Publications

Advanced percussive drilling technology for geothermal exploration and development DE-FOA-EE0005502

Su, Jiann-Cherng S.; Raymond, David W.; Prasad, Somuri V.; Wolfer, Dale

Percussive hammers are a promising advance in drilling technology for geothermal since they rely upon rock reduction mechanisms that are well-suited for use in the hard, brittle rock characteristic of geothermal formations. Also known as down-the-hole (DTH) hammers, they are also compatible with low-density fluids that are often used for geothermal drilling. Experience in mining and oil and gas drilling has demonstrated their utility for penetrating hard rock. One limitation to more wide-scale deployment is the ability of the tools to operate at high temperatures (∼300°C) due to elastomers used in the construction and the lubrication required for operation. As part of a United States Department of Energy Funding Opportunity Announcement award, Atlas Copco was tasked with developing a high-temperature DTH capable of being used in geothermal environments. A full-scale development effort including design, build, and testing was pursued for the project. This report summarizes the results of the percussive hammer development efforts between Atlas-Copco Secoroc and Sandia National Labs as part of DE-FOA-EE0005502. Certain design details have been omitted due to the proprietary nature of the information.