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APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
SECOND SEMESTER M.TECH DEGREE EXAMINATION, MAY 201 7

Mechanical Engineering
(Machine Design)

01ME6112: Design of Power Transmission Elements
Max. Marks: 60 Duration: 3 Hours

Instructions: Answer any two questions from each part

Use of data book is permitted

Part A
1) a) How are wire ropes classified? (2 Marks)
b) Design a V belt drive for the following specifications.
Power to be transmitted — 7.5 kW
Speed of driving wheel = 1440 rpm
Speed of driven wheel —400 rpm
Diameter of driving wheel =300mm
Centre distance = 1000 mm
Service = 16 hours / day (7
Marks)
2) a) Explain various stresses that are acting on a belt drive? (2 Marks)

0) Design a wire rope for an elevator in a building 60 m height and for a total toad of 20 KN. The
speed of elevator is 4 m/s and full speed is reached in 10 seconds. (7 Marks)

3) A clutch has 3 discs on the driving shaft and 2 discs on the driven shaft. The outer diameter of
the contact surface is 24()mm and inner diameter is 120mm. Assuming uniform pressure
distribution, find the total spring load pressing the plates together to transmit 20kW at 1440
rpm. Assume co-efficient of friction as 0.3. Find the total spring load and uniform pressure.

(9 Marks)
Part B

4) a) Identify the diameter of shaft subjected to bending moment.(2 Marks)

b) Design a shaft to transmit 40 hp at 1200 rpm from a motor. The shaft is fitted on two bearings
located 6m apart. Two pulleys A & B of diameters 350 mm and 500 mm are fitted on the shaft.
The position of pulley A is 2.5 m to the right of left hand bearing and transmits maximum of25 hp.
The other pulley is located 2 m to the right pulley A and it transmits the remaining power at an

angle of 60 ° with the drive from pulley A. Assume co-efficient of friction = 0.3 and 1 80°.(7
Marks)

P.T.O