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).
The chemical composition and hardness specifications for piston rings and cylinders, comparing American standards with internal ones.
| Identifier | ExFiles\Box 148\3\ scan0177 | |
| Date | 19th November 1936 | |
| FILE 1256 19.11.36. PISTONS RINGS AND CYLINDERS ETC. Extracts from:- Aircraft engine piston ring and cylinder wear. Robert Insley. Read before S.A.E. Jan.1936. ----------- PISTON RINGS. Standard Chemical composition of normal ring material as used in America. Combined Carbon:- 0.50 - 0.75% Graphitic Carbon:- 2.70 - 3.15% Manganese:- 0.45 - 0.80% Phosphorous:- 0.45 - 0.75% Sulphur:- 0.09% max. Silicon:- 2.55 - 3.15% Our normal piston ring Iron is as follows:- Combined Carbon:- 0.40 - 0.60% Graphitic Carbon:- 2.60 - 2.80% Manganese:- 0.70 - 1.30% Phosphorous:- 0.70 - 0.90% Sulphur:- 0.05 - 0.11% Silicon:- 1.60 - 2.3 % Titanium:- Max. 0.25% Hardness of rings to American specification averages about 102 Rockwell B. This material can be used satisfactorily in variety of cylinder metals from S.A.E. 1050 to nitrided cylinders. States definitely that unit pressure of rings should not exceed 35 lbs./sq.in. if excessive wear is to be avoided. This is based on actual results of service experience. continued. | ||