34results about How to "Shorten prepumping time" patented technology

The invention relates to a directional hydraulic pressing penetration, permeability increase and outburst elimination method of a guide groove, which comprises the steps of (1) constructing a guide groove drill or the guide groove drill and control drills in a coal seam; (2) forming a guide groove in the guide groove drill in advance; (3) utilizing the guide groove drill or the control drills to perform hydraulic fractures, utilizing the guide groove and the control drills to perform directional control on the hydraulic fractures, enabling the coal body between the guide groove drill or the guide groove drill and the control drills to be pressed into penetration, forming multiple fractures among drills, and enabling a large amount of nickings to be brought out through the high-pressure water; and (4) after the fractures finish, enabling all the drills to be sealed and accessed into a drainage system, and beginning extraction. By means of the method, the number of pressing penetration of drills can be increased by 50%, the pressure relief scope of the coal seam is increased by over one time, the permeability of the coal seam is remarkably improved, gas extraction is increased by more than four times, measure drills can be reduced by about 60%, fore-pumping time is effectively reduced, area outburst elimination is achieved, and gas hazards can be reduced to the largest extent.

An anti-collapsing drilling method for grout spraying of a soft coal seam includes the following steps that first, an anti-collapsing drilling device for grout spraying of the soft coal seam is machined and tested; second, technological parameters of the anti-collapsing drilling device for grout spraying are designed; third, hole reinforcing grout is prepared, and the solidification property of the grout is tested; fourth, the anti-collapsing drilling device for grout spraying of the soft coal seam is installed; fifth, anti-collapsing drilling for grout spraying is performed; sixth, drilling stops till the designed depth is achieved, clean water is used for cleaning a grout spraying pipeline and a spray nozzle, and a drill stem and a drill bit are withdrawn. Due to the adoption of the method, the efficiency for drilling bedding holes in the soft coal seam is substantially improved, the hole forming rate for drilling holes in 100 meters is substantially increased, and time for drilling the bedding holes in the soft coal seam is shortened; the gas drainage efficiency of the bedding holes in the soft coal seam is substantially improved, and time for gas pre-drainage of the soft coal seam is greatly shortened; the probability that gas exceeds the limit is greatly reduced in the tunneling and stoping period, and valuable time and a safety guarantee are provided for safe and efficient stoping and tunneling of a coal mine.

The invention discloses a low-air-permeable coal bed static blasting anti-reflection gas extraction method. Multiple roof bedding drill holes are constructed along the coal bed top plate, the drill holes are filled with silent breakers which are subjected to a hydration reaction to generate radial compressive stress and tensile stress to hole walls, when the tensile stress exceeds tensile strengthof coal bed roof rock, the coal bed roof starts to generate cracks, that is to say, a gas migration and output passage is built in the coal bed roof rock, the roof bedding drill holes are subjected to repairing, hole sealing and networking extraction, and coal bed gas is extracted indirectly. Meanwhile, a group of coal bed bedding drill holes are constructed in a coal bed, and migration of the coal bed gas to the roof bedding drill holes is accelerated. After it is determined that extraction reaches the standard, progressive cover type tunneling is conducted, and finally rapid tunneling of alow-air-permeable coal bed coal rod is achieved. Accordingly, by conducting static blasting fracture on the roof bedding drill holes, the gas migration and output passage is built in the coal bed roofrock, and the extraction amount and extraction rate of the low-air-permeable coal bed gas are increased.

The invention provides a progressive shielding type gas depressurizing extraction method which is particularly suitable for depressurizing outburst elimination extraction of coal roadway strip gas in a soft high-outburst coal seam through seam-penetration drilling holes. The seam-penetration drilling holes are constructed in the portions, on the two sides of an upper coal roadway, of the coal seam from a base plate roadway. Since the high-gas-outburst coal seam has high outburst tendency, the depressurizing permeation increasing measure of direct drilling hole construction can cause severe disturbance to an original coal body to induce a hole jetting phenomenon, the coupling mode of common drilling holes and punching and cutting drilling holes under the condition of base plate seam penetration is built, and the drilling holes are divided into the partition holes, the shielding holes and the depressurizing holes. Through reasonable arrangement of the common seam-penetration drilling holes and the drilling, punching and cutting drilling coupled depressurizing drilling holes, the gas extraction effect of the area coal body is improved, the phenomena of an outburst elimination blanking zone and hole jetting are voided, the drilling construction speed in remarkably increased, and the gas extraction effect is remarkably improved, and the technology has good adaptability to all coal seams of different occurrence states.

The invention provides a positive pressure and negative pressure combined gas drainage process by pressurizing a coal body of a thick coal seam. The process comprises the following steps of: 1) arranging and drilling holes: selecting drilling distances, array pitches, angles, hole diameters and hole lengths according to the occurrence situation and the drainage radius of a coal seam to be subjected to drainage; 2) carrying out drilling construction and sealing holes: determining angles and directions of a drilling machine to carry out the drilling construction to keep the stability of the drilling machine in a construction period; and sealing the holes after the drilling is finished; 3) injecting water into the coal body and pressurizing: pressurizing the water and injecting into the coal body to fill cracks in the coal body; and 4) carrying out gas drainage: carrying out the gas drainage after carrying out the drilling construction, sealing the holes and stabilizing, and injecting the water into the coal body and pressurizing. With the adoption of the process disclosed by the invention, the gas drainage effect is greatly improved, and the pre-drainage time of gas is greatly shortened, so that the exploiting time of coal is correspondingly increased; and meanwhile, the drainage efficiency is high, the gas concentration in an air flow in a production period is low, an over-limit alarming phenomenon is avoided, and the production efficiency is improved.

