Abstract: A multi-sectional percussive drill bit assembly for drilling holes in earth formation primarily used in conjunction with a pneumatic percussive device. The drill bit assembly is comprised of an easily removable bit that is rotationally driven by a lug and pocket structure and axially limited in travel by means of retaining members.

Abstract: A multi-sectional percussive drill bit assembly for drilling holes in earth formation primarily used in conjunction with a pneumatic percussive device. The drill bit assembly is comprised of an easily removable bit that is rotationally driven by a lug and pocket structure and axially limited in travel by means of retaining members.

Abstract: This invention provides a method of creating air pressure by generating a source of air pressure greater than atmosphere air pressure from a first rotary screw compressor. The first rotary screw compressor has a first displacement and is driven by a first power source. The generated source of air pressure from the first rotary screw compressor is directed to a second rotary screw compressor having a second displacement which is less than the first displacement and which is driven by a second power source which is independent of the first power source. The generated air pressure from the second rotary screw compressor driven by the second power source is greater than 200 psi.