Definition - What does Drill Bit mean?
A drill bit is the cutting device located at the end of a drilling machine's drill string. Like the bit on a hand-held drill, it creates a passage through the material into which it bores. It may assist -- to some extent -- in removing the material which it cuts away to form the passage. The drill bit is an essential piece of equipment in a trenchless drilling project.
Trenchlesspedia explains Drill Bit
Drill bits come in several forms and sizes, and may be called by other names including, simply, "The bit." It's also known as the BHA, the bottom hole assembly.
Drill bits are selected based on the equipment to be used, the nature of the job to be done and the challenges expected on the job. For example, a trenchless microtunnelling operation designed to house a water line running from a residential water meter to a home wouldn't require a 28-inch surgical drill bit, and a 48-inch tunnel beneath a riverbed would take forever using a 4-inch horizontal reamer bit.
Finally, drill bit designs vary and include roller cone rock bits, horizontal reamer bits and a wide range of surgical drill bits with diamond cutting heads that bore gas and oil wells into the Earth's surface.