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).
Required nickel content for Phantom push rods based on a coefficient of expansion graph.
| Identifier | ExFiles\Box 27\4\ Scan134 | |
| Date | 22th May 1928 | |
| To ROY.{Sir Henry Royce} From Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} K3035 Hs{Lord Ernest Hives - Chair}/RmL/LG22.5.28. PHANTOM PUSH RODS. +7060 Co-efficient of expansion. % NICKEL. Invar We require some steel tube for the Phantom push rods having a co-efficient of expansion of about .000018. As will be seen from the attached curve this should be obtainable with a nickel content of either just over or just under 20%. The section of the rod will be the same as the present steel rod. Will you please let us know if tubes such as we require are obtainable. This matter is urgent. If not exactly, what is commercially obtainable. Hs{Lord Ernest Hives - Chair}/R.M. | ||