1) A lubricant is necessary to
run the machine smoothly taking least load
run the machine quickly
stop the machine immediately
produce workpiece of greater accuracy
2) The general ratio of soluble oil and water used as a coolant is
10:1
1:10
1:20
20:1
3) The best example for semi-liquid lubricant is
grease
graphite
castor oil
lard oil
4) The best example for gravity feed lubrication is
grease gun
ring lubricator
tell-tail lubricator
wick feed lubricator
5) The most common type of cutting fluid used in almost all the machining operations is
water
lard oil
soluble oil
compressed air
6) Fire point is
the temperature at which an oil gives off sufficient vapour to burn it continuously when ignited.
the temperature at which an oil will cease to flow when cooled.
the lowest temperature at which an oil gives off sufficient vapour to support a momentary flash without actually setting fire.
the temperature at which fire is produced
7) Graphite is a
liquid lubricant
semi-liquid lubricant
solid lubricant
none of the above
8) The best example of splash lubrication is
ring lubricator
wick feed lubricator
grease gun
pump lubricator
9) Slideways of a machine is frequently lubricated by
oilcan
grease gun
ring lubricator
wick feed lubricator
10) Which one of the following is the reason that tap water is not preferred as a coolant on machine tools?
It decreases the cutting action of the tool
Danger of corrosion
It has an insufficient cooling effect
Due to the high cooling effect, the cutting edges of the tool break off
11) Which one of the following frictions occurs in an un-lubricated journal bearing?
Sliding Friction
Rolling friction
Fluid Friction
Dry Friction
12) In which one of the following materials no cutting oil is used when drilling?
Tool steel
Grey cast iron
Copper
Aluminum
13) The effective cutting of steel with hand hacksaw, which one of the following coolants is suitable?
Cutting oil
Grease
Lard oil
Kerosene oil
14) Which among the following is NOT the purpose of grease?
Carry away heat produced in bearing
Prevent metal-to-metal contact and reduce friction
Prevent entry of foreign material i.e. dust, dirt etc. in the bearing
Provide a cushion to load and shocks
15) Which one of the following is NOT the property of a good lubricant?
No change in viscosity due to variation in temperature.
Reduces friction between machine parts.
Takes up the surface pressure between sliding parts.
Becomes thicker after prolonged use.
16) The most important quality of any lubricant is
viscosity
specific gravity
specific heat
emulsification
17) Which one of the following is the best way for preparing an emulsion?
Mix soluble oil and water by pouring both simultaneously
Add water to the soluble oil
Add soluble oil to the water
None of the above
18) Which one of the following is a common method for applying cutting fluid on the tool point?
With high-pressure jet
With a brush
With an oil can
Either ‘b’ or ‘c’
19) While machining cast iron, the coolant used should be
dry air
kerosene
machine oil
soft water
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