The WITTE friction bearing design

Friction bearing technology

Bearings are one of the core components for gear pumps. The material and design must be carefully selected and coordinated with each other to ensure safe and efficient operation of the pump.

Normally friction bearings are used in gear pumps. With this bearing type, the internal diameter is somewhat larger than the journals stored inside it. The transported medium penetrates into this small area through lubrication grooves through which a hydro-dynamic lubrication film is established from the medium in the bearing. The shaft “floats” in the bearing. For friction bearings lubricated with media, it must be ensured that the lubricating film does not tear. Otherwise the shaft can no longer be lubricated and it results in damage to shafts and bearings. This damage is normally irreparable and results in bearings and shafts having to be replaced.

Friction bearing

WITTE has a wide portfolio of different bearing designs and materials.
Many materials can be made even more resistant through additional coating. Friction bearings are used in gear pumps. Depending on the needs and applications, it may make sense to use other technologies.

Collar bearings

Collar bearings are used with higher pressures on the suction side with shafts coming out on both sides. During start-up, the pressure may have an effect on the friction bearing through the casing balancing hole from the back to prevent a possible braking effect on the gears. The bearing is supported in the casing recess through the collar and cannot be pressed on to the gears. Collar bearings are also used if they are larger pumps.

Roller bearing

A sealed roller bearing is used for complex requirements. Roller bearings can either be used as hybrid bearings (metal + ceramic) with lubrication or as a sealed bearing unit with shaft protection sleeves, for example, for rubber solutions (medium viscosity ~15Pas), which is flushed with thin solvents.