This CCGT Power Station was looking to improve its approach to plant utilisation, cost reduction and risk reduction, and installed MBVI condition monitoring units on around 40 plant items, including:
- Main Generator
- Boiler Feedwater pumps
- Condensate Extract pumps
- Turbine Shell Exhaust Frame blowers
- Main Bearing lube oil pumps
- Instrument Air compressors
- Load compartment ventilation fans
- Cooling Air Fan diffuser areas
- Gas compartment ventilation fans
- Hydraulic fluid pumps
- Liquid fuel vent fans
- Gland exhaust blowers
- HPU Heating and Cooling circulation pumps
- Turning Gear Motor
- Exhaust bearing area blowers
- Feedwater pump auxiliary oil pumps
- Auxiliary boiler deaerator pumps
- LP Feedwater recirculation pumps
- Duct burner cooling air fans
- Duct burner augmenting air fan
- Vac Flash Tank drain pumps
Regular monthly reports were provided, monitoring the outputs and diagnosing problems as signals changed.
After a significant period of time, the turning gear motor was showing signs indicating elevated temperature, and then gradually indicating a developing bearing problem. This was stripped down at a convenient time when the plant was shut down and a faulty bearing identified. The comment from the client was that if it had not been detected at that time it would have gone on to complete failure.
During the period 2016 – 2017, a gradually developing signal at 1x rotational speed was detected on the Augmenting Air Fan. The MBVI unit correctly identified a developing problem, that if left untreated could have led to catastrophic failure of the Non-Drive End bearing on the motor. This problem was not detected by conventional vibration monitoring. The underlying cause appears to have been corrosion of the motor shaft, leading to progressive cocking of the bearing through the process of oxide jacking. Had the motor failed in service, it could have led to shutdown of the power station operations for several days whilst the motor was removed, overhauled and replaced, incurring a significant loss of revenue. Note that the MBVI system was able to detect this trend developing from about 18 months before it reached alarm levels, as shown in the diagram below:
What to do next
If you are interested in applying Faraday Predictive condition monitoring systems to your plant, give us a call on 0333 772 0748, or email us on info@faradaypredictive.com.
If you want to develop your business case for investment in Faraday Predictive condition monitoring systems, take a look at this.
And if you want to know more about our condition monitoring systems themselves, click here.