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).
Failure of Phantom III rear brake drums and suggesting potential causes and design improvements.
| Identifier | ExFiles\Box 92\4\ scan0106 | |
| Date | 8th November 1935 | |
| x306 HS{Lord Ernest Hives - Chair}/AFM{Anthony F. Martindale} Hs{Lord Ernest Hives - Chair}/RM.{William Robotham - Chief Engineer} from E.{Mr Elliott - Chief Engineer} c.c. By Hs{Lord Ernest Hives - Chair}/AFM.{Anthony F. Martindale} c.c. Hs{Lord Ernest Hives - Chair}/CWH (at Chateaudoux). E.2/HP.8.11.35. Phantom 3 Rear Brake Drums. Referring to Hs{Lord Ernest Hives - Chair}/AFM.{Anthony F. Martindale}21/KW.7.11.35, I cannot quite understand the reasoning of this memo, in which the flexing of the drum is advanced as the cause of the breaking off of the thin drum edge. Surely the stress range and maximum stress in this thin edge is nothing like that which occurs in the first rib as it should be in proportion to the relative depth of section. I think it may be a wise policy to increase the ribs to 1" deep for other reasons, but we ought to know how much of the edge is involved in the pieces that have come off the drum, and whether the bombardment of stones that this thin drum edge receives have had anything to do with the failure. E.{Mr Elliott - Chief Engineer} | ||