List five factors to consider when choosing a lubricant.

Here are the solutions to Activity 3.3:

1. Match the property in the left column to the correct description in the right column:

• Flash point: Minimum temperature at which an oil will ignite momentarily.
• Thermal stability: To resist breakdown at high temperatures.
• Fire point: Lowest temperature at which an oil will ignite and burn for at least five seconds.
• Oiliness: Maintaining an unbroken lubricating film between rubbing surfaces.
• Viscosity: Gives an indication of the thickness or thinness of an oil.

2. List five factors to consider when choosing a lubricant:

• Operating temperature
• Operating pressure/load
• Speed of moving parts
• Environmental conditions (e.g., presence of water, dust)
• Type of machinery/application