential direction of the crushing ring, and a slag passing notch is formed between the two cutting tooth sets.

The invention discloses a liquid nitrogen freezing and carbon dioxide blasting combined anti-reflection device and method. The device comprises a freezing pipe and an anti-reflection assembly. The anti-reflection assembly is mounted on the inner side of the freezing pipe; the anti-reflection assembly comprises a flexible air bag, an excitation device and a sealing positioning ring; the sealing positioning ring sleeves the outer side of the flexible air bag, and the flexible air bag is provided with an extension section; an end socket is mounted outside the sealing positioning ring in a sleeving manner, and the sealing positioning ring fixes the extension section on the end socket; the exterior of the end head is fixedly connected with the freezing pipe; the excitation device is arranged in the flexible air bag; and a firing line is mounted on the excitation device. The mechanical property of the coal body is optimized and improved through liquid nitrogen freezing, so that the mechanical strength of the coal body is enhanced, the brittleness is greatly improved, and then CO2 phase change blasting is performed to crack the coal seam; for a low-permeability soft coal seam, hole collapse caused by soft coal in single blasting is avoided, more cracks can be generated in the coal seam after CO2 blasting, the fracturing and permeability increasing effects are greatly improved, and a good promoting effect is achieved on gas extraction.

The invention discloses a soft coal rock stratum micro-nano rapid hardening early strength grouting reinforcement method considering working face mining-induced fracture making, and relates to the technical field of soft rock coal seam reinforcement. The method comprises the steps that drill holes are formed in a primary rock stress area in front of a working face, and a stress monitoring device is installed to monitor the change condition of mining-induced stress in real time; acquiring a mining law of the fracture rate; then, grouting holes are formed in the peak position of the mining-induced stress in advance, the optimal arrangement positions of the grouting holes and the distance between every two adjacent grouting holes are arranged according to the fracture development rule, and the depths and the diameters of the grouting holes are arranged according to coal rock stratum mechanical property evaluation; a grouting sleeve and a grouting valve pipe are arranged in the grouting hole; and finally, grouting is conducted, and after grouting is completed, the grouting reinforcement effect is evaluated. The soft coal rock stratum can be rapidly and effectively reinforced under the condition that mining-induced fractures exist.

The invention relates to the technical field of soft coal operation equipment, in particular to a measurement-while-drilling exploring tube with a flow and pressure measuring function, which comprises a tube body, a turbine flowmeter and a fluid pressure synchronizing component, the tube body can rotate around the axis of the tube body, the tube body is connected with a drilling tube, the drilling tube is connected with a rotating shaft of a directional drill, and the drilling tube is driven by the rotating shaft of the directional drill to rotate. And then the drilling pipe drives the pipe body to rotate, and fluid is conveyed into the pipe body from one end of the pipe body. According to the turbine flowmeter, the fluid pressure synchronization assembly is arranged, when fluid in the pipe body passes through the position where the fluid pressure synchronization assembly is located, the fluid pressure synchronization assembly enables the fluid in the pipe body and the pipe body to rotate at the same speed, and therefore an impeller in a measurement area of the turbine flowmeter is only pushed by the acting force of the fluid in the axial direction of the pipe body to rotate; therefore, the turbine flowmeter can accurately measure the flow velocity of the fluid in the pipe body, so that a worker can accurately and conveniently control the pump-out flow velocity of the pump according to the flow velocity of the fluid measured by the turbine flowmeter.

The invention relates to the technical field of coal mine gas extraction, and discloses a hole protecting device and method for a gas extraction drill hole. The hole protection device for the gas extraction drill hole comprises a first hole protection section and a second hole protection section, the first hole protection section comprises a first pipeline, an air bag assembly and a foldable suspension structure, and the suspension structure and the air bag assembly are both arranged on the outer wall of the first pipeline; the guide structure is arranged outside the first hole protection section in a sleeving mode so as to restrain the suspension structure and enable the suspension structure to be stored in the guide structure, and under the condition that the guide structure moves and exposes the suspension structure, the suspension structure is unfolded and clamped on the inner wall of a hole; the inflating device is communicated with the air bag assembly and used for inflating the air bag assembly, so that the air bag assembly is attached to the inner wall of the hole, and the hole is supported. In this way, a three-dimensional supporting system is formed by radial supporting force generated by expansion of the air bag assembly and axial anchoring of the suspension structure, and the hole collapse resistance of the soft coal seam is remarkably improved.

