Subtopic: Calculation of power, torque, fuel consumption, heat load and power losses
Question Statement:
A single dry plate clutch has two active friction surfaces with outer radius $140\text{ mm}$ and inner radius $90\text{ mm}$. The total axial clamping force is $2500\text{ N}$ and the coefficient of friction is $0.35$. Assuming uniform wear theory, calculate the maximum torque that can be transmitted in $\text{N}\cdot\text{m}$ (round off to 1 decimal place).
Answer Key:
201.3
Step-by-Step Solution & Explanation
For uniform wear theory, the effective friction radius is:
$R_m = \frac{R_o + R_i}{2} = \frac{140 + 90}{2} = 115\text{ mm} = 0.115\text{ m}$
With $n = 2$ friction surfaces, axial force $W = 2500\text{ N}$, and $\mu = 0.35$:
$T = n \mu W R_m = 2 \times 0.35 \times 2500 \times 0.115 = 201.25\text{ N}\cdot\text{m} \approx 201.3\text{ N}\cdot\text{m}$
Acceptable range: $199.0 - 203.5\text{ N}\cdot\text{m}$.