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).
The fitting, chemical properties, and specific weights of a flexible tube.
| Identifier | ExFiles\Box 88\5\ scan0203 | |
| Date | 1st August 1929 guessed | |
| 4. E.2861 These were quite satisfactory and are very easily fitted and have the further advantage in that the ordinary metal tubes can be fitted right into them without any soldering or preparation of the ends. The rubber glands for making these joints were unaffected and the tubes had no apparent tendency to blow out under pressure. The method of locking the gland nut by a spring washer is neat, simple and efficient. Fig.V shews the arrangement of these ends and the method of fitting them. It is emphasised that great care should be taken in stretching, binding and cutting the tube. The tube should be gripped in wood clamps at two places, the point at which it is desired to cut the tube being midway between these clamps. The latter should be drawn apart in order to stretch the tube and so reduce its diameter. The point at which it is desired to cut the tube should then be tightly bound with insulating tape and two turns of wire should be tightly bound round, there being space between these to permit a hacksaw blade to enter. When possible the inside should be supported with a fairly tight fitting wooden rod, but though this is not absolutely necessary it greatly facilitates the cutting. The tube should then be very carefully sawn through between the bands of wire with a new fine saw and no pressure should be put on the saw. Great care must be taken when the wire lining is encountered. The wood, if used, should be cut right through with the tube. After cutting, the wire and insulating tape should be very carefully removed, the ferrule "A" (Fig.V) put over the tube and the inside of the tube and outside of the threaded aluminium end "B" covered with 'Shellac' or 'Hermeticol' for the length of the tapered portion of 'B'. The end should then be screwed in while the tube is held in a clamp and by hand near the joint end, the joint is then complete. Two ends so fitted on each of the two sizes of tubes when tested withstood a pressure of 175 lb.per sq.inch of paraffin before leaking. 5. Chemical Tests A sample of the inner lining of the tube was forwarded to the Chemical department in order to determine its capacity to withstand any destructive effects of hot oil, standard service and doped fuels. A copy of the report from that department is attached. The lining is practically unaffected by ordinary and doped fuels, but becomes brittle when subjected to oil at temperatures of 150°C. It commences to harden slightly at 120°C. but provided this temperature is not exceeded the lining should prove satisfactory. For further details see Chemical Test Report in Appendix I attached. 6. Specific Weights and General This tube is exceedingly flexible and light, the weights being as follow :- 16 m.m. / | ||