(1) The mining depth is less than 300m, which is called shallow mining. Within this depth exploration of metal deposits, generally pressure behavior is not serious. Even if the ground pressure activity occurs, it is a static pressure problem and easy to handle. (2) The mining depth is between 300 and 600 m, which is called medium depth mining. In this depth of mining, depending on the conditions of the ore body, the physical and mechanical properties of the ore, during the process of tunneling or opening the roadway, mild rockburst, such as rock ejection, may occur. In the Soviet metal mines, 59 mines began to have deep ground pressure activities since the 1970s. By September 1984, they were recorded in the North Ural Bauxite Mine, the Tashtagor Mine and the Krivorog Mining Mine. 55 and 14 rock bursts. The first rockburst in the Tashtagor mine occurred at a depth of 300m. The depth of rockburst in the Witwatersrand gold mine in South Africa is 600m. China's Pangushan tungsten mine, Yangjiazhangzi molybdenum mine, also appeared in varying degrees of rock ejection. Zhangjiawa Xiaoguanzhuang iron ore in sinking ground crusher chamber (above the surface of 500m), ejection from the rock cavern roof down phenomenon occurred. (3) The mining depth is 600-2000m, which is deep mining. During this deep mining, frequent rockbursts occur in rocks with two types of deformation characteristics. Moreover, some mining methods will encounter insurmountable difficulties when the depth exceeds 700m, and it is difficult or even impossible to perform normal mining work in the stope. Such as Jilin Shiju child copper mine application Shrinkage Method, when mining depths greater than 300m, ore rooms ranging pillar stope mining is completed, that was strongly pressed role crushed conduct security is threatened, the upper and lower plate surrounding rock convergence The ore in the stope is difficult to release. (4) The mining depth is more than 2000m for ultra-deep mining, and there are not many mines currently in ultra-deep mining. compression fittings 's ring has double anneal,It is much better for seal.compression fittings,Connex compression fittings,Plumbing compression fittings compression fittings,Connex compression fittings,Plumbing compression fittings Taizhou Runde Company , https://www.smartfittings.com
Mining depth classification