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).
The effects of heat on micanite and Vulcasbestos insulation materials within a switch.
| Identifier | ExFiles\Box 24\2\ Scan023 | |
| Date | 8th June 1920 guessed | |
| Contd. -2- While hot the nuts remained tight due to the greater relative expansion of the aluminium base. As would be expected from its construction and composition the micanite was the most affected by the heating at this temperature range (80 - 100°C. The Vulcasbestos was hardly affected it only being possible to tighten the nut on the moveable contact pillar bolt by barely 1/4th turn. At this end of the switch there is only the Vulcasbestos insulation. There are quite a number of sheet insulations of a compressed fibre nature, with quite low shrinkage co-efficient at the range of temperature likely to occur, and it is considered that these (or pure mica) should be substituted for the micanite. It is not thought necessary to replace the vulcasbestos by mica. (Main switch no 160 here-with. L.F. was ready to carry out the test on this switch assigned to him, and I have done the heating test first). ___________ R.C.S. Jamie. R.R. 255 T.SEC. G.189 318(L) 100 SHTS. 6.26/10 | ||