Study On The Change Law Of The Influence Range Of The Drilling Hole In The Coal Bed Of Machi Coal Mine

The technology parameter is not clear when the ? 1 coal seam of the Machi coal mine adopts the drilling technology.Especially the effective influence radius of hydraulic punch.This article aimed at this situation,using theoretical analysis,numerical simulation,field test and other methods to study the parameters of hydraulic punching technology,especially the effective influence radius of hydraulic punch.this paper mainly studies the following aspects of content:First,By using COMSOL Multiphysics numerical simulation software,Simulated under the condition of certain rushed out of the coal hydraulic punching the scope of the law of gradual change over time.The results showed that the hydraulic punching effective influence radius with the gas pumping production time simulated by a gradient of rules is R=2.1075ln(t)-3.5843.Secondly,guided by numerical simulation,field test test hydraulic punching hole around the residual gas content of coal extraction from different time.The results showed that the hydraulic punching effective influence radius with the gas pumping production time by a gradient of rules is R=2.1542ln(t)-3.9043?Again,In order to enhance the pressure relief and permeability increasing effect of hydraulic punching,the test has been applied to the blasting of air blasting.The results show that the effective improvement of the effective influence radius of the hydraulic punching hole R with the t of the gas drainage time is improved by the air blasting and blasting.After the inspection,air blasting promoting pumping measures can promote the drilling of coal body around the creep,the punching hole of coal body around the steady state was destroyed after to reach a stable state to the desired time is shortened 5d~8d;regression analysis after the implementation of the air blasting auxiliary measures hydraulic punching has effects of radius r with the gas pumping recovery time t change rule for R=1.5967ln(t)-1.4366.Finally,According to the hydraulic flushing influence scope change rule identified for Ma Chi coal seam hydraulic punching hole cloth hole technology parameters,hydraulic punching and other technology parameters are obtained by means of numerical calculation method,and follow-up inspection of the hydraulic punching increased penetration pumping effect and working face outburst situation.The results show that the average increase of the permeability of the coal seam is 131 times;the gas content of the coal is reduced to 3.09~5.75m3/t,and the outburst danger of the coal is eliminated;the driving speed of the roadway is increased by 112.5%.Through the above content,this paper finally gets the machi coal mine hydraulic punching effect change rule,hydraulic flushing technology parameters for Machi coal mine were determined.