Vibration measurement: rapidly increasing bearing damage

The condensate pump of a turbine showed bearing damage during a route measurement.

This case emphasizes the importance of extra attention as soon as limited damage starts

to show.

Observation during route measurement:

We can see a sudden increase in bearing fault frequencies. The measured damage is still in an early

stage. In the short term no actions need to be taken.

Advice:

The pump will be monitored further in two weeks’ time.

Observation during follow-up measurement (2 weeks):

2 weeks ago, during route B vibration measurements, we noticed early bearing damage in the pump.

We suggested to monitor the motor-pump combination.

The graph shows a strong increase of the vibration level after a short period of time. There is a strong evolution in the vibration level with fault frequencies on the inner ring.

Advice:

In view of the strong increase of the bearing damage in a relatively short period of time, it is advisable to overhaul the pump.

Damage analysis:

The pump was immediately overhauled. The following pictures show the damage.

Conclusion:

This case teaches us the importance of close monitoring of damage. Monitoring the machine enables us to get a clearer picture of the evolution. The follow-up measurement made sure that the machine could be switched with the B machine (redundant operation).

This way production loss (outage of the turbine) and the resulting high costs were avoided.