The utility model discloses an anchor rod supporting device for a soft coal roadway. The anchor rod supporting device comprises an anchor rod body, a grouting channel, a grouting opening, a base plate, a nut and a reinforcing structure. By arranging the reinforcing structure, when the anchor rod body is inserted into a hole of a soft coal roadway, the connecting pipe can be inserted into the hole together with the anchor rod body, and after the anchor rod body is inserted, the push head can abut against the tail end of the hole to push the push rod, so that the push rod slides into the connecting pipe; according to the anchor rod body, the inserting rod extends and slides towards the outer portion of the connecting pipe, the extending inserting rod can be inserted into a soil layer to be reinforced, the inserting rod can be filled with the inserting rod when cement mortar is injected, and therefore the firmness of the anchor rod body is improved, and the tensile capacity is improved.

The invention discloses a soft coal seam nanofluid fracturing propping material and a preparation method thereof.The soft coal seam nanofluid fracturing propping material is prepared from, by weight, 80-90% of a base material, 1-5% of a super-hydrophobic coating, 5-10% of a catalytic active component and 5-15% of a rheological enhancer, the base material is a compound of high-purity silicon dioxide nanoparticles and graphene nanosheets GNP, the particle size of the high-purity silicon dioxide nanoparticles is 50-200 nm, the super-hydrophobic coating is a fluorosilane modified layer, the thickness of the super-hydrophobic coating is 5-20 nm, and the invention relates to the technical field of coal bed gas exploitation. According to the soft coal seam nanofluid fracturing propping material and the preparation method thereof, the surface of the material is provided with a super-hydrophobic coating, friction force with a coal matrix is reduced, high embedding resistance is achieved, the flow conductivity is specifically enhanced, an extra flow channel is provided through a porous nanostructure, the fracturing fluid permeability is improved, and meanwhile gas desorption can be cooperated; catalytic active sites are introduced to the surface of the material to promote adsorption and diffusion of methane molecules.

The invention relates to the technical field of coal seam gas extraction, in particular to a gas extraction method for a soft and hard coal composite area. In the drilling and production process, drilling cuttings and drilling machine mechanical parameters along with the coal seam; soft and hard coal area demarcation and characteristics are dynamically discriminated, and spatial interpolation and three-dimensional geological modeling are carried out in combination with the drilling spatial position; the boundary radiuses of the soft coal area, the hard coal area and the transition area of the soft coal and the hard coal are obtained through calculation, permeation increasing measures are arranged for drilling operation of the corresponding coal seam areas respectively, and hydraulic measure parameters are adjusted; and observing to obtain the fracture expansion range and the size of the cavity, and performing gas extraction when the conditions are met. According to the method, the gas extraction effect of the different coal seam composite area is improved by dynamically recognizing the soft and hard coal areas and combining the areas with precise gas treatment. The method can guide actual gas extraction engineering in the underground coal mine field, and is of great significance to the related fields of carbon sequestration, coal bed gas development and mine gas control.

The invention provides a high-quality cross-boundary continuous grading support system suitable for a soft coal rock roadway in a complex environment, which relates to the technical field of coal mine roadway support and comprises a first-stage foundation support system, a second-stage reinforced support system and an intelligent monitoring system, the first-stage foundation support system, the second-stage foundation support system and the third-stage foundation support system cooperate with one another to achieve continuous graded support and long-time stable control of roadway surrounding rock, and the first-stage foundation support system is used for achieving surrounding rock shallow constraint, preliminary stress release and preliminary rock mass consolidation; through continuous cooperative control of first-stage foundation support and second-stage reinforced support and application of a novel support material, rheological and swelling deformation of surrounding rock can be effectively restrained, and practical application verifies that side deformation and top deformation of a roadway are reduced, and the bulging amount of a bottom plate is controlled within safety limit values; through the design of lagging grouting full anchoring and collaborative anchoring, fractured rock mass is effectively consolidated and repaired, the stress concentration degree of surrounding rock is improved, and the problem that an existing support is poor in long-term stability is solved.

