A rolling mill is used to reduce the thickness of a plate from 50 mm to 25 mm. The roll diameter is 700 mm and the coefficient of friction at the roll work interface is 0.1. It is required that the draft in each pass must be the same. Assuming no front and back tensions, the minimum number of passes required in the rolling are:

A rolling mill is used to reduce the thickness of a plate from 50 mm t

1.	A rolling mill is used to reduce the thickness of a plate from 50 mm to 25 mm. The roll diameter is 700 mm and the coefficient of friction at the roll work interface is 0.1. It is required that the draft in each pass must be the same. Assuming no front and back tensions, the minimum number of passes required in the rolling are:
A.	16
B.	8
C.	4
D.	12
Answer» C. 4