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).
Tests and modifications on vents, dampers, and governor control systems, including notes on oil piping and pressure.
| Identifier | ExFiles\Box 179b\2\ img092 | |
| Date | 11th November 1932 | |
| -2- Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}4/A.11.11.32. Cont'd.{John DeLooze - Company Secretary} advantage at the higher temps. of the two vents to the atmospheric chamber will be seen. Generally speaking these diagrams show the damper to be satisfactory when used as a fixed load instrument, provided that the standard of silence we have so far achieved is maintained in service. (II). We found that the air vent to the bearing was too high in the damper. We have left the oil feed to the bearing and, reduced in quantity and put the air vent in the top of the piston as a groove No. 741. Diagrams 15 to 18 show the necessity for a vent, for some reason the L.P. stroke does not require a vent so badly, however we have made both ends of the piston similar for interchangeability. (III). We have done a good deal of rig testing on the governor control. Our first tests showed that with our standard compressor oil .156 piping was too small (Diagrams G.1 to G.4). A .250 diameter pipe gave much better results, the short stroke diagrams being almost ideal (G.5 and G.6) The long stroke diagrams, however, (G.7 & G.8) showed a tendency to fall away in pressure towards the end of the stroke, which we attribute to the increased pressure on the exp leather piston due to the valve spring rating forcing the oil out of the control chamber as the valve lifts, and the pressure not being restored rapidly enough after the oil passing the valve seat has reached a maximum velocity. We are trying 'E's suggestion for overcoming the difficulty, but road tests will show whether this is very serious. G.9 to G.11 show that the low pressure side of the damper behaves in the same way. | ||