1. Design a Two-stage spur gear reduction unit with 20° F.D involute teeth. The input shaft is connected to 9.5 kW, 1400 rpm motor through a flexible coupling. The output shaft speed shall be approximately 200 rpm. The gears are made up of plain carbon steel.

• i) Find dynamic load and check for wear load.
• ii) Decide the constructional details of the gear and pinion showing neat sketch.

2. A single stage spur gear box is used to transmit 15 kW power at 1440 rpm of pinion. The desired transmission ratio is 4:1 Assume 20 degree FD involute profile and material C55Mnl for pinion and gear.

• i) Find the module
• ii) Check gear forLewis Dynamic Load
• iii) Check gear for wear strength
• iv) Write Constructional Details

3. Design a helical gear pair for the first stage of gear box having the following specifications.

• Power = 20 kW
• Input speed = 1440 rpm

• Output speed = 90 rpm

  (Design should include, module selection, checking for dynamic Load and contact stresses and construction type and constructional details of gear)

4. Design a pair of helical gears to transmit a power of 36,800 Watts at 30 rps of the pinion. Gear ratio is 4. Helix angle is 15 0 . Teeth is 20 0 full depth. Material used is C50.

5. Design a Bevel gear pair for following specification, rated power = 25kW Input speed = 960 rpm,output speed = 240 rpm,shafting intersecting angle - 75 degree.

6. worm and worm wheel drive are required to transmit power from an electric motor rated at 11KW and 1440 rpm with a reduction ratio of 15. The power is supplied to a belt conveyor which operates for 12 hours per day. Selecting suitable material and stresses, design worm and worm wheel for strength and wear. Do not check for heat dissipation capacity.

7. Design a Worm and worm wheel drive to run a reciprocating feeder at 40 rpm from the motor which run at 1440 rpm and delivers power of 15kW. Also check for thermal criteria.