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).
Page discussing a spring design formula from a 1925 S.A.E. Journal and introducing a subsequent table of formulas.
| Identifier | ExFiles\Box 158\4\ scan0042 | |
| Date | 12th June 1936 guessed | |
| -5- Then experience gives us the formula, as published by Stewart in S.A.E. Journal of August 1925. d = .48d (O D + 1) ------------- P D For ratio of diameter of wire to mean diameter of spring greater than one to twelve, the effect of keystone can be neglected. After d is obtained, the solid height of the spring can be calculated. For your convenience we have taken the formulas given and tabulated them on the next page. The first column gives the unknown desired and the next the known quantities which must be obtained to solve the equation for round wire compression or extension springs. The last column gives the same information for square wire. | ||