Advanced Sealed Bearing Asembly for Positive Discplacment Motors used in Micro-borehole Driling

78930S Advances in "microhole" technologies, which use portable drilling rigs with a smaller footprint and lower environmental impact, are needed to benefit the small driller. This project will develop an advanced sealed bearing assembly for positive displacement motors (PDMs) suitable for micro-hole drilling. Advanced hydrodynamic rotary seal and thrust bearing designs, as well as the seal bearing assembly, will be developed, while properly accounting for the technical issues related to the scaling-down of components. In Phase I, alternative concepts for advanced hydrodynamic seal and bearing designs will be evaluated by extensive finite element analyses. Final designs will be fabricated and tested in the laboratory using a combination of pressures, speeds, and temperatures that simulate microhole drilling conditions. The overall design will be evaluated by structural and fatigue analyses to provide a life in excess of 1000 hours. Commercial Applications and other Benefits as described by the awardee: The advanced sealed bearing assembly will be designed to mate with any of the PDMs currently being developed to meet the DOE's microhole drilling goals.