Lubrication Analysis Supports Grain Processing Reliability

Improving plant reliability and predictability through best-practice lubrication, routine oil analysis and proac- tive maintenance recommendations. A cooker mixer at this site plays a critical role in the grain cooking process, ensuring product remains mobile and evenly heated throughout production.

Failure of the mixer could result in product solidifying within the vessel, requiring costly specialist cleaning, production downtime and significant maintenance intervention. Maintaining the reliability of this asset was therefore essential to plant performance.

For more than two years, AVT Reliability® has supported the site with routine lubrication services, including equipment greasing, oil sampling, oil changes and lubrication best-practice guidance.

Due to the critical nature of the cooker mixer, the asset was included within a structured oil analysis programme. Samples were analysed every six weeks to monitor lubricant condition, additive health, contamination levels and wear metals.

Each report was reviewed by AVT specialists, allowing developing issues to be identified and communicated before they became operational failures.

As part of an ongoing lubrication programme, AVT Reliability® collected routine oil samples from the gearbox every six weeks for laboratory analysis.

Recent reports identified increasing levels of iron wear particles, indicating abnormal internal wear. Following further investigation and inspection, several gearbox teeth were found to be chipped, heavily worn or broken.

The likely root cause was excessive movement caused by a damaged non-drive-end footstep bearing within the vessel, leading to abnormal loading and gear impact. Importantly, routine vibration analysis showed no significant abnormalities, demonstrating the value of oil analysis as an additional condition monitoring technique.

The findings were communicated to site management, allowing corrective action to be planned before the gearbox reached a critical failure condition. Following inspection, the gearbox was removed from service and replaced, with the damaged unit sent for refurbishment and further investigation.

To address the suspected root cause, the non-drive- end footstep bearing was added to the scope of the site’s upcoming summer shutdown, where it will be inspected and repaired or replaced as required.

In addition, the replacement gearbox has been retained within the existing six-week oil analysis programme, enabling AVT Reliability® to closely monitor its condition and verify that wear rates return to normal levels.