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).
On the failure of a plated mild steel exhaust downtake pipe and suggestions for alternative materials or treatments.
| Identifier | ExFiles\Box 152\3\ scan0243 | |
| Date | 18th March 1938 | |
| 1297. Km/Wyatt Rm.{William Robotham - Chief Engineer} BY.7/G.18.3.38. EXHAUST SILENCER AND FITTINGS. RE: CHEAPER MATERIAL FOR DOWNTAKE PIPES. In examining the sample tube returned from France, which had failed, the tube in question being a mild steel tube, plated inside and outside, the conditions are not as favourable as would appear, for whilst the tube appeared to be intact, as a matter of fact it was completely oxidised throughout, so that all that remained was oxide of iron encased between the two nickel coverings; the tube was so brittle that one could break it with the fingers alone, and wherever it was broken it exhibited complete oxidation of the steel, so that it is evident that no more slight change of material could possibly get us out of this difficulty. There is one method of protection which deserves further experimental work viz. the treatment of a mild steel tube with chromium and nickel compound in a similar manner to which one would carburise a piece of steel and by the treatment in question completely altering the outer and inner skin of the tube, so as to make the surface of the tube practically Staybrite material. A process of this type is practised by the Follsain Co., and I would like to have a downtake pipe completely welded up and ready for fixing, which could be treated in this manner. If this were to fail, I am afraid we then have no prospect of succeeding with anything short of the normal Staybrite type of austenitic steel i.e. 8% nickel and 18% chromium composition. BY.{R.W. Bailey - Chief Engineer} | ||