How is the viscosity of lubrication oil described?

The viscosity of lubrication oil is described specifically by a number that indicates its flow characteristics. Viscosity is a measure of a fluid's resistance to flow; it reflects how thick or thin the oil is. The higher the viscosity number, the thicker the oil, which means it flows more slowly. Conversely, a lower viscosity number indicates a thinner oil that flows more easily. In practical terms, this is important for ensuring that the lubricant can adequately lubricate engine components under various operating conditions, as the right viscosity ensures optimal performance and protection.

Using measurements such as the Society of Automotive Engineers (SAE) viscosity grading, oils are classified not just by their viscosity score but also by operational temperatures, additives, and how they perform at different temperatures. This numerical representation is critical for manufacturers and engineers when selecting appropriate lubricants for specific applications, especially in machinery and automotive contexts.