A plate clutch has three discs on the driving shaft and two discs on the driven shaft. -
The inside and the outside diameters of the friction surfaces are 125 mm and 250mm resp. - Assuming uniform pressure and coefficient of friction equal to 0.3, find the total spring load Pressing the plates together to transmit 30 kW at 1500 rpm. -

Mumbai University > MECH > Sem 5 > Theory Of Machines 2

Marks: 7 M

Year: Dec 2014

Given:

R0 = 0.125m; Ri = 0.0625m

P=30 kW

N= 1500 rpm

. μ= 0.3; n1 = 3; n2=2 ;

. n = n1+n2-1 = 3+2-1 = 4

Solution:

Torque $= T = P/w = P \times 60/ 2πN = 30000 \times 60 / 2 π \times 1500 \\ = 190.8 Nm$

T $=n \times μ \times F \times Rm \\ = 4 \times 0.3 \times F \times 2/3 \times (R0^3-Ri^3) / (R0^2-Ri^2) \\ = 4 \times 0.3 \times F \times 2/3 \times (0.125^3-0.0625^3) / (0.125^2-0.0625^2)$

F = 1635.4 N