Question

A hole shaft pair is specified by $25H_8{d}_9$, the basic size lies between 18 and 30 mm, IT9 = 40i, IT8 = 25i and fundamental deviation for shaft 'd' is $-16D^{0.44}$. The NO-GO ring gage size is

• A. 25.000
• B. 24.936
• C. 24.884
• D. 25.033

Answer 1

The correct option is C 24.884

$25H_8{d}_9$

$D_1=18$

$D_2=30$

No-Go ring gage = L.L of shaft
$D=\sqrt{18\times 30}=23.23$

$I=0.45D^{\frac{1}{3}}+0.001D\text{in}\mu m$

$\text{Tolerance of shaft}=IT9=40I=52.295\mu m$

= 0.0522 mm

$\text{Fundamental deviation of shaft}=-16D^{0.44}$

$=\frac{-63.86}{1000}=0.0638mm$

L.L of shaft = 25 - 0.0638 - 0.0522 = 24.88