WIB SA - Precision Redefined for a World in Motion

The radial clearance is not considered a quality criterion. An improper radial or axial clearance may have detrimental implications during operation within an application. This may include suboptimal noise levels, heat generation, rigidity, and fatigue life. Prior to recommending an internal clearance range, our applications will run an analytical simulation on the bearing and application to ensure optimal performance. For more complex system, our application engineers can complete a FEA analysis, particularly when evaluating multiple bearings within a non-rigid housing.

The 100 Cr6 steel rings manufactured by WIB are stabilized after hardening by annealing. As a result of this treatment, they can be used at temperatures of up to 150°C. They have a hardness of 60 to 64 HRC For applications operating at high temperatures or in order to reduce their sensitivity to shock loads, it is necessary to stabilize the rings at higher temperatures after hardening. It should be noted that such a stabilization will slightly reduce the hardness of the rings.

The resistance generated by the seal (if present), depending on the surface finish of the outside diameter of the inner ring, as well as of the rotational speed. The resistance generated by the cage, depending on the geometrical form and the machining quality of the cages. The resistance generated by the lubricant, depending on the lubricant viscosity and filling quantity as well as the rotational speed. At low speed and with fine instrument oil this resistance is insignificant. It will be higher at low temperatures and at high viscosity of the lubricant. Grease lubricated bearings will show, according to the grease type and filling, a much higher friction torque than oil lubricated bearings.

By applying surface treatments on outer ring contact surfaces, it is possible to improve certain mechanical characteristics such as the hardness. By doing this, we can increase wear resistance while decreasing the friction coefficient. With certain treatments it is possible to achieve high resistance to specific chemical agents. The table below shows a small sample of examples of such surface treatments and their resulting technical characteristics.

It is even possible to apply a coating on the outer ring, before assembling the bearing, thus guaranteeing the best possible geometrical forms. The machining of grooves ensures that the coating perfectly adheres to the metal surface. Additionally, a wider temperature range may be covered.

The noise level is an important quality criteria of a ball bearing. It mainly depends on the following factors: precision of the geometric forms surface finish of the raceway and the balls cleanliness of the bearing type of lubricant type of cage rotational speed

Packaging is a very important parameter for the retention of the bearing quality during transport and storage. It is designed to protect the bearings against corrosion, dust, and other pollutants. Apart from that, each unit is labeled and carries all the relevant information concerning the technical and quality features of the bearing. The production batch number is printed on the label and guarantees the traceability of the product, as well as the identification of the manufacturing date. Therefore, it is advisable to unpack the ball bearing only prior to use or assembly.