A drag bit is a drill bit usually designed for use in soft formations such as sand, clay, or some soft rock. However, they will not work well in coarse gravel or hard rock formations. Uses include drilling water wells, mining, geothermal, environmental and exploration drilling.
Types of Drag Bits
Step Type Drag Bits:
They are primarily designed for soft to medium formations.
Three-Wing and Four-Wing:
Three-wing bits tend to drill faster whereas four-wing bits are longer lasting, more durable, and drill a straighter hole.
Chevron Type Drag Bits:
Chevron-Type drag bits are recommended for drilling in slightly harder and more consolidated materials than step-type drag bits such as hard shales, limestones, and tougher gravels.