Pump cavitation caught three weeks early

Background

A municipal water facility relies on a pump whose internal condition is difficult to judge while it runs. Cavitation can damage the impeller progressively. Our monitoring looks for a change in the pump’s vibration signature while there is still time for maintenance to investigate and arrange the work.

The problem

An audible fault comes late in the deterioration described here. By the time someone can hear the problem on the floor, damage has occurred and the repair can force an unplanned outage. The team needs an earlier indication tied to the pump itself, with a record showing how its behaviour is changing.

How we found it

We use a vibration sensor at the pump bearing housing and a temperature probe on the housing. Trend-based alerts draw attention to changes in the readings. Following the vibration signature over time makes the developing problem visible ahead of the point at which it would become audible to the team.

What changed

Maintenance has warning in advance of audible failure and can schedule the repair. The operating history gives the team a reason to inspect the pump and a basis for arranging the work. The change is in the timing of that decision, with the developing signature available while the pump is still running.

The lesson

We follow the direction of the readings as well as the latest value. For this pump, the change begins before a person would hear it, which makes the trend useful for planning. Keeping the vibration and temperature history available gives maintenance a way to review the developing condition, record the repair point and watch the pump’s behaviour when it returns to operation.