Deep Cobalt Crusts Core Drill Drilling A Pilot Study Of The Process Parameters

Before exploring the abundant ocean mineral resources, the research and development of high quality exploring equipments are very important. So it is not only manful but also strategic to develop a submarine based cobalt sampler, which can provide us cobalt sample that has plenty of geologic information. This information is crucial for exploring ocean minerals, demarcating diggings and the research of mining equipments.In the first place, the paper analyzed the research background, status of the seabed sampling technology and the diamond bit coring technology.Secondly, combining the analysis of physical properties and mechanical cutting characteristics of cobalt-rich crust and the impregnated diamond bit coring mechanism, the paper analyzed its minimum pressure when cutting cobalt and base rock.Base on the analysis of the second step, the coring process of impregnated diamond bit was analyzed in detail, and optimized coring parameters were reached.In the fourth part, the effect of deep-sea environment——highpressure and low temperature on the viscosity of hydraulic oil was analyzed and the pressure loss in lab and deep-sea were calculated accurately.At last, minimum pressure test and drilling parameters test were carried out on the prototype of cobalt sampler. The test results were discussed and an optimizing coring parameters group was found. The testing results match well with the forgoing theory analyses.All of contents in the dissertation represent strong innovation and realistic significance. The paper laid a solid base for cobalt sampler's sea tests in future.