Series OSS Code No. 102
ENGINEERING SCIENCE
(Common for Automobile Tech., Structure & Fabrication and Air Conditioning & Refrigeration)
(Theory) Paper I
Time allowed : 3 hours Maximum Marks : 70
PART I
ENGINEERING DRAWING 40
Note : Attempt all questions.
1. A regular pentagonal pyramid, base side 30 mm, axis 80 mm long, is resting on its base on H.P., having a side of the base parallel to V.P. and nearer the observer. It is cut by a section plane, parallel to H.P. and passing through the midpoint of the axis. Draw its sectional top view and front view. 15
2. A cube of 40 mm side, is resting on one of its square faces on H.P., having a side of that face parallel to V.P. It is cut by a section plane perpendicular to V.P., inclined at 45° to H.P. and passing through a point on the left vertical edge, 20 mm above H.P. Draw the development of lateral surfaces of the truncated cube. 15
3. Sketch free hand top view and sectional front view of a single riveted double cover butt joint with a diameter of rivet as 16 mm. Give other dimensions also. 10
OR
Sketch free hand front view, upper half in section, of a flanged coupling, having a shaft diameter of 35 mm. Give all other dimensions. 10
PART II
WORKSHOP TECHNOLOGY 30
Note : Attempt any three questions.
4. Explain the process of gas welding. Give the equipment, used in this type of welding. 10
5. Explain resistance welding. For what type of work, do we use seam welding? Explain by examples. 10
6. What is the function of coatings on materials ? Give examples of metallic and non-metallic coatings along with their applications. 10
7.Compare the properties of thermoplastics and thermosetting plastics. Give applications of each. 10
8. Write short notes on any two of the following : 5,5
(i) Anodizing
(ii) Defects in welding
(iii) Gas welding techniques
(iv) Soldering