Large Diameter Drill Bit

At Crownpoint, New Mexico, this drill bit was used to drill a 10-foot-diameter shaft 2,234 feet deep. The drill cutters weighed 30,000 pounds, and the total assembly weighed 443,000 pounds. One third of its weight was used for cutting, while the rest acted as a pendulum to keep the drill stem straight so the shaft would be drilled straight. A large drill rig with a load capacity of 100,000 pounds, a 112-foot mast, and two 615-horsepower diesel engines powered the drill.

Grants, New Mexico · United States