A numerical control unit controls feed units for {TAIL ~ the first and second wheel heads} in order to move the first and second wheel heads independently of each other in the axial direction of the workpiece and in the direction perpendicular to the axial direction, such that each of {HEAD ~ the axially arranged portions} is ground by the grinding wheel, and simultaneously with this, another ground portion is superfinished by the superfinishing wheel 
A numerical control unit controls feed units for { TAIL ~ the first and second wheel heads } in order to move the first and second wheel heads independently of each other in the axial direction of the workpiece and in the direction perpendicular to the axial direction , such that each of { HEAD ~ the axially arranged portions } is ground by the grinding wheel , and simultaneously with this , another ground portion is superfinished by the superfinishing wheel
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH