By further forwarding the elongate body, {HEAD ~ the burnisher} is advanced to engage {TAIL ~ the hole}, so as to create a residual stress beneficial thereto 
By further forwarding the elongate body , { HEAD ~ the burnisher } is advanced to engage { TAIL ~ the hole } , so as to create a residual stress beneficial thereto
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH