The three tools of predictive maintenance in lubrication
- In-service oil analysis: detects wear, contamination, and lubricant degradation. Scope: any oil-lubricated equipment. Cost: €30-80/analysis.
- Infrared thermography: detects hot spots in bearings, motors, and electrical connections. No equipment shutdown required. Cost: camera (€1,000-5,000) or external service.
- Vibration analysis: detects imbalance, misalignment, play, and bearing failures. High diagnostic specificity. Cost: equipment + training or external service.
Oil analysis as a first-line tool
Oil analysis is the easiest predictive maintenance tool to implement without investment in own equipment. An external laboratory collects the sample, analyses it, and issues a traffic-light report in 48-72 hours.
The key is consistency: same sampling points, same frequency, same laboratory. The trend is more valuable than any isolated value. An iron level of 45 ppm may be normal for one piece of equipment or indicate accelerated wear — only the history tells you.
How to structure the programme: three criticality levels
Not all equipment deserves the same investment in predictive maintenance. Classification by criticality determines which tools and frequencies to apply:
- Level A (critical): equipment whose stoppage halts production or involves risk. Quarterly oil analysis + semi-annual thermography + monthly vibration.
- Level B (important): equipment with redundancy or moderate economic impact. Semi-annual oil analysis + annual thermography.
- Level C (secondary): equipment with spare in stock or limited impact. Preventive maintenance by hours or calendar without systematic analysis.
The real cost of not doing predictive maintenance
An unplanned stoppage of a production line running at 1,000 units/hour with a contribution margin of €2/unit generates €2,000/hour in lost production. If the stoppage lasts 8 hours (average repair time for a reducer without prior diagnosis), the loss is €16,000 — not counting the cost of urgent repair or the effect on the customer.
A quarterly oil analysis programme for that reducer costs €320/year and can detect the problem 4-8 weeks before failure, allowing the repair to be scheduled for a weekend. The return on investment is immediate.
Lubrication-based predictive maintenance does not require a large maintenance department or a large budget. It requires consistency: same points, same frequency, same laboratory, and someone who reads the reports and makes decisions. With that, most plants can reduce their unplanned stoppages by 30-60% in the first year.
Design a predictive maintenance programme