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).
Testing an ignition oil relay leather piston ring.
| Identifier | ExFiles\Box 72\1\ scan0019 | |
| Date | 21th April 1925 | |
| R.R. 493A (50B) (D.B. 175 25-9-24) J.H.D. EXPERIMENTAL REPORT. Expl. No. REF. Hs{Lord Ernest Hives - Chair}/GHR/LG21.4.25. IGNITION OIL RELAY LEATHER PISTON RING. Tests carried out on 8-EAC-11 unit. Chrome leather ring of wider section :- [TABLE 1] R.P.M. | Flywheel ° advance. | Control ° advance. | Main oil pressure. | Relay oil temp. | Bearings. Oil temp. 500 | 22 | 2 | 20 lbs/sq.in. | -- | -- 1000 | 29 | 6 | 22 | -- | -- 1500 | 38 | 13 | 22 | 51°C | -- 2000 | 48 | 19.5 | 22 | 57°C | -- Total running above normal relay oil temp. 60°C = 4 1/2 hrs. 3 1/2 hrs. being at an average of 90°C CURVE TAKEN AT FINISH. [TABLE 2] R.P.M. | Flywheel ° advance. | Control ° advance. | Main oil pressure. | Relay oil temp. | Bearings. Oil temp. 500 | 21 | 1 | 14 | 91°C | 58°C 1000 | 29 | 6 | 20 | 90°C | 58°C 1500 | 38 | 13 | 22 | 89°C | 57°C 2000 | 46 | 18.5 | 21.5 | 90°C | 58°C Leather piston ring O.K. at finish, no sign of buckling. Wider section decided improvement. Relay body insulated one side only for 1/2 hr. at 90°C, with no difference to leather ring. Hs{Lord Ernest Hives - Chair}/GHR. | ||