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).
Letter to the Air Ministry detailing results of engine cooling tests with Ethylene Glycol and proposing to move from single to six-cylinder unit tests.
| Identifier | ExFiles\Box 54\4\ Scan077 | |
| Date | 11th March 1933 | |
| c. to R. {Sir Henry Royce} Sg. {Arthur F. Sidgreaves - MD} c. to Wor. {Arthur Wormald - General Works Manager} Wg. {Mr Gill - Financial Director} c. to C/Ab. HS {Lord Ernest Hives - Chair} /Pkn.8/MA. March 11th., 1933. The Secretary, Air Ministry, Adastral House Kingsway, W.C.2. For the attention of Mr.Tweedie. Dear Sir, We have now completed over 200 hrs. running on Ethylene Glycol with high temperature cooling. The maximum temperature we run up to is 150°C. We have completed 88 3/4 hrs. of the contract time on the 100 hrs. contract for running the single cylinder unit on Ethylene Glycol and a summarised report on the work has been submitted. We have done a considerable amount of running at our own expense in conjunction with other tests and we consider that the position has now been arrived at when tests on Ethylene Glycol should be transferred to a six cylinder unit. We have experienced no constructional failures on the cylinder and we have had no troubles which we consider would lead to difficulties when running the larger unit. The weaknesses which have been shown up on the single cylinder running are:- overheating of the piston crown, weakness in the gudgeon pin bosses, and the unsuitability of ordinary rubber joint rings and hose connections for high temperature cooling. After modifications the piston is now satisfactory and 24 hrs. running have been completed at an outlet temperature of 150°C. All rubber joint rings and hose connections are now produced in a rubber specially vulcanized to withstand a temperature of 205°C. and no trouble with leakage at the cylinder joint ring is now experienced. | ||