It is required to punch a hole of diameter $$10mm$$ on a sheet of thickness $$3mm.$$ The shear strength of the work material is $$420MPa.$$ The required punch force is

A cup is to be drawn to a diameter of $$70mm$$ with $$35mm$$ depth from a $$0.5mm$$ thick sheet metal. The cup is drawn in one operation. Assume $${\sigma _u} = 430\,\,MPa.$$

The required blank diameter is

A cup is to be drawn to a diameter of $$70mm$$ with $$35mm$$ depth from a $$0.5mm$$ thick sheet metal. The cup is drawn in one operation. Assume $${\sigma _u} = 430\,\,MPa.$$

The maximum drawing force is

A $$\phi \,\,25$$ $$mm$$ hole is pierced in a $$t=2.5mm$$ thick steel sheet having shear strength $$\tau = 350\,\,MPa.$$ If the diametral clearance is given by the expression $$C=0.0064$$ $$t$$ $$\sqrt \tau ,$$ the die diameter (in $$mm$$), punch diameter (in $$mm$$) and punch force in $$(kN)$$ respectively are