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 development and properties of cast materials for crankshafts.
| Identifier | ExFiles\Box 132\1\ scan0013 | |
| Date | 18th April 1927 guessed | |
| 1116. CAST MATERIALS FOR CRANKSHAFTS. FILE The development and use of cast crankshafts would appear to have made more rapid strides in the United States than is the case in this country. In that country the pioneer work was commenced at an earlier date, and has been since its development more confined to the production for automobile use than in any other line of engineering. The outstanding example of cast material for crankshafts in any one particular manufacturing plant is that of the Ford Motor Company, and at Dagenham, England, at which place can be seen the truly mass production methods employed. The cast material used has steel characteristics in the finished condition, but "as cast" the metal requires heat treatment to effect the maximum physical qualities desired. Cone (Metals and Alloys, V.6, No. 10, October, 1935, pp. 259-263), gives the composition finally decided upon as:- Total Carbon ... 1.35 - 1.60% Silicon ... 0.85 - 1.10% Manganese ... 0.60 - 0.80% Phosphorus ... 0.10% max. Sulphur ... 0.06% " Copper ... 1.50 - 2.00% Chromium ... 0.40 - 0.50% and the heat treatment:- Heat to 900°C., hold for 20 minutes, air quench to a minimum of 650°C. Reheat to 800°C., and hold for one hour, cool in furnace to 550°C., in one hour. Figures given for the properties of the alloy are:- Transverse ... (1" square bar, 12" centre). Breaking Load ... 77.9 Tons per square inch. 75.0 " " " " Deflection ... 0.42" 0.43" Tensile Strength ... 48.2 Tons " " " 47.8 " " " Elongation ... 3.0% Reduction of Area ... 2. 2.6% Brinell Hardness No.... ... 269. 269. | ||