Schaeffler supplies its largest-ever spherical plain bearing
10 Sep 2019
Schaeffler has produced the largest spherical plain bearing in the company’s history – a monster weighing in at around 4.7 tonnes.
The Godzilla of the bearings world boasts an outside diameter of 1,900mm, a bore diameter of 1,500mm, and a height of 600mm.
It will be used on a cutter suction dredger designed and built by Royal IHC, a Dutch company that specialises in equipment, vessels and services for the offshore, dredging and wet mining markets.
Cutter suction dredgers remove solid material from water beds, with a vacuum used to lift stones and transport them to shore using floating pipelines.
Particular strain is placed here on the connection between the pipeline and the ship, which is relies on a spherical plain bearing mounted on the hull that supports the rotary motion that takes place between the hull and the pipeline.
The bearing’s size was not its only record for Schaeffler; the company created the colossal producearing according to the customer’s requirements in just three months.
The shock loads that occur in the application meant that the inner and outer rings had to be implemented in a single-piece design.
"To ensure a long operating life and low levels of wear, Schaeffler created a special system of lubrication grooves, which are designed in such a way that the grease is evenly distributed, even during small swivelling movements of around 20 degrees, thus ensuring optimum lubrication," said a spokesperson.
Because the operating conditions found in offshore applications also require special protection against corrosion, the sliding surfaces of the bearing were coated with a proven lubricating varnish, which ensures that no metallic contact occurs between the inner and outer rings, even in the event of insufficient lubrication.