The other major factor causing the punch to draw the sheet metal and not cut it is the amount of clearance.
Earing sheet metal drawing.
Earing is one of the major defects observed during deep drawing process due to anisotropic nature of sheet metal.
Earing is one of the major defects observed during deep drawing process due to anisotropic nature of sheet metal.
Knowledge about ear formation in deep drawing process allows a prior modification of process which can result in defect free final product with financial saving and time.
Earing is defined as formation of waviness on uppermost portion of deep drawn cup.
Clearance in cutting operations is relatively small usually 3 to 8 of sheet metal thickness.
In deep drawing manufacture if the clearance is too small the sheet may be cut or pierced not well despite the radius.