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 The Light Production Co. Ltd. proposing a design modification for pistons with raised crowns to ease foundry difficulties.
| Identifier | ExFiles\Box 148\1\ scan0132 | |
| Date | 17th May 1939 | |
| 1256. TELEPHONE: VICTORIA 0671 (6 LINES). ALL COMMUNICATIONS TO BE ADDRESSED TO THE COMPANY. THE LIGHT PRODUCTION CO. LTD PROPRIETORS OF THE LONDON PISTON RING CO. LIMITED. CHAIRMAN & MANAGING DIRECTOR: M.{Mr Moon / Mr Moore} V.{VIENNA} ROBERTS. DIRECTORS: E.{Mr Elliott - Chief Engineer} G.{Mr Griffiths - Chief Accountant / Mr Gnapp} DAVIES, WM. THIRTLE. ENGINEERS 60/66, ROCHESTER ROW, WESTMINSTER, S.W.1 WORKS AND GOODS ADDRESS: 61/67, GREENCOAT PLACE, WESTMINSTER, S.W.1. CODES: A.{Mr Adams} B. C. 5TH EDITION. ON ADMIRALTY, WAR OFFICE AND AIR MINISTRY LISTS. TELEGRAMS: INLAND, NAPOLEONIC, SOWEST, LONDON. FOREIGN, NAPOLEONIC, LONDON. OUR REF. CHB/DP 17th May, 1939. YOUR REF. Messrs. Rolls Royce Ltd., Experimental Dept., DERBY. File Dear Sirs, For the attention of Mr. C.T. Salt. In connection with the manufacture of Pistons with raised crowns, particularly in those cases where the crown is to be supplied in the as-cast condition, we are experiencing Foundry difficulties owing to the fact that so far the raised portions have been specified with parallel sides. We are writing to ask if it would be possible for these raised crown portions to have sides with a 3° taper, and our preliminary suggestion is that this taper should intersect the present vertical side at the centre point so as not to alter the affective volume of the raised portion. In cases where the raised portion is high, say .470" for example, this procedure increases the width of the base of the raised portion by .012" per side, and we must therefore take care that the cylinder head clearance is sufficient at this point to allow of the modification. We attach herewith a sketch A.2291 illustrating the foregoing and we shall be glad to learn in due course whether the proposal is acceptable to you. Yours faithfully, FOR THE LIGHT PRODUCTION CO.LTD. A.H. Brooks GENERAL MANAGER. | ||