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 Hardy fabric couplings, detailing different setups and failure modes.
| Identifier | ExFiles\Box 5\5\ 05-page16 | |
| Date | 15th July 1929 | |
| X512. HARDY FABRIC COUPLING TESTS These tests were run on a joggling rig of similar dimensions to that used some time ago. In this case however, the power was supplied by a D.C. variable speed electric motor through a 20 HP. gearbox to the fly-wheel crank, whereas, previously the flywheel was driven direct from the shop power shaft. TEST No 1. This fabric was to G.77760, dimensions, but the drilling sizes of the small plate holes, which were decreased to take rivets G.73572. In place of the standard screws and nipples G.74628/9. The method of attaching the fabric to the spiders is shown in EX.3958, i.e. using solid-spigotted studs. There were no pressure plates used with this fabric. TIME RUN 21 hours 52 mins. REVERSALS 754.922. Fabric collapsed, rivets O.K. TEST No 2a. Fitted up to arrgt. G.77763. - i.e. plates screwed on as standard - and attached to spiders by solid spigotted studs as in Test No 1. The screws and nipples were not locked over in this case and in order to discover whether or not this was the cause of early failure Test 2c. was run. Pressure plates G.74992. were fitted. TIME RUN 1 hour 20 mins. REVERSALS 46.802. Majority of the screws were either broken or loose. TEST No 2b. This was a repeat test of No 2a, the screws in this case being burred over. After 1 hr. 30 mins. it was stopped and examined. Several screws were found to have slackened, and two were broken. The fabric was refitted without alteration and the test continued. TOTAL TIME RUN 2 Hr. 20 Mins. REVERSALS. 62.320. Fabric just collapsing, nearly all screws either loose or broken. | ||