Question

The band brake shown in the figure is to have a maximum lining pressure of 600 kPa. The drum is 350 mm in diameter, and the band width is 100 mm. The coefficient of friction is 0.25 and the angle of wrap is 270 band tensions of the brake are

Answer 1

$W=100mm$

$D=350mm,$

$P_{max}=600kPa,\theta ={270}^{\circ },\mu =0.25$

$\frac{T_1}{T_2}=e^{\mu \theta }$

$\frac{T_1}{T_2}=e^{(0.25\times \frac{3\pi }{2})}$

$\frac{T_1}{T_2}=3.25....\left(i\right)$

$\text{Maximum lining pressure}$

$=\frac{2T_{max}}{D\times W}=\frac{2T_1}{D.W}=600kPa$

$T_1=0.350\times 0.1\times 600=10.5kN$

$\text{Hence, from equation (i)}$

$T_1=10.5kN,$

$T_2=3.2kN$