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 $$\phi \,\,25$$ $$mm$$ 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

A cylindrical cup of $$48.5$$ $$mm$$ diameter and $$52$$ $$mm$$ height has a corner radius of $$1.5$$ $$mm$$ Cold rolled steel sheet of thickness $$1.5$$ $$mm$$ is used to produce the cup. Assume trim allowance as $$2$$ $$mm$$ per $$25$$ $$mm$$ of cup diameter. What is the blank size in $$mm$$ ?

A hole of $$40$$ $$mm$$ diameter is pierced in a steel sheet of $$4$$ $$mm$$ thickness without shear on the tool. Shear strength of steel is $$400$$ $$N/m{m^2},$$ and penetration is $$25\% .$$ What is the expected percentage load reduction if a shear of $$1$$ $$mm$$ is provided on the punch?