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Why is lubrication important in engines and other machines?
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Six simple machines for transforming energy into work.
Lubrication is essential in engines and machines primarily to reduce friction and wear between moving parts. By interposing a film between sliding surfaces, lubricants can reduce friction by up to 200 times compared to unlubricated surfaces.12
The primary functions of lubrication include:
- Wear Reduction: Lubricants prevent abrasive and solid-to-solid contact by maintaining a protective film that separates surface asperities.1
- Temperature Control: They assist in cooling by reducing friction and carrying away generated heat. In engines, oil must flow at an appropriate rate to effectively dissipate this heat.12
- Corrosion Prevention: Lubricants protect metal surfaces from corrosion by acting as a preservative when machinery is idle and by coating parts with protective films—often containing additives—during operation.12
- Contaminant Management: In systems like gasoline engines, lubricants help disperse deposit-forming gums and solid contaminants, which are then managed by oil filters.2
Proper lubrication requires selecting a substance with the correct viscosity and chemical properties to match the specific operating conditions of the machine.12