The invention relates to the technical field of coal mine gas control and CO2 geological storage, and particularly discloses a soft coal seam dynamic fracture self-adaptive CO2 displacement-anti-reflection integrated system which comprises a dynamic fracture monitoring unit, a CO2 collaborative anti-reflection unit, a self-adaptive regulation and control unit and a safety protection unit. The dynamic fracture monitoring unit is used for capturing coal seam fracture development dynamics and gas injection process parameters in real time; the self-adaptive regulation and control unit is in communication connection with the dynamic fracture monitoring unit, and the CO2 synergistic anti-reflection unit is in control connection with the self-adaptive regulation and control unit and is used for realizing CO2 enhanced anti-reflection displacement; the safety protection unit is used for guaranteeing system operation safety. According to the method, real-time adaptation of the coal seam fracture state and the injection-production parameters is achieved, the problems that in a traditional fixed parameter mode, the displacement efficiency attenuation is fast, and the coal body stability is poor are solved, the CH4 recovery rate and the CO2 storage rate are increased, and the safety and high efficiency of soft coal seam gas control operation are guaranteed.

The invention discloses a design method of a high-performance grouting material accurately matched with a soft coal rock physical property structure, and relates to the technical field of geotechnical engineering grouting. According to the method, mineral components, permeability, fracture distribution, strength, wettability and hydrological characteristics of soft coal rock are analyzed through multi-dimensional tests such as X-ray diffraction and a scanning electron microscope, and a quantitative mapping relation between physical property parameters and grouting material performance is established; constructing a grouting reinforcement material database comprising a material sub-library, a performance sub-library and a case sub-library, and introducing a generative adversarial network to dynamically update the fracture model; an orthogonal test and a machine learning algorithm are adopted to carry out multi-objective ratio optimization, and precise matching of grouting material performance and engineering geological conditions is realized in combination with field adaptability index closed-loop verification. According to the method, the grout groutability and the surrounding rock deformation control effect can be remarkably improved, the technical problems that a traditional grouting material depends on experience, and a database is static and low in efficiency are solved, and an intelligent solution is provided for complex soft coal rock engineering reinforcement.

The invention discloses a device and method for preventing soft coal seam gas extraction drill hole deformation and hole collapse, and relates to the technical field of coal seam gas extraction, the device comprises an anti-collapse mechanism used for ensuring the accuracy and controllability of the reinforcing range and effectively preventing invalid slurry loss, and the anti-collapse mechanism comprises a hole protection sleeve unit, a connecting unit and a bag unit; the bag unit is arranged on the outer side of the connecting unit and comprises a stacked bag installed on the outer side of the stacked casing pipe through the connecting unit, a bottom bag is installed on the outer side of the bottom casing pipe through the connecting unit, and high-strength grout is injected into the bag unit through a high-pressure grouting pump, so that the stacked bag and the bottom bag expand in a drill hole to fill surrounding cracks; and the invalid diffusion path of the slurry is blocked, targeted reinforcement of the soft coal seam is achieved, the problem that the slurry is lost along the maximum crack channel in traditional grouting is solved, the stability of the gas extraction drill hole is remarkably improved, and the service life of the gas extraction drill hole is remarkably prolonged.

The broken soft coal seam top and bottom plate double-layer horizontal well ground coal extraction pressure relief extraction system comprises a top plate horizontal well and a bottom plate horizontal well, and the top plate horizontal well comprises a top plate horizontal well first opening, a top plate horizontal well second opening and a top plate horizontal well third opening horizontal section main branch which are sequentially connected; the top plate horizontal well branches are obliquely arranged below the three-opening horizontal section main branch of the top plate horizontal well, and caves are formed in the top plate horizontal well branches; the bottom plate horizontal well comprises a first bottom plate horizontal well opening, a second bottom plate horizontal well opening, a third bottom plate horizontal well opening horizontal section main branch and a plurality of bottom plate horizontal well branches obliquely arranged above the third bottom plate horizontal well opening horizontal section, wherein the first bottom plate horizontal well opening, the second bottom plate horizontal well opening and the third bottom plate horizontal well opening horizontal section main branch are sequentially connected. And each top plate horizontal well branch is communicated with one bottom plate horizontal well branch through one cave. The device can quickly release pressure or does not need to release pressure, can quickly discharge and extract after being put into operation, and realizes quick gas seeing and gas production peak.

