A metal strip is to be rolled from an initial wrought thickness of $$3.5$$ $$mm$$ to a final rolled thickness of $$2.5$$ $$mm$$ in a single pass rolling mill having rolls of $$250$$ $$mm$$ diameter. The strip is $$450$$ $$mm$$ wide. The average coefficient of friction in the roll gap is $$0.08$$. Taking plane strain low stress of $$140$$ $$MPa,$$ for the metal and assuming negligible spreading, the roll separating force is . . . . . . . . .

A strip of thickness $$T$$ $$mm$$ is rolled in a $$2$$ high single pass rolling mill, having roll diameter $$D$$ $$mm,$$ to a final thickness of $$\left( {T - 2\Delta T} \right)mm.$$ If the friction coefficient between the roll and strip is $$\mu ,$$ calculate the maximum reduction $$2\Delta T$$ possible in this operation. Using this relation, for $$D=300mm,$$ $$T=40mm$$ and friction coefficient is $$0.3,$$ calculate the outgoing thickness of the strip. If the inlet velocity is $$5m/s,$$ what is the outgoing strip velocity?.