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 report comparing loads and torque for cork and Ferobestos clutch discs under varying oil and wear conditions.
| Identifier | WestWitteringFiles\R\2October1927-November-1927\ 160 | |
| Date | 23th November 1927 guessed | |
| contd :- -2- The unit was wound up as when starting the engine. We give the following loads obtained in the tests :- Conditions. Load at lever.lbs. Torque at pinion. lbs.ins. Torque at engine shaft. lbs.ins. 3 corks in semi 10 100 850 oily condition. Corks very oily. 8 80 680 ------------------ ---------- ---------- ---------- Allowing for wear of .050" taking place of the corks which then reduces the clutch spring to 118 lbs., the following are the results :- Corks in semi 8 80 680 oily condition. Cork very oily. 5.5 55 467.5 ------------------ ---------- ---------- ---------- We tried Ferobestos discs under the same conditions the loads being :- Discs in semi 8 80 680 oily condition. Discs very oily. 6.5 65 552 Allowing for wear :- Discs in semi 5.5 55 467.5 oily condition. Discs very oily. 4.25 42.5 361.25 ------------------ ---------- ---------- ---------- As a result of these tests we found that Fero-bestos discs do not give the required amount of friction to be reliable. It will be noticed that when the corks wear .050" and are in an over-oily condition, slipping under heavy contd:- | ||