Punjab Technical University 2005 M.Tech Machine Design TRIBOLOGY ME 502 - Question Paper

TRIBOLOGY ME 502 first Sem May 2k5

Max marks 100

Note: Attempt any 5 ques.. All ques. carry equal marks.

1. (a) what is the basic criterion that is followed for the selection of the roller baring?
(b) What is the effect of abrasion in grinding?
(12,8)

2. (a) explain the kind of contacts i.e. conforming and non-conforming.
(b) Compare the elastic deformation and plastic deformation.

3. (a) describe friction. explain the Tabor’s model of friction.
(b) Write short note on wear of cutting tools and dies.

4. (a) explain the methods to decrease cavitations in bearing.
(b) define the surface energy theory and flash temperature theory . (8,12)

5. A journal bearing Is proposed for a centrifugal pump. The diameter of bearing is 0.2 m and the load on it is 60 kN and its speed is 1000 rev/min. Completer the design computations for the bearing.

6. (a) Derive the Reynold’s formula in 2-D stating the different assumptions used for deriving the identical.
(b) discuss the single penetration of the boundary lubrication. (12,8)

7. (a) discuss in detail the laws of sliding friction. Can you suggest a few laws of rolling friction analogous to those of the sliding friction?
(b) elaborate the various kinds of corrosion wear?

8. (a) define the various methods for the measurement of friction.
(b) Derive and discuss the pressure distribution and load carrying friction forces in oil film.

Earning:   Approval pending.