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).
Responding to questions about the use of Discol fuel and its effect on pump diaphragms.
| Identifier | ExFiles\Box 149\6\ scan0105 | |
| Date | 5th November 1937 | |
| To By.{R.W. Bailey - Chief Engineer} from Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems} 1263 Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems}1/MH.{M. Huckerby}5.11.37. In answer to questions attached to memo C/10/0.2.11.37 (attached herewith) regarding the use of Discol. (a) We are aware that Raymond Mays was using Discol without trouble but have not the information as to what type of diaphragm he is using. (b) The Cleveland Discol Co., were approached by the S.U.Co., regarding the failure of diaphragms owing to the action of Discol. They have given their assistance by running both oil silk and Neoprene Fabric diaphragms experimentally. The G.5 oil silk is now fitted to all the pumps produced by the S.U.Co., but the neoprene is only in the experimental stage. The G.5 material was seriously affected by the Discol which removes the dressing from the fabric and also dissolves the oil on the silk as well. However, the combination of oil silk between the G.5 material appears to be remarkably resistant, either the oil dressing re-sealing the G.5 or else the G.5 absorbing the pyridine in the Discol. On our own tests in France we have not had a single failure with the G.5.S material and the running has been done on Azure and Esso alternately containing 15% and 5% alcohol. The S.U.Company have had none of these diaphragms returned for porosity except when the oil silk had been damaged in assembly. They state a considerable number of their pumps fitted to S.S. cars use Discol, and they have not had any returned. (c) LP{Mr Lappin}'s car covered 10,000 miles on Discol when the diaphragms became porous but the pump did not fail. These were poor quality G.5 without the addition of oil silk. We have found that this material without oil silk is inconsistent and may become porous after 6,000 miles. There was no shrinkage of these diaphragms. (d) We have attempted to run endurance with Discol, but it picks up water from the atmosphere and also the small quantity in use does give a comparison to the quantity passing through the pump in a car, in say, 10,000 miles running. Both the oil silk and the G.5. were tested for shrinking by being boiled in Petrol and Alcohol when it was almost impossible to record any change in length. | ||