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).
Engineering drawing for an inner valve spring for a Humber Hillman 6 cylinder engine.
| Identifier | ExFiles\Box 126\2\ scan0043 | |
| Date | 26th June 1936 | |
| MODIFICATIONS SHEET DATE SGN Handwritten: Sliding closed 1.66, Mean 70.0, clash 81.5 SK. ENDS TO BE SQUARE WITH AXIS OF SPRING. IMPORTANT:- OUTSIDE DIA TO BE A TELESCOPIC FIT IN OUTER SPRING P.53372 AT FITTED LENGTH. IMPORTANT:- INTERNAL DIA TO BE A FREE FIT ON .654" DIA. TO BE FITTED AS PAIRED WITH P.53372 BY MAKERS. TABLE: SECTION OF WIRE: 0.104" (12 S.W.G.) No. OF FREE COILS: 9 *INTERNAL DIA: SEE DRG *RATE: 43 LBS PER INCH FREE LENGTH: 57 m/m FITTED LENGTH: 41 m/m *TO EXERT 27.5 ± 1/4 LBS AT 41 m/m TO WORK SAFELY AT 33 m/m fs{F. Steele}=70,500 LBS. PER SQ: INCH. *SOLID LENGTH NOT TO EXCEED 29 m/m fs{F. Steele}=81,500 LBS PER SQ: INCH *HAND OF SPIRAL: R.H. FINISH: NATURAL *IMPORTANT TITLE BLOCK: HUMBER HILLMAN 6 CYL: COMPNT: ENGINE - VALVES PART: VALVE SPRING (INNER) NUMBER: P53371 STAMP & APPROVAL BLOCK: HUMBER HILLMAN COVENTRY DRAWN TRACED: P.L.A, 21.4.36 CHECKED: J.G, 22.4.36 PASSED SPECD DATE STAMP: 26 JUN 1936 f: MACHINED FINISH H: HARDENED G: GROUND m: MACHINE ALL OVER r: ROUGH MACHINE HEAT TREATMENT WEIGHT LBS OZ ROUGH FINISH MATERIAL: STEEL SPECN: AERO QUALITY FORM: FIN SECTION LENGTH Note:- ALL UNLIMITED MACHINING DIMENSIONS TO BE WITHIN +.200 m/m -.200 m/m | ||