Our service engineer spotted abnormal axial movement of Lean Solvent Circulation Pump’s Thrust Position after the machine started up. Axial displacement probe indicated the rotor travel 0.229 mm toward the active thrust bearing, which already exceeds its specification at 0.127 – 0.178 mm. Thrust bearing temperature was also slightly increased by 1 degree C correspondingly.

The alert and recommendation are issued to inspect the thrust bearing and adjust rotor endplay. This can prevent the rotor from running with excessive axial movement and ensure the pump can operate at the rotor center, which provides maximum performance.

Benefit Case:

Avoid downtime in case excessive rotor movement leads to rotor seizure. Pump overhaul duration can go up to 10-15 days.

Reduce maintenance cost from thrust bearing replacement and/or pump overhaul, which can cost 15,000-500,000 USD.

Customer investigated the thrust bearing and found minor damage on the pivot shoe of the thrust pads, which was confirmed to be within acceptable range. After re-adjusting rotor endplay, the pump operating condition returned to normal.