What did GE's analytics software find?
On May 12th, the GE SmartSignal solution detected mill bearing temperatures continuing to increase after a mill start while running current was stable. Several thrust and radial bearings increased to temperatures that were 20°F (11°C) – 35°F (19°C) above the model estimate. GE’sIndustrial Performance and Reliability Center (IPRC) was notified immediately and the case was discussed on the weekly monitoring call.
What was the underlying cause?
Upon investigation of the issue, the site discovered a faulty block valve on the cooling water inlet to the lube oil cooler and a failed sightglass flow indicator. The valve was indicating open, despite it being closed, and the sightglass flow indicator was stuck showing flow. The site was not able to open the valve to restore proper flow so the mill was shut down to make the necessary repairs.
What was the value to the customer?
Without adequate cooling for the lube oil, the bearings would not be properly cooled or lubricated for proper operation. This could result in abnormal bearing wear or damage leading to possible bearing failures. Proactive repair due to the monitoring notification allowed the customer to correct the issue, preventing undue maintenance and cost if the condition was allowed to continue for an extended period of time.
Mill bearing temps begin increasing on May 12th, then decrease to the model after restoring proper flow.