Improved Oil-Off Survivability of Tapered Roller Bearings.
Abstract
This development program was to improve the oil off survivability of a tapered roller bearing when applied to a helicopter transmission, since the tapered bearing has shown a performance advantage in this application. However, the critical roller end rib conjunction is vulnerable to damage in an oil off condition. Through an initial screening, three powdered metal materials were selected to use a rib material for oil off evaluation. These were: M2 steel to a 65% density, CBS 1000M 65% density, CBS 1000M 75% density. The bearing styles tested were both ribbed cone (inner race) and ribbed cup (outer race). Carburized solid CBS 600 was also used as a ribbed material for comparsion of oil off results. The tests were conducted at six speed from 4000 rpm (0.26 million DN) through 37000 rpm (2.4 million DN). The ribbed cup style bearing achieved longer lives than the ribbed cone style. A standard bearing lasted only 10 minutes at 4000 rmp; however, the 30 minute oil off goal was achieved through 11000 rpm using the survivable ribbed cup bearing.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1987
- Accession Number
- ADA189359
Entities
People
- G. E. Kreider
- P. W. Lee