为提高地下工程反井（天井）掘进的效率和安全，研制了ＬＭ系列反井钻机，该机在煤炭、冶金、水电等系统得到广泛应用，社会、经济效益显著。 In order to improve the efficiency and safety of anti-shaft (patio) excavation in underground engineering, LM series drilling rig has been developed. It has been widely used in coal, metallurgy, hydropower and other systems and has significant social and economic benefits.