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).
Material standard specification for valve spring steel wire.
| Identifier | ExFiles\Box 158\4\ scan0061 | |
| Date | 28th September 1936 guessed | |
| MATERIAL STANDARD C. S. V.{VIENNA} 2 VALVE SPRING STEEL WIRE 1. This specification covers an excellent grade of valve spring steel used by 2. STEEL MANUFACTURE: - This steel is to be made according to approved practice by the electric or open hearth process. 3. CHEMICAL COMPOSITION: - Carbon .65 - .70 Manganese .45 - .65 Sulphur .025 max. Phosphorus .025 max. 4. PHYSICAL PROPERTIES:- Tensile strength size .128 or smaller - 205,000#/sq. inch min. " " " .135 - .177 - 200,000#/sq. inch min. " " " .187 or over - 195,000#/sq. inch min. Reduction of area 45% minimum. Torsional Properties Size .177 or less Elastic limit 105,000 #/sq. inch min. Ultimate - 160,000 #/sq. inch min. Size .187 or over Elastic limit 100,000 #/sq. inch min. Ultimate - 150,000 #/sq. inch min. Twist Test: - Samples taken from any part of the bundle of wire must stand 7 twists forward and reverse as shown on chart to a clean square break. CHART Use 10" specimen. #13 #12 1/2 #12 #11 1/8 #10 Size .0925 .098 .105 .120 .125 .135 Reverse Twist 26 25 24 21 20 20 | ||