Tribological research on the development of White Etching Cracks (WECs)

Pape, Florian; Terwey, Jan Torben; Wiesker, Sebastian; Averbeck, S.; Muhmann, Christian; Lipinsky, D.; Arlinghaus, Heinrich F.; Kerscher, Eberhard; Sauer, Bernd; Poll, Gerhard

doi:10.1007/s10010-018-0289-6

Cited by 11 publications

(19 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…WEC-associated time to failures become less critical at lower temperatures: in this study at 70 ℃ instead of 90 ℃ (Table 2), and in study of Pape et al. 25 at 80 ℃ instead of 100 ℃…”

Section: Discussionmentioning

confidence: 44%

“…In this study, WECs form only with oil A/A1 and not B/B1 . WEC-associated time to failures become less critical at lower temperatures: in this study at 70 C instead of 90 C (Table 2), and in study of Pape et al 25 at 80 C instead of 100 C . In this study, WECs are only been observed in REs, which present three times lower e a than washers (in which no WECs have been observed even in tests with 19 rollers and with RE sets renewed five times every 24 h) .…”

Section: Friction Energy Accumulationmentioning

confidence: 43%

“…The results question the proposed criteria and its correlation with time to failure because it does not take into account the following points: In this study, WECs form only with oil A/A1 and not B/B1 WEC-associated time to failures become less critical at lower temperatures: in this study at 70 ℃ instead of 90 ℃ (Table 2), and in study of Pape et al. 25 at 80 ℃ instead of 100 ℃ In this study, WECs are only been observed in REs, which present three times lower e a than washers (in which no WECs have been observed even in tests with 19 rollers and with RE sets renewed five times every 24 h) Pape et al., 25 WEC have also been found on the positive SRR area of the washers.

Figure 12.Approximate friction energy accumulation e a calculated across the contact width in the SKF LAD-100 81212 test with nine rollers. Calculations are as proposed by Kruhöffer and Loos 21 but with assumptions regarding the “asperity contact pressures.” …”

Section: Discussionmentioning

confidence: 65%

“…Oils A/A1 and B/B1 present the same ZnDDP and Calcium Sulfonate concentration, so that the formation of WECs cannot be explained solely considering the concentration of these two types of additives, sometimes pointed out as problematic. 20,22,23,25,26,39 More than additive themselves, more needs to be done to understand which type of tribochemical reactions could lead to material weakening and subsequent early bearing damage when lubricated with oil A but not with oil B. Oil B does have three additives extra and several hypotheses can be formulated as to why the tribochemical reactions could differ: the added friction modifier can lead to more uniform tribolayers reducing the fresh surface availability for a detrimental reactions; the polysulfide and sodium sulfonate additives can inhibit tribochemical reactions that would create detrimental byproducts; the more uniform tribolayers can act as a barrier to the detrimental byproducts that would weaken the bearing steel; etc.…”

Section: Discussionmentioning

confidence: 99%

“…These hypotheses are mainly based on tests of 81212 bearings on FE-8 rigs with a ''WEC-critical'' oil. [15][16][17][18][19] Based on this, it is suggested that WECs develop due to high frictional energy accumulation, 20,21 promoted by specific additives, [22][23][24][25][26] which lead to hydrogen ingress and subsequent weakening of the material. 4,19,23,[27][28][29][30] Lubricant additives, specifically extreme pressure and anti-wear (EP/AW) additives, are used to prevent from surface deterioration in mixed lubrication, notably to compensate lower and lower base oil viscosities.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

The influence of lubricant formulation on early thrust and radial bearing damage associated with white etching cracks

Ruellan

Stadler

Rydel³

et al. 2020

Proceedings of the Institution of Mechanical Engineers, Part J:

View full text Add to dashboard Cite

In the past, results have shown the influence of oil-additive systems in the life of rolling bearings, also hypotheses have been formulated on the influence of lubricant formulation on the development of early bearing damage associated with white etching cracks. In some earlier work of the authors with different operating conditions, early damage, and white etching cracks had been generated by mechanical stresses. In this study, tests with custom-made lubricants have been performed on thrust as well as radial bearings to clarify some assumptions. The tested oils differ only by the presence of three additives, but only one oil has led systematically to white etching cracks despite the fact that both oils lead to similar mechanical stresses. The results confirm that under mixed lubrication conditions with certain lubricant formulations, early damage, in particular white etching cracks, can be influenced by the oil-additive system likely affecting the bearing steel. Hypotheses are formulated and the influence of different parameters is discussed. This paper, combined with earlier work of the authors, confirms that the understanding and solution to an early bearing damage associated with white etching cracks can only be validated using the appropriate test method.

show abstract

Section: Discussionmentioning

confidence: 44%

Section: Friction Energy Accumulationmentioning

confidence: 43%

Section: Discussionmentioning

confidence: 65%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

The influence of lubricant formulation on early thrust and radial bearing damage associated with white etching cracks

Ruellan

Stadler

Rydel³

et al. 2020

Proceedings of the Institution of Mechanical Engineers, Part J:

View full text Add to dashboard Cite

show abstract

Fleetwide data-enabled reliability improvement of wind turbines

Verstraeten

Nowé

Keller

et al. 2019

Renewable and Sustainable Energy Reviews

View full text Add to dashboard Cite

Wind farms are an indispensable driver toward renewable and nonpolluting energy resources. However, as ideal sites are limited, placement in remote and challenging locations results in higher logistics costs and lower average wind speeds. Therefore, it is critical to increase the reliability of the turbines to reduce maintenance costs. Robust implementation requires a thorough understanding of the loads subject to the turbine's control. Yet, such dynamically changing multidimensional loads are uncommon with other machinery, and generally underresearched. Therefore, a multitiered approach is proposed to investigate the load spectrum occurring in wind farms. Our approach relies on both fundamental research using controllable test rigs, as well as analyses of real-world loading conditions in high-frequency supervisory control and data acquisition data. A method is introduced to detect operational zones in wind farm data and link them with load distributions. Additionally, while focused research further investigates the load spectrum, a method is proposed that continuously optimizes the farm's control protocols without the need to fully understand the loads that occur. A case of gearbox failure is investigated based on a vast body of past experiments and suspect

show abstract