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).
Comparative heat test of insulation specimens, detailing shrinkage and distortion.
| Identifier | ExFiles\Box 39\3\ Scan201 | |
| Date | 12th September 1922 | |
| EPC. PB.50. COPY Sept 12th 1922. COMPARATIVE HEAT TEST OF SPECIMENS OF INSULATION. For this test, circular mouldings of Elo, Bakelite and mouldensite were used, the actual test being carried out by Mr. Hall in the chemical laboratory. The three mouldings were immersed in molten wax at a temperature of 180°C for 144 hours, and again subjected to the same temperature, but in air, for 72 hours. Before and after the test the diameter of each was measured with the object of ascertaining what shrinkage took place. It was afterwards found, however, that the specimens under test had not only shrunk, but had become distorted there being a difference in the measurements of the diameter at various points round the periphery. In the results given below, the figures for the diameter of each specimen, obtained after the test, are the maximum and minimum of three measurements. Specimen. Dia. before Test. Dia. after Test. Percent. Shrinkage Max. Min. Max. Min. Elo. 1.851" 1.810" 1.808" 2.32 2.22 Bakelite. 1.860" 1.828" 1.818" 2.26 1.72 Mouldensite. 1.856" 1.832" 1.822" 1.83 1.29 In addition it was found that the Bakelite had slightly blistered, while the Elo and Mouldensite had only just commenced. | ||