Then a bulge is formed on the head portion of the cut coupling element by a bulge forming die, which is connected with the forward end in {HEAD ~ stroke direction} of {TAIL ~ the cutting die}, and a coacting bulge forming punch, which is movable upwardly and downwardly 
of
Then a bulge is formed on the head portion of the cut coupling element by a bulge forming die , which is connected with the forward end in { HEAD ~ stroke direction } of { TAIL ~ the cutting die } , and a coacting bulge forming punch , which is movable upwardly and downwardly
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 REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH