A United States company were manufacturing a sea water pump to be used for an off shore oil rig in Asia.
Pump capacity 150 000 l/min
Pump speed 500 RPM
Approximate bearing load 3 kg/cm²
Pumped medium Sea water
VescoPlastics were approached to help with this vertical spindle pump application. This pump required a 30 sec
dry start up once per week.
Metal backed rubber bearings were originally specified. Rubber is an acceptable bearing material as long as there
is a suitable water lubrication cooling film available on the bearing. Rubber bearings do not survive when water
flow through the bearing is not present. For this reason Vesconite Hilube was considered.
Bearing sizes 155 x 127 – 250 mm long and 155 x 127 – 196 mm long (6" x 5" - 9.8" long and 6" x 5" - 7.7" long)
12 longitudinal grooves were added to each bearing.
The Vesconite Hilube bearings were Stainless Steel 316L backed.
The in-line shaft bearings were lubricated by the process sea water. Since it was not possible to prime the pump
on startup, the pump was required to run for 30 seconds without any lubrication on the bearings.
Tests conducted on the bearings were successful and Vesconite Hilube was included in the final design.
Due to the structural strength of Vesconite and Vesconite Hilube the metal backings required for rubber bearings
can be eliminated. This means a much more cost effective bearing.
The installation of a Vesconite bearing is done easily by press fitting or by freeze fitting. Cooling the bearing
down in a deep freeze or with dry ice will allow the bearing to be easily slid into place.