Lubrizol

Question 1

What is a lubricant?

Answer 1

Is a substance, usually organic, introduced to reduce friction between surfaces.

Question 2

What properties must a lubricant possess?

Answer 2

• A high boiling point and low freezing point (in order to stay a liquid over a wide range of temperatures.
• High viscosity index.
• Thermal stability.
• Hydraulic stability.
• High resistance to oxidation.
• Corrosion prevention.

Question 3

What are lubricants composed of?

Answer 3

Typically contain 90% base oil (mineral oils) and less than 10% additives. Group 1 - 5.

Question 4

Give a few examples of base oil.

Answer 4

Vegetable oils such as esters, silicones and fluorocarbons. Can be synthetic or minerals.

Question 5

What do additives do?

Answer 5

Increase viscosity, improve viscosity index, have resistance to corrosion/oxidation. They all have a life span.

Question 6

How many additives are contained within lubricants?

Answer 6

As many as 10 additives.

Question 7

Give a few examples of additives.

Answer 7

• Antifoaming agents which lower surface tension in order to discourage foam formation.
• Viscosity index improvers (VIIs) allowing lubricants to remain viscous at higher temperatures. This also means high resistance (thick).
• Antioxidants: suppress the rate of oxidative degradation of the hydrocarbon within the lubricant.
• Corrosion inhibitors, usually alkaline materials.
• Anti-scuffing additives against extreme pressures.

Question 8

Name 5 types of lubricants.

Answer 8

• Mineral oils, derived from crude oil.
• Synthetic oils, produced from synthetic hydrocarbons.
• Solid lubricants, including PTFE, inorganic solids such as graphite, metal alloys used as grease additives.
• Aqueous lubrication, PEG which are strongly hydrated brush polymers.
• Bio Lubricants, derived from vegetable oils and other renewable sources.

Question 9

How does a lubricant transfer heat?

Answer 9

Both gas and liquid lubricants can transfer heat. Liquid lubricants are much more effective because of their high specific heat capacity. The liquid is constantly circulated to and from a cooler part of the system. The drawback is when a system suddenly shuts down, the oil can immediately oxidise and clog the oil ways.

Question 10

Disposal and environmental impact of lubricants.

Answer 10

40% of lubricants are released into the environment. Recycled, burned or disposed into landfill waste. Regulations in place for a threshold level of lubricant that may be present in waste streams. Burning generates airborne pollution and toxic materials, mainly heavy metal compounds. Landfill sites handle the toxic ash and specialised facilities handle airborne pollution. Other disposal methods include run-off from roadways, accidental spillage or natural disasters. The additives added to lubricants are considered to be toxic and can be harmful to the environment.

Question 11

What is the calorific value of fuel?

Answer 11

It is the total quantity of heat liberated when a unit mass/volume of fuel is completely burnt.

Question 12

What is higher calorific value (HCV)?

Answer 12

It is the total amount of heat produced when a unit of mass/volume has been completely burnt and the products of combustion have been cooled to room temperature.

Question 13

What is lower calorific value (LCV)?

Answer 13

It is the heat produced when a unit of mass/volume of fuel is burnt completely and the products are permitted to escape.

Question 14

Where are natural/primary fuels found?

Answer 14

In nature, such as wood, peat, coal, natural gas and petroleum.

Question 15

Properties of an ideal fuel.

Answer 15

• High calorific value.
• Moderate ignition temperature.
• Low moisture content.
• Easy to transport.
• Combustion must be controlled.
• Should burn in air.
• Low cost.

Question 16

Explain thermal efficiency

Answer 16

Measure of thermal energy such as an internal combustion engine. It is the fraction of energy added by heat that is converted to net work output (performance).

Question 17

How to improve internal combustion engine efficiency?

Answer 17

• Turbochargers, is an exhaust gas recovery device that increases boost air pressure thereby optimizing combustion. It increases efficiency by 7-8%.
• Using the correct viscosity of lubricating oil, as visocosity is linked to friction.
• Direct fuel injection, increasing efficiency by 11-13%.

Question 18

What is heat?

Answer 18

Heat is a form of energy that affects the temperature of objects by changing movement of atoms/molecules.

Question 19

What is fuel?

Answer 19

Fuel is a combustible substance, containing carbon as a main constituent, gives large amount of heat and work upon burning.

Question 20

Secondary fuels?

Answer 20

Prepared fuels such as kerosene, diesel, petrol, bio-gas, natural gas, water gas, charcoal, coke.

Question 21

Ignition temperature?

Answer 21

The lowest temperature at which the fuel starts burning smoothly. Gases - Low, Solid - High.

Question 22

Non-combustible matter:

Answer 22

Does not take part in combustion process, it remains in the form of ash, and it also reduces the heating value.

Question 23

Synthetic oil vs. Mineral oils

Answer 23

• Mineral oil is a petroleum product from the ground, whereas synthetic oils are made in controlled environment to get a uniformed product.
• Mineral oils come as different sizes whereas as synthetic oil consists of the same sized particles.

Question 24

What things are to be considered with oil?

Answer 24

• Thickness.
• Size matter (particles) of lubricant.
• Viscosity.
• Flash point.
• Oiliness.

Question 25

What is viscosity?

Answer 25

It is a measure of internal resistance of liquid during its flow, units are in cp (centipose).

Question 26

What happens to the lubricant when pressure increases?

Answer 26

As pressure increases, viscosity increases.

Question 27

Functions of oil to the engine.

Answer 27

- Cools - Cleans - Lubricates - Protects

Question 28

What does cooling mean?

Answer 28

Lubricant removes heat from the engine system, by absorbing it and releasing it to the air or the jacket cooling system.

Question 29

What does cleaning mean?

Answer 29

Detergent breaks down slime and sludge, to allow for easy circulation of liquid and to improve heat transfer capacity. (filter can be used)

Question 30

What does lubrication mean?

Answer 30

To reduce friction and reduce the amount of heat produced. Help keeps the engine cool.

Question 31

What to avoid within the engine system?

Answer 31

Water within the oil system, it has a low viscosity.

Question 32

What is oil grade?

Answer 32

Single grade, multi grade (most commonly seen), 15W-40, Low temp characteristics then high temp characteristics, W = Winter.

Question 33

Why do you want to work at Lubrizol?

Answer 33

I want to work with like-minded people on the revolutionary technology lubrizol is working towards. I strongly believe I share the same culture and values and would fit in very well with the development team.

Question 34

Why a placement year?

Answer 34

I want to have the opportunity to improve my skills I have already developed in a laboratory setting, and I want to understand what working a sustainable level is in an industrial setting. The experience will give me a better understanding of the my career choice once I graduate university.

Question 35

What are good safety considerations?

Answer 35

Precautions include the use of toxic chemicals and correct handling of them, completing a risk assessment prior to entering the lab and handling the chemicals, also a good understanding of disposal of chemicals e.g. halogenated waste or non-halogenated waste.

Question 36

Explain a time you were in a difficult situation and how did you overcome this?

Answer 36

Difficult colleague, approached my colleague politely, once my input was ignored I took charge and suggested to my supervisor to increase security within the fitting room department. As a result, the issue was resolved in a calm manner with great understanding on both sides and this also helped me improve my leadership skills.