Question

A metal disk of 30 mm diameter is to be punched from a sheet of 5 mm thickness. If the punch and die clearance is 4%, then the required diameter of punch is

• A. 29.60 mm
• B. 30.40 mm
• C. 30.20 mm
• D. 29.80 mm

Answer 1

The correct option is A 29.60 mm

Given: Sheet thickness = 5 mm
So, clearance = 4 % of 5 mm
c = 0.2 mm

Hence, punch diameter,

$D=d-2c=30-0.2\times 2=29.60mm$