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).
Test report on 'Ebony Sindanyo' insulating material.
| Identifier | ExFiles\Box 24\2\ Scan278 | |
| Date | 20th December 1927 | |
| EFC WC.55 X1109 20.12.27. "EBONY SINDANYO" INSULATING MATERIAL. A sample of the above has been submitted to us for test and we give below the results obtained. (1) Machining tests. Mr. Coverley reports as follows - "This is not at all suitable for general machining; it is soft and drags, consequently difficult to cut." (2) Insulation test. by means of 1 sq. inch plates A D.C. voltage of 10000 volts was applied across the material which is .375" thick and a leakage of only 10 micro-amps. was obtained, giving an insulation resistance of 1000 . (3) A series of tests carried out by the chemical laboratory gave the following results :- (a) Water test. No visible effect; absorbed .6% of its own weight of water. (b) Oil test. Slight softening occurred; absorbed 5.6% of its own weight of oil. (c) Petrol test. The petrol dissolved some oily substance from the specimen. A considerable absorption of petrol also took place the nett gain in weight of the specimen being 8%. (d) Acid test (dilute nitric) The material softened and was slightly attacked and lost 1.3% of its weight. (e) Acid test (dilute sulphuric) The specimen was considerably attacked and disintegrated, and absorbed 31% of its own weight of acid. It will be seen that both petrol and sulphuric acid attack this material considerably and we therefore do not consider that it shows any superiority over that which we are at present using. EFC/HEW. | ||