Sample evaluation test

Question 1

State the purpose of the baffle plates in a reservoir
3 marks

Answer 1

A baffle plate must be fitted to prevent turbulence, allows foreign material to settle to the bottom and allows oil to rid of trapped air.

Question 2

Explain, giving one reason, the purpose of a cooler
3 marks

Answer 2

When air is compressed it rises in temperature also heat is generated in the bearings. Should the temperature of oil rise too high temperature cracking could occur and lubricating properties altered.
3 marks

Question 3

State one purpose of lubrication.
2 marks

Answer 3

When the surface of two bodies are in contact, the force of friction will resist motion between them.
Lubrication is necessary to overcome the effects of the friction forces.
Friction causes energy to be wasted in the form of heat and causes the rubbing surfaces to wear.
To separate the surfaces in contact and thus reduce the effect of friction it can never be eliminated.