Asset Selection in Oil Analysis Services 

Analysing every lubricated asset within a process is impractical, and some data will likely provide little value. However, selecting which assets should be analysed for an oil analysis programme can be a complex task. 

A straightforward approach through auditing can help establish a reasonable list. Such an audit should consider four key factors: criticality, environment, safety, and cost. 

Any asset that is critical to overall operations must be analysed — that is, any asset whose slowdown or failure would cause a knock-on effect throughout the rest of the operations. Even those assets that are duplicated but whose output is required continuously should be considered. 

Any asset operating in a contaminated environment, whether due to moisture, particulates, or both, is a strong candidate for analysis. Even systems fitted with filters and breathers are not exempt, as these protective devices can fail unexpectedly. 

Any asset whose failure could result in harm to personnel should also be subject to analysis. For example, a retaining system on a conveyor belt or speed control mechanisms on a hydraulic system. If asset failure could cause injury, and such failure can be mitigated by maintaining fluid condition, then that asset should be analysed. 

Any asset whose failure or loss of functionality would involve significant cost — whether due to downtime, parts, or labour — should be included in the programme. In some cases, difficult access or remote location may alone justify sampling. Assets with low-cost but recurrent failures may also be considered. 

Asset Selection 

Analysis should be considered for assets operating under a reactive maintenance philosophy, such as oil-lubricated electric motors or centrifugal pumps that fail due to sudden wear. 

The suitability of analysis for small, reliable assets should be evaluated — particularly where sampling would require a full oil refill or nearly complete drainage. A similar exception may be made for reliable assets with regular oil drain intervals but difficult analysis access — for example, gearboxes on cooling towers requiring shutdown for access. 

The value of oil analysis does not necessarily lie in directly preventing a failure, but rather in reducing its severity. After all, fluid will always degrade over time and should therefore be monitored to ensure it degrades in a predictable way, allowing for proper replacement or reconditioning. 

Contamination and wear will always be present, but action should only be taken when an abnormal trend is detected, or an established limit is exceeded. For this reason, samples must be taken at a frequency that allows such changes to be detected. 

Assets with recurring failures between sampling intervals should be analysed more frequently, while those reaching their drain or overhaul intervals without issues can be sampled less frequently — or even excluded from the programme. The goal of any tool is to be used when and where it is most effective. 

Establishing a suitable list of assets ensures that oil analysis is applied effectively and efficiently, thereby contributing to improved operational reliability. 

Author: Evan Zabawsk