Oilers/Plant Tenders (HHC) Civil Service Practice Exam

What is essential for a turbine oil to effectively perform its lubricating job?

1. High density

2. Proper viscosity

3. Low volatility

4. High thermal conductivity

The correct answer is: Proper viscosity

For a turbine oil to effectively perform its lubricating job, proper viscosity is critical. Viscosity is a measure of a fluid’s resistance to flow and is an essential property for lubricants because it impacts the oil’s ability to form a film between moving surfaces. This film prevents metal-to-metal contact, reducing wear and friction, which are crucial for the efficient operation and longevity of turbine machinery. The viscosity needs to be appropriate for the operating temperature range; if the oil is too thick, it may not flow properly at lower temperatures, leading to inadequate lubrication. Conversely, if the oil is too thin at higher temperatures, it might not provide sufficient protection. Therefore, ensuring that the turbine oil has the correct viscosity ensures that it retains its lubricating properties under varying operational conditions. While other properties like density, volatility, and thermal conductivity play roles in lubricant performance, they do not directly influence the ability of the oil to maintain an effective lubricating film as viscosity does. High density might aid in stability of the oil, low volatility helps in reducing loss of oil due to evaporation, and high thermal conductivity can assist in heat dissipation, but none are as fundamental to lubrication as proper viscosity.