Coupled oil analysis trending and life-cycle cost analysis for vessel oil-change interval decisions

Extending lube oil-drain intervals is a practical way to save money on engine operating costs. At the same time, there may be increased risk of engine damage with increased drain intervals. The risks and benefits can be difficult to weigh and, as a result, starting an oil-drain interval extension programme can be an intimidating endeavour. This paper combines oil-analysis programme data interpretation and life-cycle cost analysis (LCCA) into a methodology for weighing oil-drain interval options. LCCA has shown decreasing incremental cost savings as oil-drain intervals are further extended, indicating that highly extended drain intervals may not be necessary to reap the majority of available cost benefits. Using oil-analysis property trending with life-cycle cost savings can allow an engine operator to set an hours-based extended drain interval based on projected risks and benefits. This interval is set as the baseline under the protocol, but continual oil analysis is used as a precaution to protect against unpredictable events. This methodology helps to reduce the risk of engine damage and ensure that the most easily attainable cost savings are still captured, making the decision about how to extend oil-drain intervals more approachable.