Dimensional expansion of two Nitro Alloy bushes after final heat treatment.
| Identifier | ExFiles\Box 154a\1\ scan0162 | |
| Date | 19th June 1929 | |
| 44469 To H.L. from Hs {Lord Ernest Hives - Chair} /Rm. {William Robotham - Chief Engineer} Hs {Lord Ernest Hives - Chair} /Rm {William Robotham - Chief Engineer} 4/LG19.6.29. NITRO ALLOY. 2 bushes : We find that final heat treatment has expanded the above bushes .0045" externally and .0035" internally. The length has also increased by .004" to .005". [Diagram showing a cross-section of a bush with measurements before and after heat treatment (H.T.)] External Length: 1.500 BEFORE H.T. 1.5045 AFTER External Diameter: 1.000" BEFORE DIA. 1.0045" AFTER Internal Diameter: .875 DIA BEFORE .8785 AFTER Bushes taper down from each end to point A-A. {Mr Adams} -.001". At A-A, B-B or C-C, they are .0004 out of round. Highest and lowest dia. EX. .00125. " " " " In. .001". Hs {Lord Ernest Hives - Chair} /Rm. {William Robotham - Chief Engineer} | ||
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).