Inner Race Bearing Defect Detected with Ultrasound in a Pulp and Paper Mill Pump

Manufacturing paper is a water intensive process. To ensure production stays on track, water must be freely available throughout the facility. To ensure that it is, the water is transported using a system of pumps, motors, and pipes.

A dump chest, like the one in Figure 1, plays an integral role in the paper manufacturing process. It resides in the forming or press section of a paper machine.

If this pump fails, there will be no water available in this section of the plant to form and press paper. The result of this is a halt in production. Unplanned production stoppages lead to tens of thousands of dollars in lost revenue per hour.

At a pulp and paper mill in Canada, an ultrasound technician took readings on this critical asset using an SDT340. They analyzed the data using a UAS3 and the Bearing Toolbox.

The Bearing Toolbox indicated to the technician that the bearing (SKF – NU308) was suffering from an inner race defect.

The bearing was monitored closely and replaced at the mill’s next planned shutdown.