iglidur® - Wear resistance

Figure 1.13: Wear of iglidur® bearings at low loads, shaft: Cf53, v = 0.1 m/s

Figure 1.14: Wear of iglidur® bearings at medium and high loads, shaft: Cf53, v = 0.1 m/s

Picture 1.14: Test stand for extremely high loads up to 150 MPa and temperatures up to 250° C, pivoting

Wear resistance

As the wear of machine parts is dependent on various influences, it is difficult to make general statements about wear behavior. In numerous experiments therefore the wear as measuring quantity is significant. Here it becomes evident which varieties among the various material pairings are possible. With specified loads and surface speeds, the wear resistance can still vary slightly between popular material pairings by the factor 10.

Wear under load

Varying loads naturally influence the bearing wear very strongly. There are specialists among the iglidur® bearings for low, high or extreme loads. With hardened, smoothed shafts, iglidur® J can be designated as the most wear-resistant bearing material for low loads. iglidur® Q is on the other hand the specialist for extreme loads.

Wear and temperature

Within other temperature ranges, the wear resistance of the iglidur® bearings alters only little. The influence of temperature increases in the upper temperature range, and the bearing wear increases disproportionately high. The Table 1.8 compares the so-called wear limits. Here the iglidur® X represents a rare exception. The wear resistance of bearings made of iglidur® X for a start increases very strongly and reaches the optimum at a temperature of 160° C. After this it decreases again only slightly at first.

Wear with abrasive dirt accumulation

Special wear problems frequently crop up if abrasive dirt particles reach the bearings. iglidur® bearings can in such cases definitely enhance the operating time of machines and plants. The high wear resistance of the materials and the dry operation provide the maximum holding times. As there is no oil or fat at the bearing location, the dirt particles cannot easily penetrate into the bearing. The largest particle does not stick but simply fall away and cannot cause any more damage. In case a hard particle still manage to get into the bearing location, an iglidur® bearing can tolerate this particle. The foreign body is embedded in the wall of the bearing. Thus even under extreme dirt accumulations it can function up to a certain degree.
But it is not only the hard particles that damage bearings and shafts. It has been observed that soft dirt particles, for instance textile or paper fibers, can also frequently cause enhanced wear. Here too the dry operation and abrasion resistance of the iglidur® bearing have an effect and could in the past assist in saving costs in numerous applications

Wear and surfaces

Shaft surfaces are important for the wear of bearing systems. Like in the friction coefficient considerations, a shaft in terms of bearing wear can be too coarse or too smooth. A very coarse shaft acts like a file and detach small parts from the bearing's surface. Very smooth shafts also cause a high wear. The adhesion causes an extreme increase in friction. The forces acting on the gliding partner's surfaces can be so great that regular material damages take place.
The important thing here is the wear through erosion is not linear, but subject to chance and unpredictable.

Picture 09: High wear resistance: Bearing in permanent contact with sand

Picture 10: Wear tests with aluminum shafts

Picture 11: Erosion damages through excessively smooth shafts