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).
Proposal to experiment with a magnetic oxide coating as an anti-corrosion method for exhaust systems.
| Identifier | ExFiles\Box 66\2\ scan0185 | |
| Date | 16th April 1926 | |
| X8230 HS. {Lord Ernest Hives - Chair} RHC. {R. H. Coverley - Production Engineer} BY6/H. 16.4.26. I wish to try out another method of protecting the exhaust system against corrosion. At present we are experimenting upon:- a {Mr Adams} /- Calorized Mild Steel tubes. b/- 'Staybrite' Steel tubes. The further proposal that I am now putting forward is that we should try tubes protected by the production of magnetic oxide internally and externally on all surfaces exposed to heat. The benefit of this would be that it would not be nearly as expensive as Calorizing, and would be more easily handled, in as much as the magnetic oxide is nothing like as hard as the alumina (oxide of aluminium) produced by the Calorizing process, therefore it would be possible to supply parts, even if not in the finished condition, in such a condition as to enable us to protect surfaces which would be finally exposed, and machine away (for instance inside bosses and flanges) the treated surface where it had to fit on the tube. Would you kindly let me have two complete sets of exhaust connections in the unbrazed condition, including silencers. None of the parts would have to be brazed up where brazing is called for; the units which would finally be brazed together should be supplied separately, but preferably I would like them marked with a light paint on the surfaces where we do not want them treated, as I intend to have the parts, if possible, treated only where required, although I am afraid the process is such as not to make this possible. The exhaust snout should be supplied without being dipped in brazing metal, as I intend to try and protect this in a similar manner by the deposition of magnetic oxide. The process I intend to try, has, I think, the following characteristics:- 1. An oxide is produced by super-heated steam on heated metal. The oxide produced is, however, a mixture of magnetic oxide with sesqui-oxide of iron. The latter, however, can be transformed into magnetic oxide by raising the temperature of the parts after Con. | ||