Good China Manufacturer Standard And Custom Slewing Bearing

Anti-corrosion and wear-resistant coating on sealing contact surface for slewing bearing

For large-scale high-end slewing bearings, due to special working conditions, such as working in muddy water, river water or sea water, special treatment is required for the sealing contact surface.

As a rubber seal contact, typically softness overcomes rigidity, and the sealing contact surface is often worn into grooves, so that the sealing effect is large. discounted, thereby losing the sealing function.

Surfacing stainless steel, with the help of stainless steel’s characteristics of non-corrosion, high strength, high hardness and good wear resistance, when combined with the slewing bearing, the welding performance is poor, and the grinding effect is unsatisfactory.

Brass surfacing, as the metal properties of brass, confirm that the hardness is moderate, the surfacing welding is easy to combine, and it is easy to accept as a traditional solution, when compared with sprayed ceramics, and so on.

Spraying ceramic process (chromium trioxide), high strength, high bonding performance, best surface roughness grinding, because of the particularity of ceramics, contact with rubber seals, almost no loss of precision, the best effect in experiment and practical .

NoWear coated slewing bearings

NoWear is a wear-resistant carbon coating that can be applied to the rolling elements and inner ring raceway(s) of a bearing (designation suffix L7DA) or only the rolling elements (designation suffix L5DA) (fig. 1).

A physical vapour deposition process applies the wear-resistant carbon coating. Thickness of the coating ranges from 1 to 3 μm, depending on the size of the bearing. The hardness of the coating is 1 200 HV10.

NoWear coated bearing surfaces retain the toughness of the underlying material while adopting the hardness, improved friction properties and wear-resistance of the coating.

During the running-in period, minute amounts of the coating material are transferred to the counter-surfaces. This coating reduces friction and improves resistance against wear and smearing, even in bearings where only the rolling elements are coated.

Functional impairment due to base metal corrosion for slewing bearing

Base metal corrosion (red rust formation) is the most common type of corrosion on steel materials and is caused by the simultaneous presence of moisture and oxygen. In the metalworking industry, rust formation primarily impairs the component function and operating life.
As a general rule, minor corrosion to the exterior of a fitted bearing does not have an adverse effect. Rust formation in the interior of the bearing is, however, critical in many respects.

Localised pitting corrosion on rolling surfaces generates stress peaks during overrolling, which can lead to premature fatigue. As in the case of false brinelling, rust particles have an abrasive effect and lead to wear. Lubricants and seals serve to protect the internal components of a bearing.

The applied protective coatings act as surface protection in the outer area of a bearing and thus prevent damage to the rotary shaft seals.

Innovative coating variants as key technology for slewing bearing

With its innovative coating variants, Schaeffler ensures that premature fatigue does not occur, thus enabling long-term function.By optimising process parameters and making further developments in plant technology, Schaeffler is providing an important and futureoriented key technology for the deposition of thin and uniformly distributed coatings.

In the area of corrosion protection, the protective coatings produced in this way bring about an improvement in general component characteristics and play a key role in optimising components.

The outstanding characteristics of the original thin film coating(electroplated zinc alloy system) have been continuously improved by the further development of this system and the establishment of new coating systems, and correspond to (or significantly exceed) the current level of technology.

As a globally established system supplier of automotive and industrial components,Schaeffler equips its products with added value through state-of-the-art technologies based on high-performance surface treatments.