Question

In a two-pass wire drawing process, there is a 40% reduction in wire cross-sectional area in 1st pass and further 30% reduction in 2nd pass. The overall reduction (in percentage) is ______

Answer 1

Explanation:

Let the initial diameter be d_o.

Diameter after the first pass d₁ = 0.6 d_o

Diameter after the second pass d₂ = 0.7 d₁ = 0.7 × 0.6 d_o

Thus, the ratio of final to initial diameter is:

\(\frac{{{d_2}}}{{{d_o}}} = 0.7 \times 0.6 = 0.42\)

The overall reduction will be 1 – 0.42 = 0.58 = 58%