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 on leakage load for leather and brass ignition relay pistons.
| Identifier | ExFiles\Box 65\1\ scan0208 | |
| Date | 28th January 1928 | |
| Y8685 28.1.28. IGNITION RELAY PISTONS. Leakage load. Leather piston to LeC.2242 (with light piston ring). Piston failed to rise at 96 lbs. with 15 lbs/sq.in. oil pressure. xxx 121 1/2 " " 20 " " " " ------- Brass piston and rings to E.75672. Piston failed to rise at :- 102 1/2 lbs. with 15 lbs/sq.in. oil pressure. 131 1/2 " " 20 " " " " ------- Method of testing : Spring load replaced by dead load on top of piston. Motor switched up from dead slow to 700 r.p.m. as each increase of load was applied. Load increased by 20 lb. stages until piston failed to move when speed was increased. | ||