Research on management method of single hydraulic props row Sun Guangyi Heilongjiang Institute of Mining Resources and Environmental Engineering Department, Heilongjiang Chicken Two 158105 board management method. It concentrates on the advantages of the method of arranging the top control and is the reform of the mining process. After nearly ten years of practice, the goal of reducing costs by means of safe and efficient reduction of the recovery process has been realized.
The method of the medium hydraulic classification 0355.3 single hydraulic prop as the support for the mining face has been widely used, and it has superiority compared with the metal friction strut. However, the theoretical method of controlling the top of the single hydraulic props has not changed. The method of roof management using metal wood pillars directly limits the scope of application of the single hydraulic props.
In the long-term production practice, Jixi Mining Bureau has summarized an effective single-hydraulic pillar management method, namely the drainage management method. Based on the practice, an empirical formula for determining the support parameters of the Jixi Mining Bureau has been established.
1 row management method 1.1 row control top method Since the 1990, the Jixi Mining Bureau has been directly testing the top-end receiving date of the 19991228 method. At present, more than 40 coal mining teams have used this method to manage the roof.
It differs from the row-recovery process in the arrangement of the topping and supporting processes. The maximum number of rows of pillars in the mining face with the top-control top method is the same. The length of the pillars is the same as the row-supporting roof along the entire length of the working face. .
Arrangement of the top plate management method Work surface layout 1. Support density row spacing 0.6, column spacing 0.7 claws see 1.2 discharge top and pillar process arrangement of the top control method is to achieve the maximum control top distance preparation after the working surface is transferred to the conveyor When the column is placed on the top, the pillars are retracted in the order of the top row, and the retracement pillars are immediately re-supported in the corresponding positions of the row, so that the 1st composition always has the row-supporting roof and the top of the row. The return post process of this method is similar to the transfer process of the sliding top beam single combination bracket.
Row row name row row row maximum control top distance minimum control top distance normal production shifting front row control top working surface only row of pillars top row row support branch row pillars, the other are row pillar support roof.
The time when the pillars support the roof is the sum of the time of the back arch branch, about 34.
Controlled top row 1 row management; 2 row management 2.2 row control top placement top roof drop amount Small topping process is the main cause of roof sinking, which is the result of roof plate redistribution. When the old top is broken, the block is more human. After experimental research, there is a certain bite cooperation in the direction of the strike and the tilt direction, so that the pressure balance is reached in a large range. The row is seen at the minimum support density and the supporting capacity of each row of pillars is relatively balanced, so that some old top rocks are transferred to a region with a large support density. The roof drop caused by the topping is not only affected by the supporting ability of the top pillar itself, but also affected by the support capacity of other pillars within the fixed range of the top pillar, that is, the supporting ability of the other pillars in the vertical 4 transverse direction, see 1.
The theoretical basis of the 2 row control top 2.1 The initial support force of the row control top pillar will cause the roof pressure to redistribute during the topping process. The top plate sinking disk is large, and the roof pressure change caused by the topping requires a certain time and process to reach a new equilibrium state.
The pillars of the top retracement are immediately supported in the first row, which already has a fixed initial support force of 46. At the same time, due to the influence of the roof pressure change caused by the topping, the initial support force of the first row of pillars is raised. Through the observation of mine pressure on a working face, under the same coal seam and mining conditions, the initial support force of the top of the row control top is higher than that of the top support pillar. Because of the large initial force of the pillar, it can effectively control the direct top layer and make each The supporting capacity of the row of pillars is relatively balanced, which is convenient for roof management. The supporting force of the left and right working face of the mining area of ​​the East China Sea Mining Area of ​​Jixi Mining Bureau 2 and the pillar load, the exhibition number, the method of controlling the top of the halogen number, the theoretical analysis and statistics, the subsidence of the roof caused by the topping obeys or approximates half Dimensional normal distribution, see 3 no.
Dimensional normal distribution density function See Formula A longitudinal 4 direction pillar support capacity variance; G1 transverse direction direction pillar support capacity variance; r autocorrelation coefficient.
When the width is small, the support capacity of each row of pillars is relatively balanced, the variance is small, and the amount of roof subsidence caused by the topping is small. When the supporting power of the top pillar is large, and the support capacity of other pillars in the nearby range is small, the variance is large and the roof sinking amount is large.
According to statistical analysis, the support capacity of the row of pillars is more balanced than that of the rows of pillars, and the variance is small. From 2, the statistical result is the row pillar = 0.466; row = 537. The roof subsidence caused by the topping is reduced by 810.
2.3 The top of the row control top reaches the top of the control top. The main purpose of the control is to prevent the goaf from falling into the working face and push down the pillar, and at the same time, it is convenient for workers to operate safely.
The top of the row control is to use the number of pillars of the top surface of the drainage control to achieve the purpose of row support. It concentrates on the process of sorting and controlling the top return, and the labor intensity of workers is low.
3 row control top adaptation conditions 3.1 meters high displacement control top is to return to the top of the column when the maximum control top distance support density of the working surface is the smallest. Although the support time of the pillars is shorter than 34, it is still the most dangerous area of ​​the working face. Therefore, considering the most dangerous conditions such as the top plate type crack and the safety factor, the displacement control top is adapted to the coal seam with a height of less than 1.8 m.
3.2 Coal seam dip angle In order to prevent the returning column from topping, the gob area of ​​the gob area is affected by the falling of the pillar and affecting the normal production. The row top is adapted to the coal seam inclination angle less than 25.
3.3 Top plate type According to the characteristics of the top control and the support state of the most dangerous area, the top top thickness of the working face is required to be 13 times the height of the working face, and the upper part is the old top.
4 Conclusions 4.1 The top-of-pipe method focuses on the advantages of row-discharging and controlling the support process of the pillars. It is a major reform of the single-hydraulic pillar roof management and achieves safe and efficient mining purposes.
4.2 The top of the row control method The pillars have large initial support force, and the roof sinking caused by the topping is small, which is convenient for roof management.
4.3 The top-loading mining face has low investment, low yield, low working cost, simple and reliable process, and low labor intensity. Through the practice of using this method, the working face can increase the yield by 8, reduce the investment by 130,000 yuan, save the annual cost, and save more than 10,000 yuan.
Sun Guangyi. Single hydraulic props top plate pressure calculation. Journal of Heilongjiang Mining Institute, 1998, 8169. Graduated from the Mining Department of Fuxin Mining College in 1980, mainly engaged in mining system engineering, research in the field of mining methods, successively in the Journal of Coal. Papers on coal science and technology and other publications 2, the rest.
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