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).
Hardness test results for a 20 HP valve from chassis 89-K6.
| Identifier | ExFiles\Box 48\4\ Scan137 | |
| Date | 17th July 1924 | |
| By.{R.W. Bailey - Chief Engineer} c. to Hs.{Lord Ernest Hives - Chair} c. to Wor.{Arthur Wormald - General Works Manager} X4226 H111/EF7824. Laboratory. Re 20 HP. Valve from Chassis 89-K6, submitted for hardness tests. As requested in your memo. By17/H.17.7.24, we have cut a section from the above valve and have tested same on the Rockwell machine in the manner described in our previous report. The results are shown on the attached chart. It will be noted that only a very small sectional area has hardened to a figure above the specification maximum limit (viz. 277 Brinell). We should like to know what percentage of valves fail in this way, as we have no information on this point. H1. He | ||