Based on the analysis of difficulties encountered in drilling large diameter base rock hole and comparison of various coring methods.The author put forward solution and designed the rudimental configuration of new typ...Based on the analysis of difficulties encountered in drilling large diameter base rock hole and comparison of various coring methods.The author put forward solution and designed the rudimental configuration of new type bit.展开更多
文摘Based on the analysis of difficulties encountered in drilling large diameter base rock hole and comparison of various coring methods.The author put forward solution and designed the rudimental configuration of new type bit.
