Which is a common lube oil viscosity range in Saybolt units?

The correct answer is the viscosity range of 500-1000 SSU, which indicates a common range for lubricating oils used in marine engines. Saybolt Universal Seconds (SSU), a measure of kinematic viscosity, is important in determining the flow characteristics of lubricating oils.

Oils within this viscosity range provide adequate lubrication under the operating conditions found in most marine systems, ensuring that engine components are effectively lubricated while minimizing friction and wear. It is essential for the oil to maintain proper viscosity at varying temperatures and pressures during operation, contributing to overall engine efficiency and reliability.

Lube oils that fall outside this range, such as those with a viscosity of 100-200 SSU, may not provide sufficient lubrication under high-load conditions. Oils with a viscosity of 300-500 SSU or 1000-1500 SSU could also be impractically thick or too thin, respectively, for effective use in the engines under typical operational parameters. Therefore, the 500-1000 SSU range is widely recognized within the marine industry as suitable for various systems, balancing protection and performance.