1 results listed
Cold forging of flange welding nuts requires proper
design of forging stages to get tight dimensional tolerances of
welding bulges and high tool life. In this study, reasons of low tool
life of cold forged M10x1.25 welding flange nuts were determined
by using finite element simulations and then forging stage designs
were modified to decrease the tool stresses. Finite element
simulations of cold forging operations were prepared in
commercial finite element code Simufact.forming. Forging tests
showed that two forging tools at forging stage 5 fractured due to
fatigue failure during forging of 2,500 welding nuts. Numerical
simulations revealed that preform of the nut before fifth forging
stage was not properly formed and this led excessive increase in
forging force during flow of the material in stationary tool in
following forging stage. In fourth forging design, flat punch
geometry was replaced by stepped punch design and closed
forming case was formed on the stationary tool. It was seen that
forging force in the fifth forging stage was decreased to 64 tones
from 92 tones. Forging tests conducted with this design showed
that tool life in fifth forging stage was increased more than 200%
International Iron & Steel Symposium
UDCS
Sezgin Yurtdaş
Cenk Kılıçaslan
N. Emrah Kılınçdemir
Barış TANRIKULU
Buğra Karahan