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).
Works chemist's report discussing petrol-related corrosion and gumming issues on tank attachment parts.
| Identifier | ExFiles\Box 149\4\ scan0190 | |
| Date | 17th February 1937 | |
| COPY OF MR. FRANKLINS(WORKS CHEMIST) REPORT dated. '17. 2. 37. (1) As suggested by Mr. West, of Rolls Royce Ltd., I interviewed Mr.F.R.Banks and discussed the subject of petrols and liquid fuels and their possible effect on Tank Attachment parts as manufactured by S.Smith & Sons (MA) Ltd. (2) The corrosion of Cadmium plated brass floats and gears in certain tank attachments was, in Mr. Banks opinion, mainly due to Sulphur attach, arising from the Sulphur content of the various types of petrol. It would be his considered opinion that Cadmium, Zinc, or Nickel deposits would be unsatisfactory for prolonged exposure to Sulphur bearing petrols and that Tin plating should be a distinct advantage as Tin should satisfactorily resist any tendency to corrosion from Sulphur attack. It is highly significant that most petrol tanks are made from tin plate and that they give satisfactory service. The above expression of opinion completely confirms our previous findings and reports on this matter. (3) As entirely new light, however, was thrown by Mr. Banks on the subject of the stickiness of tank attachment parts and the hitherto puzzling occurrence of a resinous or varnishy deposit on floats. Mr. Banks stated that most of the commercially 'cracked' spirits used so commonly to day, contained varying amounts of olefine hydrocarbons etc., which when stale and subjected to prolonged exposure to air, were liable to oxidise and form a gum. In the United States, he had frequently seen petrol tanks gummed up with a sticky substance like molasses and it was fairly well established that this sticky substance was a gum resulting from the oxidisation of the hydrocarbons such as the olefine series. With cars out of commission for any lengthy period, it was quite possible for the gum to accumulate and increase in concentration owing to the evaporation of the more volatile constituents of the petrol. In such cases, especially if the original 'cracked' petrol was at all stale, an appreciable stickiness could result. | ||