Design of Mechanical System - May 2016
MU Mechanical Engineering (Semester 8)
Total marks: --
Total time: -- INSTRUCTIONS
(1) Assume appropriate data and state your reasons
(2) Marks are given to the right of every question
(3) Draw neat diagrams wherever necessary
Answer any four of the following1(a) What is morphology? Explain seven phases of morphology. 5 marks
1(b) Classify the wire ropes base on twisting of wires in a stand and state their specific use. 5 marks
1(c) Why cleaning of the belt is necessary for belt conveyor? List down the usual types of cleaners. 5 marks
1(d) State the significance of specific speed and NPSH in the design of centrifugal pump. 5 marks
1(e) Explain why an I-section with Ixx ≤ 4 Iyy is selected for connecting rod of I.C. engine. 5 marks
2 An EOT crane is to be deigned for the following specifications:
Lifting capacity: 150 KN
Hoisting speed: 8 m/min.
Span : 10m
Class : II
(i) Select suitable type and size of the wire rope to last for about 12 months.
(ii) Select a standard hook and check for stresses induced at most critical section.
(iii) Design the cross piece and side plates
(iv) Select a suitable motor for hoisting mechanism. 5 marks
3(a) A 20° toughing belt conveyor has the following specifications:
Material to be conveyed: lime stone
Maximum lump size: 100mm
Capacity: 300 TPH
Centre distance: 60 m
(i) Determine the width, number of plies and the thickness of the belt.
(ii) Select a proper motor for the conveyor.
(iii) Design the drive pulley along wih its shaft and also select its bearings 5 marks
3(b) Explain system concepts in design with suitable examples. 5 marks
4 A single cylinder four stroke cycle diesel engine develops 12kW brake power when operating at 1000 rpm. Design the following components:
(i) Determine bore and stroke of the engine
(ii) Design cylinder head and wet liner
(iii) Design piston, piston rings and piston pin.
(iv) Selecting material and design stresses, determine cross-section of the connecting rod. 5 marks
5 Design a centrifugal pump (with layout) for the following specifications
Static suction head: 3m
Length of suction pipe: 10m
Static delivery head: 20m
Length of delivery pipe: 35m
Discharge: 3000 lpm.
Fluid to be pumped is water at room temperature. Design should include selection of motor, design of impeller, impeller shaft, volute casing. 5 marks
6(a) It is required to design gear pump for flow of 50 LPM and pressure 30 bar. The pump is to be driven from and electric motor by direct coupling. The design should include the design of gears, driver shaft and its bearings. 5 marks
6(b) A three-stage, twelve speed gear box is to be designed for spindle speeds varying between 50 r.p.m. and 3000 r.p.m. The second stage consists of three speed steps.If the gear box is driven by 7.5 KW, 1440 r.p.m. electric motor:
(i) draw the speed diagram and
(ii) draw the gearing diagram.
Assume same module for all gears 5 marks