1. Select the most appropriate answer

Resilience of a material is important when subjected to

fatigue

wear and tear

shock loading

inertia loading

When two shafts Me neither parallel nor intersecting, power can be transmitted by using

a pair of spur gears

a pair of helical gears

an Oldham's coupling

a pair of spiral gears

Size of the gear is generally specified by

pitch circle diameter

working depth

module

tooth thickness

In a single reduction, a large velocity ratio is required. The best transmission is

spur gear drive

helical gear drive

bevel gear drive

worm gear drive

A connecting rod should be

strong in buckling about x-axis only

strong in buckling about y-axis only

equally strong in buckling about both x-axis and y-axis

more strong in buckling about x-axis than that about y-axis

Two mating spur gears have 70 and 30 teeth respectively. Corresponding to a module pitch 5 mm, the centre to centre distance between the gears will be

125 mm

250 mm

375 mm

500 mm

In the formulation of Lewis equation for toothed gearing, it is assumed that tangential tooth load acts on the

pitch point

tip of tooth

root of the tooth

whole face of the tooth

2. A compressor running at 400 rev/min is driven by a 15 kW, 1600 rev/min motor through 14 full depth gears. The centre distance is 0·375 m. The motor pinion is to be of C-30 forged steel hardened and tempered, and the driven gear is to be of cast steel. Assuming medium shock condition:

Determine the module, the face' width, and the number of teeth on each gear.

Check the gears for dynamic load and wear:

Design the drive completely.

3. Two shafts 0·30 m apart transmitting 20 kW are to be connected by a steel pinion meshing with cast iron gears. The velocity ratio is to be 3 to 1 and the smaller gear is to run at 600 rev/min. The ultimate strength of the material for the gear material is 168 MPa and the factor of safety is 4. Design the arms. for the gear and find the diameter of the gear shaft.

4. Determine the safe power which can be transmitted by a pair of helical gears, 20-degree full depth, 25-degree helix, having a normal module of 5 mm, Both the gears are made of forged C-30 steel and have a face width of 77 mm. The pinion speed is 2000 rev/min and it has 20 teeth. The velocity ratio is to be 5 to 1.

5. Determine the main dimensions of a multi-collar thrust bearing for a propeller shaft of a 460 kW power marine oil engine. The engine runs at 220 rev/min, the shaft diameter is 0·15 m and the propeller has a pitch of 2·50 m. Assume a slip of 25%.

6. A journal bearing is proposed for a centrifugal pump. The diameter of the journal is 0·15 m and the load on it is 38 kN and its speed is 900 rev/min. Complete the design calculation for the bearing.

Discuss the effect of number of cylinders on the performance of an I.C. Engine.

What is the effect of stroke to bore ratio on the design of an I.C. Engine? Explain.