Question

GO and NO-GO plug gauges are to be designed for a hole ${20.000}^{\begin{array}{c}+0.050\\ +0.010\end{array}}mm.$

Gauge tolerances can be taken as 10% of the hole tolerance. Following the ISO system of gauge design, sizes of GO and NO-GO gauge will be respectively.

• A. $\text{20.014 mm and 20.046 mm}$
  
• B. $\text{20.006 mm and 20.054 mm}$
• C. $\text{20.014 mm and 20.054 mm}$
• D. $\text{20.010 mm and 20.050 mm}$

Answer 1

The correct option is D $\text{20.010 mm and 20.050 mm}$

$\text{For general purpose ISO system of gauge:}$


$\text{BS of GO gauge = 20.01 mm}$

$\text{LL of GO gauge = 20.01 mm}$

$\text{UL of GO gauge = 20.014 mm}$

$\text{GO gauge will be}={20.01}_{+0.000}^{+0.004}mm$

$\text{BS of NO GO gauge = 20.05 mm}$

$\text{LL of NO GO gauge = 20.05 mm}$

$\text{UL of GO gauge = 20.054 mm}$

$\text{NO GO gauge will be}={20.05}_{+0.000}^{+0.004}mm$

In the question only UL of GO and NOGO is given,

but it's impossible to produce. So the answer will be none of this.