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).
Quarterly complaints and tests of fabric couplings, detailing failure causes and replacement recommendations.
| Identifier | ExFiles\Box 47\2\ Scan446 | |
| Date | 19th December 1930 | |
| Wor.{Arthur Wormald - General Works Manager} from Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} c. By.{R.W. Bailey - Chief Engineer} c. Hd.{Mr Hayward/Mr Huddy} 84117 HS{Lord Ernest Hives - Chair}/Rn{Mr Robinson}2/AD19.12.30. QUARTERLY COMPLAINTS. x4117. x7305. x5305. FABRIC COUPLING TESTS. We have been testing three types of fabric coupling, standard, improved standard, and Hermetic. So far our tests indicate that the Hermetic coupling promises a slight improvement, but we shall have to increase the severity of the test to get sufficient information to recommend a change. We find that tremendous differences in life can be caused by (1) Nipping the coupling too tightly when rivetting, this, of course, applies equally to the rivets being too slack. (2) Getting the spiders slightly out of line. The latter happens on our rig because we have no sliding splines, but it should not happen on the car. We only discovered it in trying to explain the large differences shown in our tests. There is no doubt that the rivetted coupling with spigoted spiders is giving us about ten times the life of the original non-spigoted coupling (first 93 Phantom IIs) and about four times the life of the coupling held together by screws which is the one at present featuring in the quarterly complaints rather too frequently. We recommend that, in view of the large differences in life that can be produced by small differences in fitting of the plates to the coupling, the inspection of the finished discs should be carried out with particular care. Our main trouble is not that we have no means of overcoming the failure, but that there are some hundreds of cars on the road with couplings that are likely to fail. To replace these couplings, unless the gear-box happens to be stripped for some other reason, means a very heavy expenditure which is hardly tolerable. The couplings themselves are only worth a few shillings. This being so, we are issuing a depot sheet recommending that whenever a gearbox is removed from a P.II. car the fabric coupling should be changed to the latest type unless this has previously been done. GWH.{George W. Hancock - Head Chateauroux} reported last week that failures of these couplings were becoming more frequent. Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} | ||