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).
Cylinder head hardness, Brinell testing, and a potential valve seat erosion issue.
| Identifier | ExFiles\Box 5a\2\ 02-page358 | |
| Date | 24th December 1930 | |
| c. Hs.{Lord Ernest Hives - Chair} X5840 BY2/G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 24.12.30. RE REPORT ON 18-G-4. SECOND ITEM - PAGE 1. CYLINDER HEAD. All cylinder heads as well as cylinder blocks are individually brinell tested for hardness, and no cylinder head or cylinder block is passed out for production unless up to the brinell figure. The brinell range is 202 to 229. Generally speaking the brinell figure shows a hardness of 217. We consider that the effect which GEH. calls "hammering" is our old experience of valve seat erosion, which arises occasionally on cast iron. It is similar to the effect we used to get on the Eagle engines under certain service conditions. We will arrange to inspect the head when the engine comes back to check the above, but we do not think that the actual hardness is the cause of the trouble. By BY.{R.W. Bailey - Chief Engineer} | ||