The soft coal seam punching while drilling and retreating type slotting integrated drill bit comprises a punching assembly and a sealing assembly, the punching assembly comprises a drill bit and a tailstock, a first water guide pipe is arranged at the tail of the drill bit, a first end socket is connected to the tail of the first water guide pipe, a first water guide hole is formed in the first end socket, and a second water guide hole is formed in the tail of the first water guide pipe; the head of the drill bit is provided with a water spraying hole communicated with the first water guide pipe, a flow collecting cavity is formed in the tailstock, the tail of the flow collecting cavity is connected with a water inlet pipe, the head of the flow collecting cavity is connected with a second water guide pipe, and the drill bit is connected with the tailstock through a straight rod. The sealing assembly comprises ring sleeves installed on the second water guide pipe and the first water guide pipe respectively, sealing bags and bag filling mechanisms used for controlling the sealing bags are installed on the ring sleeves, and a slotting assembly is arranged between the two ring sleeves.

The application discloses a soft coal seam acoustic wave penetration method, comprising the following steps: sampling the rock of one side rock stratum of the soft coal seam to be penetrated, obtaining the tensile strength and shear strength of the rock, the one side rock stratum being the coal seam roof or the coal seam floor; drilling a working borehole in the one side rock stratum; implementing impact in the working borehole; the impact wave generated by the impact cracks the rock stratum around the working borehole, the impact wave cracks the rock stratum, and the acoustic wave is formed after the impact wave attenuates, the acoustic wave is used for penetrating the soft coal seam, wherein the stress wave pressure entering the soft coal seam is lower than the tensile strength and shear strength of the rock. The application solves the problems that it is difficult to develop an effective high-strength sound source capable of being loaded to the coal seam and it is difficult to implement drilling in the soft coal seam in the prior art. The application converts the strong impact into high-strength acoustic wave by using the coal seam roof or the coal seam floor rock stratum, the high-strength acoustic wave is used for penetrating and exciting the coal seam, and the required acoustic wave can be obtained, and the gas desorption is promoted.

The present application relates to the technical field of soft coal seam drilling, and discloses an intelligent control drill rod and blowout hole device for soft coal seam drilling, which comprises a front-end sensing unit, a relay sensing unit, a hydraulic servo motor, a frequency converter, a shape memory alloy framework, a thermal-responsive polymer expansion gel layer and a control unit. The device can expand to 3 times the original diameter within 2 seconds through thermal triggering, forming a multi-stage labyrinth seal. The control unit is installed with an embedded AI chip to run an LSTM pressure time sequence prediction model, and combines temperature and vibration multi-source data fusion to judge the blowout risk level, solving the problems of lack of real-time gas pressure dynamic monitoring capability of traditional drill rods, reliance on artificial experience to judge blowout risk, and response lag. The single position pressure sensor is easily disturbed by local rock layer mutation, has a high false alarm rate, and cannot distinguish between normal pressure fluctuations and blowout precursors, so the device realizes early blowout warning and actively suppresses blowout accidents.

