Calculation Method and Boundary Criteria for the Continuous Wear Behaviour of Grease Lubricated Gears with Regard to Different Material Combinations
Gear Research Centre (FZG)
The fact that wear is a significant and often life-limiting type of damage to slow-running gears, has been known for a long time and has been proven by systematic investigations for both oil and grease lubrication. However, recent researchshows that grease-lubricated gears can be increasingly at risk from wear even under higher operating conditions that are supposedly not critical to wear. Essentially, the wear behaviour of grease-lubricated gear wheel pairs is determined by the lubrication mechanism that is set up (circulation/release). Of particular interest here is the boundary area between the two lubrication mechanisms, which has not yet been systematically investigated. This gap in knowledge is to be closed and corresponding calculation possibilities for the wear behaviour of grease-lubricated gears are to be examined, also taking into account different material pairings.
Systematic experimental investigations are to be carried out to examine the transition area of the lubrication mechanism from circulation to release trench more closely and to determine suitable limit criteria. From the knowledge gained from these investigations, a computational approach for estimating the lubrication mechanism is to be derived, if possible. In addition, different material pairings will be considered and possibilities for converting the wear behaviour of the case-hardened/case hardened pairing to the case-hardened/tempered pairing (and vice versa) will be examined. Based on the results, suitable wear categories for the low-speed wear test for lubricating greases (DGMK 725) are to be determined by means of suitable tests.
DGMK Research Report 796 was published in February 2021.
The results of the project were summarised in a brief abstract .
Dr. Jochen Blume
Klüber Lubrication Munich SE & Co.KG
IGF - Industrial Collective Research
Federal Ministry for Economic Affairs and Energy (BMWi)