Subject Code:160201
GUJARAT TECHNOLOGICAL UNIVERSITY
--- Content provided by FirstRanker.com ---
SEMESTER-VI(OLD) - EXAMINATION - SUMMER 2019
Subject Name: Automobile Component Design
Time:10:30 AM TO 01:00 PM
Total Marks: 70
Instructions:
--- Content provided by FirstRanker.com ---
- Attempt all questions.
- Make suitable assumptions wherever necessary.
- Figures to the right indicate full marks.
Q.1 (a) Explain the working of valve gear mechanism for a given I.C. engine with neat sketch. [07]
(b) A helical cast steel gear with 30° helix angle has to transmit 35 kW at 1500 r.p.m. If the gear has 24 teeth, determine the necessary module, pitch diameter and face width for 20°full depth teeth. The static stress for cast steel may be taken as 56 MPa. The width of face may be taken as 3 times the normal pitch. What would be the end thrust on the gear? The tooth factor for 20°full depth involute gear may be taken as 0.154-0.0912 / Te , where TE represents the equivalent number of teeth. [07]
--- Content provided by FirstRanker.com ---
Q2 (a) Explain the designing procedure of multi speed automobile gear box [07]
(b) A bronze spur pinion rotating at 600 r.p.m. drives a cast iron spur gear at a transmission ratio of 4 : 1. The allowable static stresses for the bronze pinion and cast iron gear are84 MPa and 105 MPa respectively. The pinion has 16 standard 20° full depth involute teeth of module 8 mm. The face width of both the gears is 90 mm. Find the power that can be transmitted from the standpoint of strength. [07]
OR
(b) A shaft rotating at constant speed is subjected to variable load. The bearings supporting the shaft are subjected to stationary equivalent radial load of 3 kN for 10 per cent of time, 2 kN for 20 per cent of time, 1 kN for 30 per cent of time and no load for remaining time of cycle. If the total life expected for the bearing is 20 x 106 revolutions at 95 per centreliability, calculate dynamic load rating of the ball bearing. [07]
Q3 (a) Explain the following terms in relation with rolling contact bearing 1)Equivalent load , 2)Bearing life. [07]
--- Content provided by FirstRanker.com ---
(b) A four stroke diesel engine has the following specifications : Brake power =5 kW ; Speed = 1200 r.p.m. ; Indicated mean effective pressure = 0.35 N/ mm 2 ; Mechanical efficiency = 80 %. Determine: 1. bore and length of the cylinder ; 2. thickness of the cylinder head ; and 3. size of studs for the cylinder head. [07]
OR
Q3 (a) Determine the beam strength and face width of helical gears, also explain the following 1) Helix angle 2) Axial pitch 3) Normal Pitch [07]
(b) Design a cast iron piston for a single acting four stroke engine for the following data: Cylinder bore = 100 mm ; Stroke = 125 mm ; Maximum gas pressure = 5 N/mm2 ; Indicated mean effective pressure = 0.75 N/mm2 ; Mechanical efficiency = 80% ; Fuel consumption = 0.15 kg per brake power per hour ; Higher calorific value of fuel =42 x 103 kJ/kg ; Speed = 2000 r.p.m. [07]
--- Content provided by FirstRanker.com ---
Q.4 (a) Explain strength rating and wear rating of worm gears [07]
(b) Design of the crankshaft when the crank is at the dead centre for the following data: Bore =400 mm ; Stroke = 600 mm ; Engine speed = 200 r.p.m. ; Mean effective pressure = 0.5 N/mm2; Maximum combustion pressure = 2.5 N/mm2; Weight of flywheel used as a pulley = 50 kN; Total belt pull = 6.5 kN. When the crank has turned through 35° from the top dead centre, the pressure on the piston is IN/mm2 and the torque on the crank is maximum. The ratio of the connecting rod length to the crank radius is 5. Assume any other data required for the design. [07]
OR
Q.4 (a) Explain Design Criteria of intake manifold and exhaust manifold [07]
(b) A side or overhung crankshaft for a 250 mm x 300 mm gas engine. The weight of the flywheel is 30 kN and the explosion pressure is 2.1 N/mm2. The gas pressure at the maximum torque is 0.9 N/mm2, when the crank angle is 35° from I. D. C. The connecting rod is 4.5 times the crank radius. Design of crankshaft when the crank is at the dead centre [07]
--- Content provided by FirstRanker.com ---
Q.5 (a) Discuss causes of failure in rolling contact bearing. [07]
(b) Explain types of worm gears & Efficiency of worm gears. [07]
OR
Q.5 (a) What do you mean of creep? Explain Hot Working Process [07]
(b) Differentiate between dry and wet liner. Describe the Ideal properties required for engine Piston material [07]
--- Content provided by FirstRanker.com ---
This download link is referred from the post: GTU BE 2019 Summer Question Papers || Gujarat Technological University
--- Content provided by FirstRanker.com ---