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).
Proposed rig tests for a modified lubrication system on Kestrel main bearings following recommendations from Allison.
| Identifier | ExFiles\Box 173\2\ img035 | |
| Date | 6th February 1934 | |
| Aero Orig? E.{Mr Elliott - Chief Engineer} B.? Indianapolis, Indiana February 6, 1934 To HS{Lord Ernest Hives - Chair} from RHC{R. H. Coverley - Production Engineer} In view of Allison's recommendations regarding modified lubrication system for Kestrel main bearings, we thought perhaps you would consider it worth while conducting a series of rig tests so that some data can be obtained. The test suggested as follows: A.{Mr Adams} Ascertain oil pressure at crank pins with standard grooved type bearings. B. Test plain bearings having additional holes to ascertain pressure in crank pins. C. Conduct test to ascertain minimum bearing clearance and effect of reduced clearances in crank pin pressure. D.{John DeLooze - Company Secretary} Additional hole in crank webs to obtain continuous feed through crank and difference of oil pressure in crank pins. For the purpose of tests, big end bearing blocks could be fitted to the crankshaft but with oil feed holes for inner connecting rod plugged. The bearing would be given the standard clearance so as to allow oil to flow and give somewhat representative bearing conditions. Each crank pin would be fitted with spring loaded cartridges calibrated to give pressure readings which would be checked at various speeds and under same oil pressure and temperature (90° C.) conditions. Cartridges referred to were made some time ago and operated satisfactorily. One reason for the test is that we are of the opinion that when Allison's adopted the grooveless bearings, it was found necessary to drill crank up web to provide sufficient lubrication for connecting rods in addition to obtaining the continuous flow through crankshaft. It would in addition, settle the point as to whether there is any variation of oil pressure in crank pins under standard conditions. | ||