1
GATE PI 1990
MCQ (Single Correct Answer)
+5
-1.5
A steel wire of length $$100$$ $$m$$ and diameter $$12.214$$ $$mm$$ is drawn to a final diameter of $$10mm.$$ Tensile tests of specimen made before and after the drawing operation gave yield stress as $$200$$ $$MPa$$ and $$400$$ $$MPa$$ respectively,

The length of drawn wire is

A
$$100$$ $$m$$
B
$$125$$ $$m$$
C
$$150$$ $$m$$
D
$$175$$ $$m$$
2
GATE PI 1989
Subjective
+5
-0
In a wire drawing operation diameter of $$6mm$$ is reduced in stages to a diameter of $$1.34mm.$$ Assuming ideally rigid plastic material and ideally lubricant condition,
$$i)$$$$\,\,\,\,\,\,\,$$ The minimum number of passes required by assuming max reduction per pass
$$\,\,\,\,\,\,\,\,\,\,\,\,$$ is obtained with $$\mu = 0.2$$ and half die angle as $${6^0}$$. If the flow strength of the
$$\,\,\,\,\,\,\,\,\,\,\,\,$$ material is $$60$$ $$MPa.$$

$$ii)$$$$\,\,\,\,\,$$ The diameter of wire after $${2^{nd}}$$ stage

EXAM MAP