36results about How to "Increase free surface" patented technology

The invention relates to a multi-row micro-differential roadbed deep hole blasting construction method, which comprises the following steps of: (1) selecting blasting parameters; (2) calculating security; (3) arranging a stair and a free face; (4) distributing holes and drilling holes; and (5) blasting. The blasting method is a multi-row deep hole millisecond micro-differential blasting method; and the blasting is performed by pull trough blasting and side slope blasting in a roadbed sequentially, wherein the pull trough blasting is loose blasting and the side slope blasting is precraking blasting. In the method, a shock conducting tube non-electric priming system micro-differential control blasting technology, a comprehensive blasting construction scheme of loose blasting, the deep hole millisecond micro-differential blasting technology and the roadbed side slope precraking blasting technology, and a wide-pitch and low-resistance hole distribution mode are adopted, so that explosivesand detonators are saved, the drilling mechanization degree is enhanced, the labor cost is reduced, the blasting effect is enhanced, the large rate of blast rocks is reduced, the material abandoning rate is reduced and harms of blasting vibration, impact waves, flying stones and the like are reduced; furthermore, when the blasting effect is enhanced and the stability of the blast roadbed side slope rocks is guaranteed, the absolute safety of blasting can be guaranteed.

The invention discloses a method for hard roof advanced precracking control caving in a coal mine stope, and belongs to the technical field of coal mining, and particularly relates to a hard roof advanced precracking control caving method for determining parameters of borehole layout, such as, the pore opening positions, the depth of drilling holes, the angle of the drilling holes and numbers of the drilling holes of hard roof advanced precracking drilling in the coal mine stope and calculating the explosive payload of the drilling holes. According to the characteristics of hard roof fracture,five blast holes in a fan shape are formed to form a fixed angle; the middle portion and the end of the a working face which are most difficult to break of the hard roof can be effectively pre-cracked, so that the roof can collapse as required; based on the characteristics of blasting, the blasting sequence of the blast holes from the middle portion of a cutting hole to both ends can maximize thefree surface of the blasting and reduce the explosive payload, and the operation is convenient; and a calculation formula of the explosive payload of the hard roof of preceding loosening blasting indeep hole is given quantitatively to enable the control of hard roof to be more scientific, quantitative, accurate and simple.

The invention discloses a millisecond blasting vibration and flying rock control method. The millisecond blasting vibration and flying rock control method includes the following steps of 1), design ofa blasting scheme; 2), hole stepping and drilling; 3), powder charging; and 4), blasting, wherein detonator blasting is delayed through milliseconds, partition blasting is adopted in a blasting sequence, a first region close to an external building is blasted firstly, then a second region away from the external building is blasted, according to the blasting sequence of each region, cutholes are blasted, tunneling holes are blasted, then periphery holes are blasted, finally, bottom holes are blasted, the delay time of the cutholes is controlled to be set at 60 milliseconds-100 milliseconds, the delay time of the tunneling holes is set at 600 milliseconds-750 milliseconds, and the delay time of the periphery holes is set at 950 milliseconds-1,150 milliseconds. The control method is good inblasting effect, high in precision and good in safety.

The invention provides a horizontal segment blast cracking and chemical weakening method for igneous rock in a thick coal seam. The method comprises the following steps: forming water injection drilling holes and a plurality of V-shaped grooves on one sides, close to working surfaces, of a tail entry and a haulage entry; carrying out a sampling test on the igneous rock, configuring a corresponding chemical solution, and determining the concentration, solution injection volume and solution injection time of the chemical solution; and then carrying out charging, stemming and sealing, and connecting a detonating cord for blasting. According to the invention, a physical method and a chemical method are combined, so that the general problem of difficult pushing of the igneous rock in the coal seam of the existing coal mine is solved; and the process is simple, the cost is low, the benefit is good, and the safety production of the coal mine is realized to the maximum extent.

The present invention provides a cutting method combining deep hole cutting and small well cutting, and belongs to the technical field of ore belt mining. The invention adopts a cutting process combining deep hole cutting and small well cutting, not only cancels the roadway cutting, simplifies the cutting process, and reduces cutting cost significantly, but also provides an experimental basis to realize cutting of deep hole cutting blasting, and has strong promotion and application value. Medium-length holes on both sides of the small well are cut by dual radiation center construction. Taking the small well as a free surface, delay blasting is performed from small well center to the two sides to realize medium-length hole blasting pull trough without roadway cutting, and blasting initial free surfaces are created for follow-up blasting of medium-length hole breaking ground. The long axis direction of a cutting well is perpendicular to the row surface of the cutting deep hole, and the length direction is greater than the row spacing of the cutting deep hole, therefore the deep hole blasting gets the maximum free surface, greatly enhancing the blasting success rate which can reach 100%.

