1.Institute of Exploration Techniques, CAGS, LangfangHebei065000, China;2.Langfang Juli Exploration Technology Co., Ltd., LangfangHebei065000, China;3.Technology Innovation Center for Large Diameter Rock & Soil Drilling, Hebei Province,Langfang Hebei 065000, China;4.Innovation Base for Automatic and Intelligent Drilling Equipment, Geological Society of China,LangfangHebei065000, China
P634.4;TE921