33results about How to "Improve drilling utilization" patented technology

The invention relates to a detection system and a method for monitoring fracture development of a coal pillar-free gob-side entry retaining floor. The method comprises the following steps of chiseling a floor drilling field at one side of the coal pillar-free gob-side entry retaining, drilling in a floor rock layer according to different angles, gradually butting transparent hollow pipe sections by a butting sealing system, and sending into each drilling hole; grouting and anchoring a gap between each drilling hole and the corresponding transparent hollow pipe, enabling a detection positioning assembly to record the fracture of the drilling surrounding rock according to different scales of a measuring tape, performing monitoring tasks on evolution of floor mining failure rule for multiple times in different mining phases until the data is stable, and then finishing the observation. The method has the advantages that the floor small-angle drilling hole, the floor medium-angle drilling hole, and the floor large-angle drilling hole extend from the drilling field to the floor of a to-be-mined coal layer and are distributed in parallel in a stereo way; by observing the fracture condition of adjacent drilling holes in the same time and the fracture condition of the same drilling hole in different coal mining phases, the development state of the plastic failure area of the floor and the development state of the failure area of the floor after the coal bed is mined are determined, so as to provide reliable data reference for safety construction.

The invention discloses a combined multi-electrode high-voltage pulse discharge fragmentation hard rock device and a fragmentation method, which are applied to the rock mass to be crushed, including: a negative electrode, a positive electrode and a pulse power meter; the rock mass to be crushed is pre-set There are a plurality of operation holes adapted to the negative electrode and the positive electrode, and the negative electrode and the positive electrode are electrically connected to the pulse power meter; the present invention uses one negative electrode or a small number of negative electrodes Cooperate with the electrode arrangement of multiple positive electrodes to effectively avoid edge discharge.

The invention discloses a space and time coordination control weakening method for a hard coal seam roof. The space and time coordination control weakening method comprises the steps that firstly, a plurality of advanced weakening fracturing drilling groups are drilled in sequence in the advance direction of the coal seam working face on the roof of a return air roadway, wherein each advanced weakening fracturing drilling group internally comprises a first row of fracturing drill holes, a second row of fracturing drill holes and a third row of fracturing drill holes which are arranged in sequence in the advance direction of the coal seam working face, and all the three rows of fracturing drill holes are inclined at different angles towards the direction of a goaf; and when the coal seam working face advances to the position of the advanced weakening fracturing drilling groups, the three rows of fracturing drill holes are filled with static crushing agent cartridges in sequence to realize gradual fracturing weakening of the roof rock layer. According to the method, the best effect of the cartridges is achieved by using the free surface to create a free face or a weakening layer, ''gradual weakening + overall fracture '' is achieved, and the space and time coordination fracturing of the drill holes with different tilt angles of the roof is realized, so that the roof caving efficiency is enhanced. The space and time coordination control weakening method for the hard coal seam roof is simple in structure, and the fracturing effect is good.

Provided is a coupling fracturing method for a hard coal bed roof. A drilling machine is utilized for drilling fracturing drill holes inside the hard roof till the design position, specifically, each static fracturing guide drill hole is formed between every two pulse hydraulic fracture drill holes so as to form a fracturing system; the fracture drill holes are connected to a pulse water injection pump through an isometric flow distributor with adjustable frequency, and the static fracturing drill holes are filled with static crushing agent slurry; under the action of expansion force of the static crushing agent slurry, initial cracks formed around the drill holes are monitored, released heat irradiates continuously towards the portions around the drill holes, a similarly elliptical temperature field is generated, and the elasticity modulus of a rock stratum is reduced; and under the action of hydraulic pressures of different frequencies, a fracture zone, a fatigue zone and an original stress zone are formed in the positions, around the fracture drill holes, of the rock stratum, when pressure water flows to the rock stratum bearing heat conduction along the cracks, the water and heat effect weakens the strength of the rock stratum, and the through time for crack zones among the drill holes is shortened. The method can sufficiently improve the utilization rate of the drill holes, operation is easy, and construction is safe and reliable.

The invention discloses a four-period-five-purpose hole-drilling high-efficiency gas extracting process, comprising the steps of: drilling a measure hole from a rock stratum tunnel wall of a coal seam top plate rock stratum tunnel to one side of the rock stratum tunnel and drilling a extracting hole from the rock stratum tunnel wall of the coal seam base plate rock stratum tunnel to a coal seam working face; performing shock blasting and / or hydrofracture to the measure hole for increasing the permeability of the coal seam, wherein the measure hole is a rock hole in the top plate or base plate rock stratum of the coal seam and positioned over or under the coal seam working face; sealing the measure hole and the extracting hole for extracting gas, and then tunneling the tunnel of the coal seam; continuously extracting the gas in the coal seam through the measure hole and / or the extracting hole when before and in stope. According to the four-period-five-purpose hole-drilling high-efficiency gas extracting process, the high-efficiency gas extraction in periods of tunneling the coal seam tunnel, and before, in and after stoping on the working face can be achieved. And simultaneously, the four-period-five-purpose hole-drilling high-efficiency gas extracting process can shield the tunneling of double coal seam tunnel of the working face.

The invention relates to a method for constructing a directional hole in an upward penetration layer on an underground mining gas drainage roof of a coal mine. The present invention utilizes the drilling field that has been excavated into the air roadway at the adjacent working face of the working face to be mined, and utilizes equipment such as pilot directional drilling tools and impact compound reaming drilling tools, and adopts multi-stage rotary reaming technology, sliding directional drilling technology, and composite drilling technology. Directional drilling technology and percussion compound reaming technology drilled to obtain directional holes on the roof through the layer, so that they can enter the roof mining fracture zone and abscission zone in advance, and extend for a long distance and large diameter. After the drilling construction, when the working face to be mined is recovered, the upward fissures formed by the mining on the roof layer are connected with the directional holes in the upward penetration layer on the roof. The use of dynamic gas drainage solves the shortcomings of the current mining gas drainage drilling, such as small hole diameter, short extension distance of the fissure zone, low drilling efficiency, high cost, and long construction period, and improves the effect of mining gas drainage.