Book 2 Chapter 30: Lubrication Flashcards
Which of the following are reasons for using lubrication?
A) Corrosion reduction
B) Temperature control
C) Shock absorption
D) All of the above
D) All of the above
Explain how a lubricant is used to control the metal temperatures in rotating equipment.
The lubricant reduces the heat produced by reducing friction. In addition, it may be used to carry off heat from the bearing surfaces. In the latter case, a common arrangement is to circulate generous quantities of the lubricant to the bearing where it picks up heat. The lubricant is then cooled in a heat exchanger before returning to the bearing again.
If an oil has a high viscosity index, this indicated that its viscosity changes _______ with temperature change.
Little
Pertaining to oils, explain what are the flaws and fire points.
Flash point: temperature at which the oil will give off sufficient vapour to ignite momentarily when mixed with air, and exposed to a source of ignition
Fire Point: temperature at which enough vapour is given off to burn continuously
A material that is commonly used as a solid lubricant is:
A) Molybdenum disulphide
B) Tallow
C) Sodium carbonate
D) Molybdate sulphide
E) Lime
A) Molybdenum disulphide
Which of the following purposes of lubrication between two moving metallic surfaces is most important?
A) Temperature control
B) Friction reduction
C) Corrosion reduction
D) Sealing
E) Shock absorption
B) Friction reduction
The viscosity of oil:
1. Is the temperature at which oil will burn
2. Determines the ability of the oil to support a load
3. Will prevent corrosion of bearings
4. Indicates the liquid’s inability to flow
A) 2,4
B) 1,3
C) 2,3,4
D) 1,2,4
E) 3,4
A) 2,4
Viscosity index provides a measure of oil’s tendency to:
A) Resist change due to oxidization
B) Resist changes due to contamination
C) Maintain viscosity due to temperature change
D) Change viscosity due to temperature change
E) Change viscosity under load
D) Change viscosity due to temperature change
A disadvantage of a high flash point oil is:
A) Increase carbon residue
B) Depressed pour point
C) Increased safety of operation
D) Wider range of operating temperatures
E) Low viscosity
A) Increase carbon residue
The instrument at which measures the viscosity of oil at a certain temperature as it flows through a small diameter tube is called a/an:
A) Oil meter
B) A thermometer
C) A pyrometer
D) Saybolt viscosimeter
E) Orifice plate
D) Saybolt viscosimeter
If you desire an oil to flow at a much lower temperature, you would most likely add:
A) Low viscosity oil
B) Pour point depressants
C) A thickening agent
D) A viscosity index improver
E) A dispersant
B) Pour point depressants
Grease is not a suitable lubricant:
A) If corrosion protection is desired during downtime
B) If the atmosphere contains a low of moisture
C) When the atmosphere is dusty
D) In the textile and food industries
E) If a large amount of cooling is desired
E) If a large amount of cooling is desired
The measure of liquid lubricating oil’s ability to resist internal deformation or shear is called:
A) Flash point
B) Neutralization number
C) Pour point
D) Viscosity
E) Viscosity index
D) Viscosity
Greases are a mixture of petroleum oil and:
A) Synthetic oils
B) Carbon powder
C) Soap
D) Paraffin
E) Lard
C) Soap
If an oil’s viscosity changes a great deal with little temperature change, it will then have a:
A) Low pour point
B) Low viscosity index
C) High carbon residue
D) High pour point
E) High viscosity index
B) Low viscosity index