The utility model relates to the technical field of coal mine drilling coring, in particular to a novel closed coring device. Comprising an outer barrel, a drill bit and a drilling tool connector, the drill bit is located at one end of the outer barrel, the drilling tool connector is located at the other end of the outer barrel, a spear mechanism is installed at the end, away from the drill bit, of the outer barrel, a hanging mechanism is installed in the outer barrel and located at one end of the spear mechanism, and a ball seat is arranged in the outer barrel and located on one side of the hanging mechanism; an inner cylinder is arranged in the outer cylinder and located on one side of the ball seat. According to the novel closed coring device, rope coring is achieved through cooperation of the outer barrel, the drill bit, the spear mechanism, the suspension mechanism, the ball seat and the closed ball valve, after closed coring of a broken soft coal core is completed, other parts except for the outer barrel, the drill bit and a drilling tool connector are directly taken out through the male fishing head, time cost is saved, and working efficiency is improved. And meanwhile, when the coring device is used, core clamping can be effectively avoided, and the sealing reliability is improved.

The invention discloses a gas graded reinforced extraction method based on the full life cycle of a horizontal well. The gas graded reinforced extraction method comprises the steps that basic occurrence information parameters and gas data of a target coal seam are obtained firstly; constructing a brittle-soft index and evaluating the target coal seam by integrating longitudinal and transverse wave velocity data obtained by logging of the target coal seam; if the coal body is the soft coal body, a horizontal well sectional type hydraulic punching construction scheme is formulated; if the coal body is a brittle coal body, a horizontal well sectional type hydraulic fracturing construction scheme is formulated; horizontal wells and vertical wells are constructed according to corresponding schemes; then, according to the corresponding construction scheme, the horizontal well is divided into sections through packers; after construction is completed, gas drainage is conducted on the horizontal well and the vertical well; in the gas drainage and mining process, the LSTM model is used for predicting and evaluating the future gas drainage and mining trend; if the gas drainage and mining data is in a remarkable descending trend, the supercritical CO2 is injected into the target coal seam in a pulse mode, the gas drainage and mining efficiency is effectively improved, and efficient gas drainage and mining of the horizontal well in the whole life cycle are achieved.

The utility model relates to the field of drilling equipment for soft coal seams, in particular to a sealing structure for a through cable drill rod core joint, which comprises an annular sealing groove, the annular sealing groove comprises a mounting part and a pressure relief part, a sealing piece is sleeved in the mounting part to ensure the sealing performance of the butt joint of an inner joint and an outer joint, and the pressure relief part is arranged on the adjacent side of the mounting part. The mounting part is positioned on the reverse side of the inserting direction; the pressure relief part comprises a deformation containing groove and a pressure relief groove, the deformation containing groove is axially arranged and used for containing the axial deformation of the sealing piece, the pressure relief groove is formed in the bottom face of the deformation containing groove, and the pressure relief groove structure should guarantee that when the sealing piece deforms and enters the pressure relief part, sealing failure is caused by the fact that the radial size of the position where the pressure relief groove is located is increased. In addition, an axial pre-jacking protrusion is arranged at the position, corresponding to the pressure relief portion, of the installation portion, and the sealing piece has initial elastic tension due to the arrangement of the pre-jacking protrusion.

The utility model discloses a soft coal seam gas extraction drilling hole protection device, which relates to the technical field of coal mining, and comprises two bases, the upper surfaces of the two bases are fixedly connected with a U-shaped plate together, a moving plate is arranged below the U-shaped plate, an adjusting mechanism is arranged between the moving plate and the U-shaped plate, and the adjusting mechanism is connected with the U-shaped plate. The moving plate moves through an adjusting mechanism, and the upper surface of the moving plate is fixedly connected with a first motor. The protection pipe is installed on the lower surface of the movable plate, then the movable plate is moved downwards, so that the protection pipe can be moved to the underground in the drilling process, when the protection pipe is about to sink into the ground, the protection pipe is detached, then the movable plate is moved upwards, and then a new protection pipe is installed again. And the new protection pipe is pressed above the protection pipe in the ground, so that a protection pipeline can be formed by repeatedly utilizing a plurality of protection pipes.

