The standard methods for evaluating micropitting in gears (for example, using FZG test rigs) are based upon profile deviations from the involute caused by pitting, however this analysis method is applicable only once significant pitting has already taken place to cause gross profile changes, and is...
Micropitting damage is one of the failure modes commonly observed on case-hardened gears and is caused by cyclic stresses and plastic flow on the asperity scale (Ref. 1). The micropitting degrades progressively the geometries of the contact surfaces whic...
10 V O I C E S If you make hardened gears and have not seen any micropitting, then you haven’t looked closely enough. Micropitting is one of the modes of failure that has more recently become of concern to gear designers and manufac-turers. Micropitting in itself is not necessarily a ...
To limit mild wear, a SP antiwear additive combination based on phosphate and thiophosphate was included in all test lubricants at a concentration of 0.12 wt% P and 2.2 wt% S. These additives are commonly employed in axle oils at such a concentration to lubricate gears and bearings....
Central to this process was using an accepted andrepeatable assay technique for documenting the amount of micropitting without removing the gears. Thisassay technique utilizes graphite rubbed onto the surface and removed with clear tapes. Other techniqueswere also evaluated, but the graphite/ tape ...
PhosphateMicropitting, one form of fatigue damage, can lead to serious breakage if it progresses. In this study, I examined lubricants with different types of phosphate additives and considered their influence by analyzing the surfaces of gear teeth. The test results showed that while lubricants ...
Lubricants That Decrease Micropitting for Industrial GearsThe invention relates to an industrial gear formulation containing a high TBN overbased detergent that results in decreasing micropitting for industrial gears.WARD, William C.O'CONNOR, Brian M.VINCI, James N....
To close this module gap in the investigations, one gearset with module mn = 16 mm is used in the test runs. The geometry is designed to achieve similar sliding velocities along the path-of- contact.The profile shift of the regular C gears is designed for equal specific slid- ing...
Lubricants That Decrease Micropitting for Industrial GearsThe invention relates to an industrial gear formulation containing a high TBN overbased detergent that results in decreasing micropitting for industrial gears.William C. WardBrian M. O'Connor...
Gear simulation tests were performed in a Falex machine, using a roller–disc geometry, in order to evaluate the lubricant temperature and friction coefficient corresponding to each gear oil. Gear micropitting tests were performed on the FZG machine, using type C gears, and lubricant samples were...