The ratchet housing 92 extends inwardly from {HEAD ~ the inside surface} of the drill string 32 and {TAIL ~ washover pipe} 40 
of
The ratchet housing 92 extends inwardly from { HEAD ~ the inside surface } of the drill string 32 and { TAIL ~ washover pipe } 40
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH