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).
Phantom III rear axle oil seal tests using double oil seals.
| Identifier | ExFiles\Box 92\5\ scan0173 | |
| Date | 25th August 1939 | |
| 302. To Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} from HPS{Horace Percy Smith - Experimental Factory Mgr}/B1. c.c. to Dcr. c.c. to Hcy. c.c. to Ry. HPS{Horace Percy Smith - Experimental Factory Mgr}/B1.1/IC.25.8.39. Phantom III Rear Axle Oil Seal Tests. Double Oil Seals. G.C.D. 1340. For the purposes of this test which was carried out according to scheme G.C.D.1340 a special shaft BL.1078 and housing BL.1077 were made, the latter being such that it would accomodate two "Perfect" Oil Seals, No.200112, provision being made for detecting any leakage past the seals. A means of supplying oil to the seals, either under pressure or gravity feed, was also included. As instructed, the space between the seals was packed with grease, the standard bearing grease, Duckhams' "Adcol", being used. In order to see whether the grease itself tended to escape during running, the shaft was run at a speed of 1000 r.p.m. for about 300 hours, without any external oil feed. During this period no leakage of grease was observed, and on removing the housing for closer inspection it was seen that the grease was still absolutely intact, and no scoring of the shaft had taken place. Standard gear oil Castrol X.L.30 was then fed to the seals under a pressure of 5 lbs/sq.in., the shaft being again run at 1000 r.p.m. Under these conditions there was a slight leakage of oil past the seals, this being of the order of one drop every twenty minutes; after about ten hours this increased to one drop every ten minutes. The leakage remained constant at this value for a further 30 hours, after which time the shaft was stopped, and the housing removed; examination revealed that the greater part of the grease had apparently dissolved in the oil and leaked away with it. Definite signs of grease were seen to be present in the oil which had leaked through the seals. The above test was repeated with the oil pressure reduced to that due to a head of 1 ft. of oil; in this case, there was no leakage during the 20 hours for which the shaft was run. (continued.) | ||