PSI - Issue 57

Dr.-Ing. D. Jbily et al. / Procedia Structural Integrity 57 (2024) 199–216 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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gears having the same design as the actual gear pair. In this case, the gear manufacturing, gear accuracy, operating conditions, lubricant and operating temperature shall be appropriate for the actual gear pair. The cost required for this method is in general only justifiable for the development of new products as well as for gear pairs where failure would have serious consequences. • The Method B describes a procedure to derive the value of λ GFP from the result of any standardized test method applicable to evaluate the micropitting load capacity of lubricants or materials by means of defined test gears operated under specified test conditions. For this value, the differences between test and application should be taken into account. In the following, the calculation of micropitting is based on Method A to determine the local specific lubricant film thickness and on Method B to determine the permissible specific lubricant film thickness. These calculations are performed using the KISSsoft 2022 software package. The specific sliding (Fig. 14), which is the ratio of the sliding speed to the speed of a transverse profile in the direction of the velocity tangent to the profile (ISO 21771-1), at the root diameter of the pinion teeth is high (value of 3.75). The distribution of specific sliding along the path of contact is shown in Fig. 15.

Fig. 14. Specific sliding along tooth profile

Area of high sliding

Fig. 15. Values of specific sliding along the path of contact