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).
Letter from a piston ring manufacturer discussing the performance of cell-faced and tin-plated rings.
| Identifier | ExFiles\Box 148\1\ scan0051 | |
| Date | 22th February 1939 guessed | |
| WELLWORTHY PISTON RINGS LIMITED CONTINUATION No. 1. Department that they have tried the cell-faced ring, and although in the first trial made the oil consumption went up, modification of the process to suit their requirements has resulted in a reduction of oil consumption and has eliminated scuffing. We have, as you will therefore realise, several irons in the fire, and we would not recommend one thing to the exclusion of all else, but rather try to apply different rings or types of finishes to particular cases in hand. The same thing applies to tin-plated piston rings. As you are probably aware, these have been on the market for about two years in this country by Hepworth & Grandage, and laterly by Light Production Co, and we ourselves are laid down for tinning cell-faced rings, where we believe that it is wise to modify the slight initial wear which can be caused on cell-faced rings due to slight abrasion by the phosphide eutectic. Tinning has been approved by a number of engine builders as a definite advantage, although in our opinion it wears off very quickly, and does not last for such a long period as the cell-faced ring, the sole object of which is to carry sufficient quantity of oil at all times to prevent scuffing. Once the cylinder surface has acquired that well-bedded in finish there is very much less chance of scuffing taking place, and we believe by our method we achieve the desired object. Incidentally, have you yet tried the cell-faced ring in your engines ? It would be interesting to know what the results have been, providing that is that you have certain conditions which at the present moment give the troubles of dry scuffing, and it would be interesting to know how they compare with quick-bedding in as against the "L" section rings. Yours faithfully, For WELLWORTHY PISTON RINGS LTD., [Signature] Technical Manager. | ||