The applicable geology of spiral drill bits varies depending on the type and structure of the drill bit. The soil auger bit is suitable for soil layers above the water table, sand layers, dense sand layers containing a small amount of clay, and sand and gravel layers with small particle sizes. Rock auger bits are suitable for weathered bedrock, well-cemented pebble gravel formations and permafrost soil layers .
The tapered double-headed double-screw drill bit is suitable for hard bedrock. The double-headed single-screw drill bit is suitable for weathered bedrock, pebbles, frozen soil, etc. Among the straight spiral drill bits, the bucket tooth type is suitable for sandy soil and small-diameter gravel layers with poor cementation; the double-head single-spiral type is suitable for sandy soil and soil layers; the single-head single-spiral type is suitable for large-diameter pebbles, clay soil and hard cement with poor cementation. Straight pick bits are suitable for hard bedrock or pebbles
