Blind drilling refers to drilling a shaft from the surface. No underground access is required, and personnel are not required to enter the shaft during the drilling process. Blind drilling can be utilized when raise drilling or conventional shaft sinking is not feasible due to challenging overburden ground conditions. A blind-drilled shaft can be constructed prior to the underground advancement and off the critical path. Frontier-Kemper has completed more than 5,000 ft. of blind-drilled shafts across the US and has the capacity to drill diameters ranging from 6 ft.–20 ft. and depths of more than 2,000 ft. with special applications.
To provide solutions for mechanically excavated, deep, large-diameter, blind-drilled shafts, Frontier-Kemper, Wirth GmbH, and ACI entered a joint cooperation agreement to build a blind shaft drilling system. The result is the FK350MT; one of the largest, safest, and most efficient A-Frame type drilling rigs in North America. As currently configured, the FK350MT is capable of drilling shaft diameters up to 20 ft. and depths of more than 1,500 ft.