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iglidur  | Technical data
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        Wear resistance


        The wear of components depends on many different      Wear and temperature
        factors, therefore it is difficult to make general statements   Within wide temperature ranges, the wear resistance of the
        about the wear behaviour. In many experiments and tests,   iglidur  plain bearings shows little change. In the maximum
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        the measurement of the wear is a primary factor. In testing,   temperature range, however, the temperature increases
        it has become clear what variances are possible between   and the wear of the plain bearing increases. One particular
        different material pairings. For given loads and surface   exception is represented by iglidur  X. The wear resistance
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        speeds, the wear resistance can easily vary by a factor of   of iglidur  X greatly increases as temperature increases and
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        10 between material pairings that run well together.  reaches the optimum wear resistance at a temperature of
                                                              +160°C. Then resistance decreases again, gradually.
        u Shaft materials, page 56
                                                              Wear during abrasive dirt accumulation
        Wear under load                                       Special wear problems frequently occur if abrasive dirt
        Different loads greatly influence the bearing wear. Among   particles get into the bearing. iglidur  plain bearings can
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        the iglidur  plain bearings, certain materials are optimised   clearly improve the operating time of machines and systems
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        for low loads, while others are suitable for use with high or   in these situations. The high wear resistance of the materials
        extremely high loads.                                 and the dry operation result in the highest service life. As
                                                              no oil or grease is on the bearing, dirt particles cannot
                                                              adhere or penetrate as easily into the bearing. Most debris
            100
                                                              simply falls away from the bearing thus limiting potential
                                                              damage. If however, a hard particle penetrates into the
             10                                               bearing area, then an iglidur  plain bearing can absorb this
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                                                              particle. The foreign body becomes embedded in the wall
          Wear [µm/km]  1                                     of the plain bearing. Up to a certain point, operation can         Picture 07: High wear resistance: plain bearing in   Picture 8: Wear experiments with aluminium shafts

                                                              be maintained at optimal levels even when there is extreme
            0.1
                0.25     0.75      1         2        5       dirt accumulation.                                                 permanent contact with sand
                                                              However, it is not just hard particles that can damage
                Load [MPa]                                    bearings and shafts. Soft dirt particles such as for example,
                    iglidur  G    iglidur  M250  iglidur  X
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                    iglidur  J    iglidur  W300               textile or paper fibres, are frequently the cause for increased
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        Diagram 11: Wear of iglidur  plain bearings under low   wear. In this instance, the dry operation capability and the
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        pressures, Cf53 shaft, v = 0.1m/s                     dust resistance of the iglidur  plain bearings go into action.
                                                              In the past, this helped save costs in many applications.
            100                                               Wear and surfaces
                                                              Shaft surfaces are important for the wear of bearing
                                                              systems. Similar to the considerations for the coefficient of
                                                              friction, a shaft can be too rough in regard to the bearing
             10                                               wear, but it can also be too smooth. A shaft that is too
          Wear [µm/km]                                        rough acts like a file and during movement separates small


                                                              particles from the bearing surface. For shafts that are too
              1
                5            10          20           45      smooth, however, higher wear can also occur. An extreme
                Load [MPa]                                    increase in friction results due to adhesion. The forces that
                    iglidur  G    iglidur  P    iglidur  Z    act on the mating surface can be so large that material
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                    iglidur  J    iglidur  V400  iglidur  Q
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                    iglidur  W300                             blow-outs occur.
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        Diagram 12: Wear of iglidur  plain bearings at medium   It is significant to note that wear by erosion is non-linear,
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        and high pressures, shaft: Cf53, v = 0.1m/s           random and cannot be accurately predicted.
                                                                                                                   ASEAN 09/2023  ASEAN 09/2023  Picture 9: Erosion damage due to shafts that are too smooth

        54     Online tools and more information u www.igus-asean.com/iglidur                                                               3D CAD files, prices and delivery times online u www.igus-asean.com/iglidur              55
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