The invention relates to the technical field of coal mine rock roadway excavation, in particular to a mechanical rock breaking method for a coal mine rock roadway. The method includes the following steps that S1, at least one drilling region and the location of each hole are selected on the excavating face of the roadway; S2, drilling operation is performed in the drilling region so as to form a new free face in rock; S3, impact type rock breaking operation is conducted on rock in the drilling region so as to form a sunken region; S4, by using the sunken region as a starting point, impact typerock breaking operation is conducted outward gradually to the edge of the excavating face. By means of pre-opening, the free face of rock mass is increased, the integrity of the rock mass is destroyed, the difficulty of impact type rock breaking is reduced, and the speed of roadway excavation is greatly increased; the drilling operation is completed by mechanical equipment, the operation speed ishigh, the work efficiency is improved, and labor and material resources are effectively saved.

The invention discloses a cutting blasting method suitable for excavation of a high-plastic low-strength rock tunnel. The cutting blasting methodis improved from reducing the distance between cuttingholes and changing charging structures of the cutting holes, the distance between the cutting holes is reduced to ensure that the explosion stress wave energy generated by explosives is much higher than the energy required for plastic deformation of plastic rock mass during the explosion, and in addition, the design of auxiliary cutting holes provides support for effectively expanding cutting cavities; and the cutting method is to arrange nine main cutting holes, the center hole is charged, the remaining eight holes are empty holes, the auxiliary cutting holes are distributed in the upper direction, the lower direction, the left direction and the right direction of the nine holeslocated in the center andfour corners of a peripheral square, a small number of charged holes and a large numberof empty holes are combined forcutting blasting, the blasting efficiency is improved, the unit consumption of the explosives is reduced, and the blasting effect of the cutting holes is improved.

The invention provides a method for improving the fatigue reliability of an axle box positioning node and the axle box positioning node. The axle box positioning node is designed to comprise a mandrel, a rubber layer, a sectioning cover and an integral cover; by means of vulcanized adhesion between the rubber layer and the mandrel, partial vulcanized adhesion between the rubber layer and the sectioning cover and pressing of the positioning node in the integrated cover after partial assembly, the free surface of the rubber layer is increased on the basis that the adhesive strength between the rubber layer and the mandrel and between the rubber layer and the sectioning cover, so that the internal stress of the rubber layer is conveniently and greatly released in time when the axle box positioning node is loaded, the situation that cracks occur due to rubber stress concentration is avoided, and the service life of the product is prolonged.

The invention relates to methods for tunneling, in particular to a sectional type slotting method. The sectional type slotting method includes the following steps that a square slotting region is arranged on the slotting surface of a tunnel, a first set of blast holes are formed in the midpoints of four edges of the square slotting region, a second set of blast holes are formed in four corners ofthe square slotting region, and a compensation hole is formed in the center of the square slotting region; explosives are placed at the bottoms of the first set of blast holes and the second set of blast holes, and orifices of the blast holes are blocked; and the first set of blast holes are detonated at first, and detonation of the second set of blast holes is delayed. Due to the fact that the depths of the slotting holes are different in the tunneling direction in a sectional type slotting mode, free surfaces are created for the second set of blast holes after the first set of blast holes are detonated, the slotting effect is improved, detonation clamping performance of the detonation bottoms is reduced, and the detonation effect of the detonation bottoms is greatly improved.

The invention relates to a controlled blasting construction method of a beam nest on a vertical shaft wall. The method comprises the following steps that the beam nest outline boundary is determined on the vertical shaft wall; a set of corner blasthole is arranged and constructed in each corner of the beam nest according to the beam nest outline boundary, a central blasthole is arranged and constructed in the center of the beam nest, and at least one set of auxiliary blasthole is arranged and constructed between each corner blasthole and the central blasthole; 90-degree kerf explosive tubes are arranged in all the corner blastholes, and a first-section explosive and second-section explosives are arranged in the central blasthole and the auxiliary blastholes; and detonating is carried out according to the detonating sequence of corner blasthole explosives, central blasthole top explosives, auxiliary blasthole top explosives, central blasthole bottom explosives and auxiliary blasthole bottom explosives to finish controlled blasting construction of the beam nest. According to the method, 90-degree kerf explosive bags are arranged in the corner blastholes of peripheral holes of the beam nest to form vibration isolation pre-cracks, and a staged and sectioned blasting manner is adopted in a main blasting area, so that safe and efficient controlled blasting of the beam nest on the vertical shaft wall is realized.

The invention belongs to the technical field of coal seam mining devices, and particularly relates to a thin and extremely thin coal seam mining method and device. An underground mine coal field is divided into a plurality of mining areas, air return roadways, belt conveyance roadways and track conveyance roadways in the mining areas are developed, and ventilation and conveyance systems of the mining areas are constituted; upper roadways and lower roadways and open-off cuts are driven along the coal seam direction, and independent return air systems are constituted; belt conveyors and scraperreversed loaders are installed in the lower roadways, coal conveyor systems are formed through milling coal holes in working faces and belt conveyors in the mining areas, and self-moving air bag supports are installed in the open-off cuts; and coal is ploughed through coal ploughs, and the ploughed coal is transported into the down trough scraper reversed loaders. Equipment operators all work in well-supported roadways without entering the working faces. The self-moving air bag supports are adopted to support roofs, and the coal ploughs move back and forth in the working faces to complete themining process of cutting, loading, transporting, supporting and treatment, thus 0.4-0.8 ultra-thin coal seam working face unmanned mining is realized.