Essential Capabilities Every Monitoring and Diagnostic System Must Have

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A Straightforward Guide to Extruder Train Diagnostics

Monitoring takes place on the gearboxes of the extruder, melt pump (gear pump), pelletizer, dryer and associated motors. All critical bearings and gear wheels must be monitored to detect and identify impending failures at an early stage and avoid costly downtime. For this specialized application, there is no “one-system-fitsall” solution. Several factors make extruder train monitoring a unique challenge:

• Variability in load and vibration amplitude due to process changes
• Wide range of shaft speeds in gearboxes due to the many stages of gear reduction
• High number of different faults to track in complex gearboxes
• Variable-speed operation of the melt pump

So what factors are essential for effective extruder train diagnostics? This document will guide you through the most challenging aspects operators face when selecting a system and vendor, with practical advice to help you invest wisely in a system truly meeting your requirements.

The High Cost of Doing Nothing

With a price tag up to $5 million per gearbox, plus another $5 million per extruder, it is easy to see why extruder trains in petrochemical applications qualify for permanent monitoring and diagnostics. The average MTBM of extruder train machinery for most plastic grades is three years (MTBM is shorter for grades with higher abrasiveness). Unforeseen machine stops not only stress maintenance resources, but can also result in production losses of up to $500,000 per day for each extruder. When the stakes are this high, every extruder train needs a dedicated monitoring system.