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).
Analysis and testing report on sylphon tubes for thermostats.
| Identifier | ExFiles\Box 180\M2\M2.3\ img011 | |
| Date | 24th March 1920 | |
| To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. c. to BN.{W.O. Bentley / Mr Barrington} c. to L. c. to D.{John DeLooze - Company Secretary} ORIGINAL index MAR 24 1920 Hs{Lord Ernest Hives - Chair}2/LG23.3.20. RECEIVED X.3902 SYLPHON TUBES FOR THERMOSTAT CONTROL Acting on your suggestion, we have taken the sealing plug out of one of the sylphon tubes. As soon as the seal was broken, air entered the sylphon tube until it had extended in length .350". As this is the maximum lift allowed on the valve, it means that when the valve is fully open, there is atmospheric pressure inside the sylphon tube. It also means that if the sylphon tube failed the valve would go on to the full open position and no harm would result. The liquid which was contained in the tube was analysed by Mr. Hall and found to contain 65% alcohol and 35% water or approximately two-thirds alcohol and one-third water. The amount of liquid which was in the sylphon tube was 7.55 cu. centi-metres. The internal capacity of the sylphon tube when compressed on to the stop was 47.5 cu. centi-metres. We have tried a spring working against the sylphon tube and find that if we have a spring which gives 30 lbs pressure, the valve does not quite open fully until the water is boiling. We have also, at your suggestion, fitted an extension on to the valve operated by the thermostat and by means of a glass tube inserted in the bend we can watch the action when the engine is running. The latest thermostat which we have fitted keeps the water at a very constant temperature, it only varies about 2°. We think it very possible that the variation found on the first valve was due to the fitting. Hs.{Lord Ernest Hives - Chair} | ||