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).
Letter detailing the results of endurance tests on several sets of taper valve springs, reporting breakages and requesting further investigation.
| Identifier | ExFiles\Box 80\3\ scan0220 | |
| Date | 10th October 1912 | |
| Copy EP{G. Eric Platford - Chief Quality Engineer}56/T161012 X374 Mr Madin 10/10/12 RE TAPER VALVE SPRINGS. To confirm consultation re above I send you herewith another spring which has broken whilst under test, having run 20 hours on the test rig. Will you please return same for investigation to the makers as we do not think the breakage is due to a flaw. The summary of the test with these springs is therefore as follows :- (Handwritten annotation: special washers, valves etc.) 1st set 6 Run 10,000 miles 2 breakages as already reported. [Handwritten '1st' is struck through] 2nd set 6 with standard valves and washers run 10,000 miles no breakages. 2nd set 6 with special washers and valves run 10,000 miles no breakages. [Handwritten and struck through: 2nd set 6. with standard washers & valves 10000 miles no breakages.] 3rd set 6 with special washers valves one break 20, hours running, miles. | ||