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).
Endurance tests for Phantom III bearings and the effects of an oil cooler.
| Identifier | ExFiles\Box 131\5\ scan0023 | |
| Date | 15th November 1937 | |
| Rm.{William Robotham - Chief Engineer} from Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}3/R.15.11.37. P.III BEARINGS & OIL COOLER. In order to compare the results obtained with and without the oil temperature regulator, two endurance runs of 22 hours were carried out under precisely identical conditions with the exception of the oil inlet temperature. This in one case was kept at 90-95°C and 120°C in the other, which is representative of with and without the regulator. As observed from the attached photo of the two sets of W/M standard main bearings, there is little to choose between the resultant condition, the front, centre and rear main bearings being in good condition with the intermediates cracking up in each case. It must be pointed out that these runs were made with Hall's metal bushed big end bearings and standard W/M blade rod bearings. The W/M blade rod bearings showed no difference after running under the two temperature conditions. These runs therefore do not apply to the existing production where W/M big end bearings are used for both the forked rods and the blade rods, and only by running further endurance with these standard W/M big end bearings could we know definitely what the effect of deletion of the oil temperature regulator would be. The effect of this has also been taken regarding the oil temperature when warming up from cold, these comparisons having been taken on the Test Bed. Running light at 1000 R.P.M. for 10 mins, the water temperature rises to 70°C and the oil inlet temperature to bearings to 38°C without the oil temperature regulator. Over the same time with the regulator, the water temperature rises to 70°C, and the oil temperature to 42°C. The effect on the tappet clearance which is almost negligible is as follows:- Clearance cold ............ .010 After 10 mins. without the regulator .013 " " with the regulator ....0125. Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} | ||