Vesconite bearings were successfully installed in vertical-spindle sump pumps operating in a paper manufacturing plant that handles dirty process water, demonstrating their suitability for demanding industrial pumping environments.
Three vertical sump pumps were fitted with Vesconite shaft support bearings to improve reliability and performance in abrasive, water-lubricated conditions. The pumps operated at 1,200 RPM, handling dirty water in 4 m (13.12 ft) vertical pump assemblies. Each pump featured a 75 mm (3 in) shaft, 110 mm (4 in) housing, and 250 mm (10 in) bearing length.
The Vesconite bearings were installed into a steel insert positioned between the flanges joining the column stages of each pump. Lubrication was provided by semi-clean process water fed directly into the bearing through the flange connection, enabling continuous water film support during operation.
To optimise performance, grooves were machined into the bearing surface to ensure consistent water flow across the bearing interface. This design supported effective heat dissipation and water lubrication, critical in vertical sump pump applications where solids and contamination could affect operating conditions.
Vesconite was selected for this application due to its wide availability in multiple sizes, competitive pricing, and its performance advantages over traditional bearing materials used in similar pump systems.
Operational results were positive. Two of the three pumps operated successfully for more than one year without any reported issues, confirming stable performance under continuous duty in dirty water conditions.
The third pump experienced bearing failure after the cooling water supply was inadvertently switched off. This interruption eliminated the cooling of the bearings, resulting in excessive operating temperatures and bearing overheating. Despite this, shaft damage was minimal, and the shaft was fully reusable after installation of new bearings.
Following the incident, new Vesconite bearings were installed with improved groove design to increase cooling water distribution across the bearing surface. The update reinforced an important design consideration in water-lubricated systems: groove number, size, and geometry needed to be carefully engineered to ensure sufficient flow and heat removal across the full bearing length.
Vesconite and Vesconite Hilube, in particular, are internally-lubricated bearing materials that tolerate short periods of cooling water interruption. Their low-friction characteristics allow them to withstand temporary dry-running conditions such as dry start-up, pump snoring (when a pump draws a mixture of both water and air because the water level has dropped below the pump’s optimal suction level), or brief loss of lubrication water, helping reduce the risk of catastrophic failure.
This installation, completed in the early 2000s, highlighted the value of combining engineered bearing materials with correct hydraulic design in extending pump life and improving reliability in paper mill operations.
