Which of the following operations will commonly require the use of lube oil samples?

The operation that commonly requires the use of lube oil samples is monitoring turbine operations. Lube oil plays a crucial role in the performance and reliability of gas turbines, as it is used to lubricate moving parts, reduce friction, and help manage heat. By analyzing lube oil samples, technicians can assess the condition of the oil and the wear rates of engine components. Contaminants or excessive wear particles found in the oil can indicate potential issues within the turbine, allowing for timely maintenance or repairs to prevent catastrophic failures.

In contrast, while portable equipment checks, industrial washing, and combustion tests are essential maintenance practices, they do not typically involve monitoring the condition of lube oil directly. Portable equipment checks often focus on operational readiness and safety, industrial washing pertains to cleaning and maintenance tasks, and combustion tests evaluate the efficiency of the combustion process. None of these operations specifically utilize lube oil samples for condition monitoring or assessment of turbine health.