1. Define the following:

Ductility

Toughness

Creep

Normalising

Tempering

Coupling

Joint

Compare the stress-strain curve for ductile material and brittle material.

Select suitable materials for the following cases, indicating the reason:

Nut of a heavy duty screw jack

Low speed line shaft coupling

3. Discuss the design procedure of spigot and socket cotter joint.

4. Design a protective type of cast iron flange coupling for a steel shaft transmitting 15 kW at 200 rpm and having an allowable shear stress of 40 N/mm^2. The working stress in the bolts should not exceed 30 N/mm^2. Assume that the same material is used for shaft and key and that the crushing stress is twice the value of its shear stress. The maximum torque is 25% greater than the full load torque. The shear stress for cast iron is 14 N/mm^2.

What do you mean by torsional rigidity and lateral rigidity? Explain.

How is the shaft designed when it is subjected to twisting moment only?

Show by neat sketches the various ways in which a riveted joint may fail.

A plate 10 cm wide and 1 cm thick is to be welded to another plate by means of double parallel fillets. The plates are subjected to a static load of 80 N. Find the length of the weld, if the permissible stress in the weld does not exceed 5·5 N/mm^2.

7. Derive an equation for the torque required to raise load on square threaded screws.

8. Write short notes on any four of the following:

Self Locking Screws

Caulking and Fullering

Oldham Coupling

Riveted Joint

Elastic Constants

Alloy Steel