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).
Sending 8 cast bars of two different casting alloys (53 and R.R. 50) to the laboratory.
| Identifier | ExFiles\Box 170\2\ img127 | |
| Date | 13th February 1932 | |
| To Hs.{Lord Ernest Hives - Chair} HLL/AG.13.2.32. Laboratory. We send you herewith 8 bars cast in the standard Air Ministry chill (9" long and 1" diameter.) They represent two casting alloys. The high temperature alloy (such as is used for air cooled cylinder heads) is stamped 53. Two of these have been heat-treated (stamped 53H) and two are as cast (stamped 53). The other four are taken from production test pieces in our R.R. 50 alloy. This alloy is used for all castings such as water cooled cylinders and cylinder heads, crankcases, and general production. The 53 is used for pistons and other high temperature work. Hl. /He. | ||