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 discussing a setback with AC.9 connecting rod bearing experiments which resulted in a split bearing.
| Identifier | ExFiles\Box 148\1\ scan0325 | |
| Date | 26th May 1941 | |
| 1256 WORKS TELEPHONE LYMINGTON 520 WORKS TELEGRAMS "WELLWORTHY" PRIVATE TELEPHONE LYMINGTON 232 WELLWORTHY PISTON RINGS LTD., LYMINGTON HANTS MANAGING DIRECTOR'S OFFICE JH/KES 26th May, 1941. W. A.{Mr Adams} Robotham, Esq., Messrs. Rolls-Royce Ltd., DERBY. My dear Robotham, I would like to try and get up to have a word with you on the subject of AC.9 Bearings. I have just been for a visit to Bristol and am sending a copy of this letter to Mr. Hall. As you know, it was a question of whether Bristol should try out the AC.9 or AC.9(a) on their connecting rod bearing. The experiments on the single cylinder set had gone very satisfactorily but the difference of location was greater on the main engine set. We worked out a scheme of location on the outside of the flange and then allowed for a 4½ thou. interference fit when putting the bearing on. Unfortunately it was a very cold night after the bearing had been put on and the 4½ thou. interference fit split it. The technical experts at Bristol say they could not do with anything less than 4½ thou. interference as they would only have 1 thou. interference to enable the bearing to grip the shaft at running temperatures. Mr. Fedden then asked me whether we wanted him to go on with the experiment in view of this set-back. Knowing that all his staff were more or less against going on with the experiment and thinking that possibly there might still be a lot to learn about the material, etc. and also that there was some possibility of attaching it either to a bronze or a steel shell, (Mr. Devereux's people are trying to do this), I suggested the experiments should be suspended for the time being. I think, however, that perhaps you might be interested in having a look at the bearing that split and then pass it along to Mr. Hall. I would like his expert comments as to | ||