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).
Questioning the use of a non-standard roller bearing crankshaft in a 20/25 single cylinder test unit.
| Identifier | ExFiles\Box 133\2\ scan0012 | |
| Date | 26th March 1934 | |
| X4706 HS{Lord Ernest Hives - Chair} To E.{Mr Elliott - Chief Engineer} From Sg.{Arthur F. Sidgreaves - MD} Copy to Wor.{Arthur Wormald - General Works Manager}Hs.{Lord Ernest Hives - Chair} E.Dx. re 20/25 Single Cylinder Unit. I have read with interest Hs{Lord Ernest Hives - Chair}/CHP.2/KW.21.3.34. There is one point which struck me particularly and which I do not understand and that is that this single cylinder test unit has been built with a fundamental part quite different from the standard 20/25, i.e. a roller bearing crankshaft instead of what we normally use. It seems to me that this will greatly destroy the utility of the unit for testing many things. The report straightaway indicates that the very fact that this roller bearing crankshaft is used causes less oil to be thrown up into the cylinder than is the case with a normal engine. Therefore, it seems to me that, if one wanted to test, say, the pistons in this unit, it would not be of real value to do so because one could only try to reproduce the normal lubrication by abnormal methods. I appreciate that for testing out types of timing, valve lifts etc. this point does not arise and I should be very glad to hear why this departure from standard has been introduced. Sg.{Arthur F. Sidgreaves - MD} | ||