If rolling bearings are purchased solely on the basis of the unit price, the purchase of supposed bargains can ultimately be expensive. This is because the risk of procuring counterfeit bearings increases. Unfortunately, this risk is too often ignored - with the result that the machine manufacturer or its customer has to incur higher operating, repair and downtime costs. This additional cost is almost always greater than the savings in procurement.

The origin of counterfeits
Counterfeit bearings often come from low-wage countries. Inferior materials and outdated machines are used in their production. They are usually marked with counterfeit brand names and designations of origin, and the packaging also imitates the design of a brand manufacturer.

Basically, such bearings are of poorer quality than the originals - otherwise they could not be produced so cheaply. They may last long enough to pass pre-production tests, but they fail prematurely in the field. This can damage the reputation of both the machine and the bearing manufacturer and is one of the reasons why NSK is taking vigorous and active action against counterfeiting. In addition, manufacturers and distributors of counterfeit bearings are unlikely to offer technical support or advice when premature bearing failures occur.

It all depends on the material
The materials used in the production of counterfeit bearings are generally of inferior quality. This has consequences, as the quality of the bearing steel (often developed for a specific application profile) is a key factor in the reliability of the bearings. In NSK's experience, the difference in the service life of genuine and counterfeit bearings can be up to a factor of 20.

The fatigue life of alloyed bearing steels such as 100 Cr6 depends primarily on their purity. Oxidic or non-metallic inclusions in particular favor negative effects under the raceway surface. For example, aluminum oxide inclusions caused by oxidation during melting lead to a considerable reduction in bearing service life. This is because these inclusions are hard and can break open during machining processes such as forging. This causes them to shrink and weaken the structure.

In collaboration with a leading steel manufacturer, NSK has developed high-purity materials such as Z-steel, EP-steel and Bneqartet that prevent this effect. In addition, special melting processes are used in the production of NSK rolling bearings that reduce the non-metallic content in the steels used and thus extend the service life of the rolling bearings.

The heat treatment of the steel is another factor that explains the differences between genuine and counterfeit bearings. Materials such as the SHX steel used by NSK undergo a specific heat treatment that minimizes bearing wear, especially at high operating temperatures. This measure is not only effective when the bearings are used in hot plants and in process technology systems. The heat treatment of the steel also has a positive effect in machine tools where high spindle speeds lead to excessive heating of the drive.

Only purchase rolling bearings from reliable sources

NSK continues to make great efforts to identify counterfeits and prosecute their producers. Nevertheless, counterfeit bearings are repeatedly found in supposedly original packaging - even in Germany. For this reason, users of rolling bearings should always exercise caution when purchasing and only purchase NSK branded rolling bearings from trustworthy sources such as authorized NSK sales partners. as