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).
Technical memo discussing chassis frame stiffness, comparing the existing channel cross section with a proposed I-section.
| Identifier | ExFiles\Box 99\2\ scan0060 | |
| Date | 21th October 1937 | |
| To:- Rm{William Robotham - Chief Engineer}/Mr. Leslie. 200B Dor{Mr Dorey}/Hks.2/FLP.21.10.37. 427 CHASSIS FRAMES. I have looked into the questions you raised during my recent visit to Derby, working on the prints sent later. By replacing the existing channel cross with an I section cross of equal weight, the stiffness of the frame theoretically remains the same, but practically a slight gain in stiffness by using the I section may be expected owing to the greater stability of the flanges in this case compared with the channel section. A satisfactory I section can be therefore obtained from the present channel sections by using the same flange and web areas and shapes. With regard to the intersection point of the cross, it will be realised that the attachment indicated on FB. 2967 differs from that on the Oldsmobile chassis to the extent that in the former case, the attachment plates etc., have to primarily transmit bending, while in the latter case, shear is transmitted by the plates. It is considered that with I section members and welding, as on the Oldsmobile, the construction of the joint adopted on what chassis is the stiffer. The length-depth ratio of the beam shown on FB. 2967 appears to be quite suitable for the order of stiffness required. Dor{Mr Dorey}/Hks. | ||