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).
Continued report on pivot durability tests, comparing different models and noting contradictory results potentially related to heat treatment.
| Identifier | ExFiles\Box 2\B002_X168\ 00000001-page220 | |
| Date | 7th January 1914 | |
| J.{Mr Johnson W.M.} for H.{Arthur M. Hanbury - Head Complaints} 7.1.14. Da{Bernard Day - Chassis Design}7/6d114 Cont. -2- did not make this section weaker than the U, or appreciably affect its strength. In tests over obstacles AV/HGR/L17113, and Wer/Ry1/L5713, and F.3253 type pivot ran 540 minutes and then broke in the U, but F.3372 ran for 1810 minutes and showed no signs of breaking, not even being out of truth. Against this must be set the frame bumping tests, where a F.3253 pivot stood for 12 hrs. 37 mins. and then broke in the U, while F.3372 did 6 hrs. 3 mins. and F.3697/8 (the same as F.3372 but 1/8" shorter in the stub) 7 hrs. 37 mins 12 hrs. 47 mins. and 10 hrs. 32 mins. These results are somewhat contradictory, and seem to point to heat treatment or steel as something to do with it. The heat treatment employed by Vickers (the pivots are not treated here) is 800 C and 550 C, the same as you recommend. Da.{Bernard Day - Chassis Design} [Initials] | ||