The utility model discloses a top coal caving hydraulic support for a soft coal seam, and relates to the technical field of hydraulic supports. The top coal caving hydraulic support for the soft coal seam comprises a hydraulic support structure, the bottom end of the hydraulic support structure is movably connected with a movable base, and an adjusting type traction device is fixedly installed at the top end of the movable base; according to the top coal caving hydraulic support for the soft coal seam, by arranging an adjusting type traction device, a U-shaped plate can be driven by an extension rod to vertically slide on the outer side of a driving box, the U-shaped plate is promoted to drive a traction head to conduct height adjustment, and then height locking can be conducted on the extension rod through a gear ring in cooperation with distance adjustment of a movable rack and a fixed rack; the traction head is positioned after height adjustment, so that the support can be adjusted according to the actual traction height of field traction equipment, normal traction of external traction equipment is guaranteed, and the withdrawing efficiency of the support is improved.

The invention provides a crushed soft coal and gas co-mining method based on underground coal extraction and pressure relief, and belongs to the technical field of coordinated development of coal and coal bed gas. Stress of a coal rock layer is effectively released through pressure relief extraction of a cross-layer coal extraction drill hole and a bedding coal extraction drill hole, coal bed gas extraction of a coal bed is promoted, and the coal bed gas extraction efficiency is improved. The hole sealing effect is improved through multiple times of slurry supplementing of the inorganic material, the extraction amount of underground coal bed gas is increased, and therefore co-extraction of crushed soft coal and coal bed gas is achieved.

The invention discloses a self-adaptive hole protecting and sealing device and method for soft coal seam gas extraction drilling, the device comprises a sectional type screen pipe, an active hole protecting assembly and a hole sealing assembly, the active hole protecting assembly comprises a multi-section type center hollow rod, a cable and a dynamic hole protecting supporting array; the dynamic hole protection supporting array comprises a supporting unit which stretches out and draws back in the radial direction of the multi-section type center hollow rod, and the supporting unit is used for actively supporting the drilling hole wall and adjusting the supporting force in a real-time and self-adaptive mode. Through a dynamic sensing-active regulation-cooperative sealing closed loop mechanism, the defect of separation of static passive sealing and hole protecting and sealing is overcome. The network distributed electric push rod carries a sensor to monitor hole wall changes in real time, supporting force is independently adjusted, and real-time dynamic hole protection is achieved. And the automatic liquid supplementing cavity is matched with the double-back-pressure valve to automatically maintain the sealing pressure. Hole protecting and hole sealing are in two-way coupling linkage, dynamic sensing and real-time self-adaptive adjustment can be achieved, effective sealing of a drilled hole can be maintained all the time, and organic unification of active hole protecting and hole sealing can be achieved.

The utility model relates to the technical field of coal mining, especially relates to a soft coal seam drilling hole wall stability reinforcing device, including the drill rod installation head, the outer surface of drill rod installation head is provided with the first outer thread, the rear end of drill rod installation head is fixedly connected with the guide assembly, the outer surface front part of guide assembly is fixedly sleeved with the grouting assembly, the outer surface middle part of guide assembly is movably sleeved with the support reinforcing assembly. The utility model discloses a soft coal seam drilling hole wall stability reinforcing device, through inflatable rubber support ring inflation, makes it swell and lets the embedding convex head embeds the hole wall, and the pre-support is formed quickly, and then the slurry is injected into the guide sleeve, and the slurry flows out from the annular array distribution slurry outlet hole and penetrates the coal seam fracture, and the inflatable rubber support ring and the solidified slurry jointly reinforce the hole wall, greatly improve the hole wall stability and the anti-deformation ability, guarantee the safety of soft coal seam drilling operation.

The invention relates to the technical field of coal mine safety engineering, in particular to water injection equipment and a water injection method for a strong-adhesion difficult-to-wet three-soft coal seam. The equipment systematically integrates a water injection pressure adjusting device, a moistening agent adding device, a water injection monitoring device and a protection device. According to the invention, by constructing a closed-loop feedback intelligent water injection system, the technical bottlenecks of poor water injection wettability, non-uniform water transverse dispersion and sweating or water leakage caused by easy plastic deformation of the coal wall due to complex coal body pore structure and low surface free energy in the strong-adhesion and difficult-to-wet three-soft coal seam are effectively solved; the dust falling efficiency and the engineering reliability of coal seam water injection are remarkably improved, and meanwhile the synergistic enhancement effect on coal mine rock burst prevention and control is achieved.