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).
Defects in an India Front Axle forging that are causing it to twist.
| Identifier | WestWitteringFiles\N\October1925-December1925\ Scan5 | |
| Date | 2nd October 1925 | |
| TO DB.{Donald Bastow - Suspensions} FROM DA.{Bernard Day - Chassis Design} Copy to HS.{Lord Ernest Hives - Chair} ORIGINAL. DA{Bernard Day - Chassis Design}3/M2.10.25. INDIA FRONT AXLE. X 52720 With reference to these axles twisting, we send herewith N.scheme 2061. shewing how we should like the end of the axle forging modified to increase torsional rigidity at the set up ends. As compared with previous instructions the modification we here propose is to increase the thickness of the flanges towards the outer end. The instruction to move the end of the panelling back 1" has already been given, and we believe by now carried out. Measuring the axle forging we have here we are surprised to find that it does not agree with either the original WW. design, or the Derby detail drawing. At the end of the panelling, instead of the web tapering in thickness so as to run out to the outside of the axle without a depression, as is shewn on the above 2 drawings, and is actually done on the 40/50 axle, the central web has been carried straight through about .4" thick only, and where the panelling finishes, comes out with a radius. The effect of this difference is very much to reduce the strength of this part of the axle section in torsion, and we believe is sufficient to account for the axles twisting. In addition to this defect the forging also appears to be about .1 too narrow in the cross section at the point where the panelling finishes, compared with the Derby detail drawing. DA.{Bernard Day - Chassis Design} | ||