Question

The crankpin of an engine sustains a maximum load of 35 kN due to steam pressure. If the allowable

bearing pressure is 7 N/mm2

, find the dimensions of the pin. Assume the length of the pin equal to 1.2

times the diameter of the pin.

Answer 1

diameter of the pin. d

$\sigma = \frac{W}{A} = \frac{W}{\frac{\pi}{4}d^2}$

$d^2 = \frac{35000}{\frac{\pi}{4}\times 7 }$

$d = 79.78 mm \iff80 mm$

diameter of the pin. d = 80 mm

Length of Pin, $L=1.2d =1.2\times 80 =96mm$