From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Test results and details for Ferobestos self-aligning gearbox bushes.
| Identifier | ExFiles\Box 136\2\ scan0324 | |
| Date | 7th May 1941 | |
| To Ev{Ivan Evernden - coachwork}/Tln. From Hm{Capt. W. Hallam - Head Repairs}/GB. Copy to Hm.{Capt. W. Hallam - Head Repairs} Ev.{Ivan Evernden - coachwork} Hm{Capt. W. Hallam - Head Repairs}/RJH. Ev{Ivan Evernden - coachwork}/JD.{J. Draper - Frames} FEROBESTOS BUSHES. Here are some details of Ferobestos bushes. These are in reply to your query concerning a self aligning bush for a gear box operating application. Ferobestos is made either unimpregnated (L.A.) or oil impregnated (N.W.I.). When used without lubrication, the unimpregnated Ferobestos has the lower coefficient of friction. Both types of Ferobestos have rather a high coefficient of friction when used without lubrication. When the bearing length is 1.5 x bore P x D x N should not exceed 3160 where P is bearing load in lb/sq.in. of projected area D = bore in inches N = R.P.M. Here are some test results. In all cases, the above formula was used to obtain bearing load, etc.. 1. FEROBESTOS L.A. - D = 1 3/8" N = 720 no lubrication µ was .29 at beginning of test and .39" after 170 hours running. 2. FEROBESTOS L.A. - D = 1 3/8" bush surface graphited. When N was 187 µ was .29 " N " 63.5 µ " .31 3. FEROBESTOS L.A. - D = 1 3/8" no lubrication When N was 720 µ was .25 " N " 187 µ " .26 This test was stopped after 40 hours because of squeal. 4. FEROBESTOS N.W.I. - D = 1 3/8" no lubrication. µ was .425 After 170 hours running, shaft wear was unmeasurable and bush wear was .005". 5. FEROBESTOS L.A. - D = 1 3/8" oil lubrication. When N was 720 µ was .015 " N " 187 µ 2 .004 | ||