A vacuum storing and testing device for transmission electron microscope sample rods belongs to the field of transmission electron microscope vacuum fittings. In storage of the sample rods, energizing testing and heating testing can be performed on the sample rods. The device comprises the components of a movable frame, a vacuum pump system, a vacuum measuring-and-displaying system, a vacuum cap, a valve system, a sample rod storing assembly and a plug. The device realizes simultaneous storage of multiple sample rods and is provided with an adding window which is reserved. The device can pump the air pressure in a chamber from atmosphere pressure to 4*10<-4> Pa within five minutes, and a limit vacuum pressure can reach 5*10<-5> Pa. The vacuum storing and testing device has advantages of effectively preventing electron microscope pollution caused by pollution or erosion by the sample rods in placement at outside, greatly reducing pre-pumping time of the sample rods in the electron microscope, realizing higher speed in reaching a stable vacuum degree of the electron microscope and prolonging service life of the sample rods. The vacuum storing and testing device further realizes benefits of convenient operation, high vacuum degree, easy adding of sample rod storing stations, and high suitability for different types of transmission electron microscope sample rods.

The invention provides a slotting and fracturing cooperation networking permeability increasing method for a low-permeability coal seam, which is applicable to regional gas control for high-gas-content low-permeability coal seams. The permeability increasing method comprises the following steps that: firstly, hole positions of slotting drill holes and fracturing drill holes are arranged alternately at a floor suction roadway in a networking arrangement mode; each slotting drill hole is subjected to high-pressure water jet flow slotting to form an annular slotted hole; and then, each fracturing drill hole is subjected to segmented fracturing, and a fracture net is formed in the coal seam. The slotting drill holes and the fracturing drill holes are in cooperative arrangement; the slotted holes formed by slotting are used for controlling the expanding direction of fracturing cracks; the number of cracks in the coal seam can be effectively increased through segmented fracturing multiple times; and good conditions are created for the drill hole gas extraction and the gas flowing in the coal seam. After the fracturing cracks are communicated with the slotted holes, a crack network is formed in the coal seam; the permeability coefficient of a coal body around the drill holes can be improved by 150 to 400 times; the single-drill-hole gas extraction effective influence range can be expanded by 2 to 4 times; the drill hole gas extraction quantity can be increased by 3 to 6 times; and the gas pre-extraction time in the high-gas outburst coal seam can be effectively shortened.

The invention relates to a coal seam pre-splitting method based on gas extraction, which adopts a 'CO2 gas extraction device' as a tool to blast and pre-split a pre-mined coal seam, so as to increase the crack of the coal seam, drive out gas absorbed on the coal seam and extract the gas. The method particularly comprises the following steps: drilling a hole on the working surface of a pre-mined coal seam, filling CO2 gas extraction device into the drilled hole, sealing the drilled hole, detonating the CO2 gas extraction device, releasing high-pressure CO2 gas for deep-hole impact and pre-splitting of the coal seam, taking out the CO2 gas extraction device, and connecting the drilled hole with a gas extraction system to extract gas. The pre-splitting method of the invention can greatly enhance the permeability of the coal seam, promote the gas dissociation in the coal seam, and improve the underground gas extraction efficiency of the coal mine.

The invention provides a gas control method for a large-mining-height working face of a high gas coal seam, and belongs to the technical field of safety of mines. The gas control method comprises the steps of arranging a first bed extraction tunnel during excavating at the working face; upwards arranging a crossing hole through the first bed extraction tunnel to pre-extract gas; arranging and cutting holes in the bed extraction tunnel to pre-extract gas; arranging an inclined connection roadway to form a ventilation circuit; arranging a second bed extraction tunnel and a connection roadway; pre-extracting gas through the crossing hole which is upwards arranged through the first bed extraction tunnel; arranging a high extraction tunnel to reach a gob caving slit band; arranging the crossing hole in the high extraction tunnel; pumping gas at the high extraction tunnel. According to the gas control method for the large-mining-height working face of the high gas coal seam, gas pumping drilling holes are arranged in each tunnel, a gas treatment scheme under the combination of the bed extraction tunnel, the high extraction tunnel and the current coal seam extraction is created, and therefore, the gas emission rate in the excavating and recovery periods at the working face can be effectively reduced, the continuing speed of recovery at the working face is raised, the gas accumulated at the working face and upper corners and ultralimit of gas can be effectively avoided, and as a result, the safety in production at the working face can be ensured.

The invention discloses a method for uncovering coal in a stone gate of a gently inclined extra-thick coal seam, which is especially suitable for protruding dangerous coal seams with a small inclination angle and a large thickness in a coal mine. When the Shimen is excavated to a vertical distance of 12m from the coal seam, excavate an inclined stone gate on the right side of the Shimen, and when the inclined stone gate is excavated to a vertical distance of 7m from the coal seam, a floor roadway is excavated in front of the Xieshimen. The floor roadway is parallel to the Shimen and excavated along the coal seam . A plurality of drilling sites are evenly arranged in the completed floor roadway, and the coal seam gas is pre-extracted by hydraulic slotting drilling from the drilling site to the coal seam. After the gas drainage reached the standard, Shimen resumed excavation in the original direction, and passed through the coal seam and entered the roof 2m to complete the coal uncovering work. Through the construction of the floor roadway, the present invention transforms the slow-sloping long drilling that restricts the speed of uncovering the coal into the floor-penetrating drilling, which breaks the bottleneck problem of slow coal mining in the gently inclined and extra-thick coal seam, and realizes safe and fast coal mining, which has a wide range of applications. practicality.