Heavy-duty bearing system

SKF have launched a new range of spherical plain bearings with heavy-duty seals. Called the SKF Heavy-Duty System, the bearings have been designed with no weak links. The steel-on-steel construction with newly developed seal technology and high-performance lubricants allows the components of the bearing to complement each other. Costs are reduced through longer maintenance intervals.

Two key developments of the system are the geometry of specially machined grooves on the bearing face and the development of the LS steel-reinforced seal. The multi-groove system used on the bearing allows more grease to be retained in the bearing, while at the same time providing improved lubricant distribution. The grease remains fresh for longer and relubrication can be carried out under full load. The multi-groove system is standard on all bearings of 150mm diameter and above, but smaller sizes can also be supplied in this configuration to solve difficult lubrication issues.

The retention force of the LS seal has been increased threefold due to the incorporation of a steel insert. This means the seal is not ejected during bearing lubrication and the critical sealing lip cannot be damaged mechanically or by heavy contamination. The seal has three lips, providing dimensional stability and optimum stiffness. The seals are made from oil- and wear-resistant nitrile rubber and are suitable for operating temperatures from –25ºC to +120ºC.

There are two different greases within the heavy-duty system. LGGB2 is a new biodegradable ‘green grease’ for use where service life is satisfactory but where environmental pollution is a concern. LGHB2 is a high-performance grease which offers superior mechanical stability combined with anti-oxidation and anti-corrosion properties.

The system covers a range of sealed spherical plain bearings with 47–180mm outside diameters and 25–120mm internal diameters.