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).
Summary of front spring rating tests with data tables and graph references.
| Identifier | WestWitteringFiles\O\2April1926-June1926\ Scan161 | |
| Date | 27th May 1926 | |
| Attached to :- Hs{Lord Ernest Hives - Chair}/RuL/T27.5.26. FRONT SPRING RATING TESTS. α Wide axle pad. 21° forward shackle. Bump loading. δ Narrow " " " " " β Wide " Vertical shackle. " ε Narrow " " " " γ " " 10° inward shackle. " η Wide " 21° forward shackle. " Woodhead's spring. βII " " Vertical shackle. Gradual loading. εII Narrow " " " " γI " " 10° inward shackle. " γII = (ε corrected) Narrow pad, vertical shackle, Bump loading. | | Mean Rating. 200-1200 lbs. (lbs/in) | Mean Rating. 1100-1900 lbs. (lbs/in) | % Variation (approx). increase or decrease | |---|---|---|---| | α | 372 | 409 | + 10% | | δ | 358 | 393 | + 9.8% | | β | 358 | 360 | + 0.6% | | ε | 341 | 342 | + 0.3% | | γ | 344 | 345 | + 0.3% | | η | 404 | 444 | + 10 % | | βII | 372 | 382 | + 2.7% | | εII | 352 | 357 | + 1.4% | | γI | 340 | 344 | + 1.0% | GRAPHS:- 1. (α) & (β) Effect of shackle angle - Wide pads - Bump loading. 2. (δ) & (ε) " " " " - Narrow " - " " 3. (β) & (ε) " pad width - Vertical shackle -Bump loading 4. (α) & (δ) " " " - 21° forward " - " " 5. (δ) & (η) Comparison of spring systems. (Narrow pad + 21° forward shackle) Bump loading 6. (α) & (ε) " " " (Wide " + vertical ") Bump loading 7. (ε) & (εII) Effect of internal friction - Narrow pad - Vertical shackle 8. (β) & (βII) " " " - Wide " - " " 9. (α) & (β) Shewing agreement of independent tests - Bump loading. 10. (γ) Effect of shackle movement deflection - narrow pad - 10° inward shackle - Bump loading. 11. (γ) Variation in shackle angle - Narrow pad - 10° inward shackle. Contd. | ||