Online Monitoring Case Study - Gearbox Defect

Applied Diagnostics Ltd - Precision with Pride

Introduction

This high speed processing machine is used to package food into their individual portions. The critical drive components on these units comprise of 2 motors, 2 gearboxes and a high sped spindle shaft. Due to interlocked doors there is poor access for maintenance and routine monitoring, therefore an on-line monitoring system was fitted to alert engineers to any potential maintenance issues such as bearing wear or gear problems.

Plant Dashboard – ‘Status at a Glance’

A plant dashboard was designed for this client so that that they have the condition of all 26 machines displayed on one screen. By clicking on the relevant machine the latest vibration readings are displayed in the bottom left hand corned of the dashboard. By looking at the associated trend the client can see how quickly the problem is developing and plan in maintenance accordingly.

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4A Packager Bearing Trend

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Actions / Conclusions

Following the installation and configuration of the on-line system the benefits were immediately apparent. The following information relative to packager condition was available allowing a Pro-Active maintenance strategy to be adopted:

  1. The 2nd Gearbox reading was extremely high, possibly due to lack of gear or bearing wear.
  2. The 2nd Drive Motor bearing was extremely high, possibly due to bearing wear.
  3. All other packager drive components were in good working order.

The on-line system was configured to react in the following manner:

  1. Local Panel Alarm illuminated to alert operators to packager 4A maintenance issue.
  2. Dashboard highlighted a maintenance issue on packager 4A to the site engineers, including Gearbox 2 and Motor 2 bearing vibration levels.
  3. E-mail sent to Applied Diagnostics engineers to alert them to packager 4A maintenance issue, Gearbox 2 and Motor 2 bearing vibration levels.

The following corrective maintenance actions were taken following the received alerts:

  1. Applied Diagnostics engineers collected frequency spectrum data from the local panel vibration outputs. A severe gear defect and loose motor bearing defect were diagnosed.
  2. Site engineers replaced gearbox 2 and refitted a new bearing in motor 2, these maintenance actions reduced the trend to acceptable levels.

Gear/Motor Bearing Damage Photos

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