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).
Shock damper knocking issues, bearing materials, and setting damper loads for chassis CHG-1.
| Identifier | ExFiles\Box 27a\1\ Scan428 | |
| Date | 7th May 1936 | |
| W/P - Sr/VA. X1245 Hs{Lord Ernest Hives - Chair}/Les.5/KW.7.5.36. Thank you for your Sr/VA2/ET.30.4.36. At the moment we are inclined to agree with your results from chassis CHG-1, namely, that the slightest slackness of the main lever of the shock damper in its bearings will cause a knock. For this reason we are trying several different bearing materials. With regard to setting the loads of dampers. Our method is identical to yours. Actually the time factor makes a lot of difference. We generally take the load of a fairly slow movement of the lever provided it is fast enough to raise the shock damper valve. Experimentally we check the pressure rise due to increased speed on an indicator diagram. This gives the general damper characteristic, but is only used when altering any essential part of the damper There is always a difference in loads of dampers set in the Experimental Dept. and production. We are generally more energetic than production. We shall certainly be very interested to hear any information you may gain re shock damper knocks. The clearance between the intermediate lever and the bushes is at the present on the list of alterations which do not affect damper knocks. With regard to clearances in bearings, we should be very interested to have your opinion as to whether these are due to initial slackness or wear. Wear can generally be distinguished by the bush being oval in bore. The shafts do not seem to wear noticeably. Now that you have some replacement dampers, you will be able to collect some real knocking dampers, these will be very gratefully accepted. Hs{Lord Ernest Hives - Chair}/Les.{Ivan A. Leslie} | ||