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).
Report discussing the failure of an exhaust manifold and proposing a new design with a cast iron silencer box.
| Identifier | ExFiles\Box 5a\3\ 03-page022 | |
| Date | 3rd May 1917 | |
| To H.R. From G.W.H. Y5840. Hotel de France, Chateauroux, France. 3/5/17. We were held up to 19.3.17 yesterday the 2nd. inst as we wanted all hands to finish off 2D-AA.{D. Abbot-Anderson} We did a trial on 2D-AA{D. Abbot-Anderson} last night with the new torque reaction dampers fitted, with 50% less loading than previous. The results were very gratifying with regard to torque reaction and to boom. The movement of the mixer, however, is not sufficient, so we say that we have gained no 'tittle' results. Here this morning for 7min. and 10.4.17 has resumed running. Re. the 25 HP Exhaust. We are more or less coming to the conclusion that the failure of the exhaust manifolds is due to the stresses placed upon it by the down-take pipe. Previously on 19.3.17. we had fitted a new design of box for the u/by as shown on Job.1241. The material being thinner than standard had buckled. This, apparently with the bending stress to take place on the downpipe as it was acting more or less like a spring, because immediately we changed this stay and fitted the original one, the exhaust manifold cracked during the next 100 miles. We should like to try, from conclusions made, a straight downpipe with a small cast iron front silencer box. We say cast iron for because we want to cut out the tinny noise made by the exhaust with the thin sheet-metal box. We believe apart from the silencer noise, it would overcome the stresses that are set up in the exhaust manifold, and instead of worrying about redesigning the exhaust manifold, we tackle what we believe is the cause. If you are in agreement with us, would you please let us have a straight downpipe, exhaust from front expansion box, with the necessary length of pipe leading from it to connect up to the sliding joint. We should also like to point out that our previous scheme of 'sliding joint' that was made at Chateauroux would function better than the scheme now used, as it acted as a stay besides being a sliding joint. G.W.Hancock. | ||