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).
Analysis of component failure in a spring and washer assembly, including hardness test results and proposed modifications.
| Identifier | ExFiles\Box 36\1\ scan 145 | |
| Date | 22th November 1927 guessed | |
| contd :- -2- A further increase would be possible if we could grind a small radius or chamfer on the end coils (internally) of the inner spring when 'A' could be made .725" (-5). Short of altering the spring, the thickness of the metal at 'B' can only be increased by alterations to the bottom spring washer - such as making the latter integral with the valve guide. Brinell hardness tests taken on several samples of the fractured washers give lower figures than the hardness called for on E.30837. Fractured samples 262/282 brinell. E.30837 calls for 302/321. It has been observed that before the washers fracture, the split collars E.24310 slowly sink below the top of the washer in the manner shewn by the dotted lines on the sketch, until the resultant force due to the spring loading etc. is taken across the weak part of the collar where the fracture occurs. Hs{Lord Ernest Hives - Chair}/V.Halliwell. | ||