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 Ferodo Limited concerning the composition of oil in clutch discs and the performance of servo linings.
| Identifier | ExFiles\Box 141\3\ scan0210 | |
| Date | 5th September 1933 | |
| X719 All Communications to be addressed to the Company. FERODO LIMITED TELEPHONE: 19 CHAPEL-EN-LE-FRITH (4 LINES) TELEGRAMS: FRICTION, PHONE, CHAPEL-EN-LE-FRITH. FERODO BRAKE & CLUTCH LININGS CHAPEL-EN-LE-FRITH, VIA STOCKPORT, ENGLAND. CODES: WESTERN UNION FIVE LETTER EDITION, BENTLEY'S COMPLETE & 2ND PHRASE, MARCONI INTERNATIONAL, LIEBER'S CODE, LIEBERS LATEST CODE, A.B.C. 5TH & 6TH EDITIONS. Depots:- LONDON 222, TOTTENHAM COURT RD W. 1. ABERDEEN 26, GUILD STREET. BELFAST 8, 10 & 12, MONTGOMERY ST BIRMINGHAM 202, CORPORATION ST BRIGHTON 84, QUEEN'S ROAD. BRISTOL 19, PARK STREET. CARDIFF 39, CHARLES ST.{Capt. P. R. Strong} DUBLIN 120, UPPER ABBEY ST GLASGOW 70, WATERLOO ST LEEDS 25, HUNSLET RD LIVERPOOL 1-3, BERRY STREET. MANCHESTER 32, CATHEDRAL ST NEWCASTLE-ON-TYNE WORSWICK CHAMBERS, 10, WORSWICK ST OFF PILGRIM ST September 5th 1933 YOUR REF. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}2/KT. OUR REF. FJF/WAC. Messrs. Rolls Royce Limited, Derby. For the attention of Mr. Grylls. Dear Sirs, We are obliged by the information given in your letter of the 1st instant. Referring to the composition of the oil extracted from your clutch discs, we suggest that of the balance of 35% the quantity of Tung Oil could at most hardly exceed 1% as the quantity of that oil used in the impregnation is very small indeed, and apart from this, it is polymerised at 500°F.{Mr Friese} However, the main point rests with the presence of the lubricating oil - as you suggest, oil vapour may be considered to be responsible in the absence of direct evidence of "creep" but the writer feels that oil vapour alone is not entirely responsible in view of the fact that the great majority of clutch parts are subjected to conditions approximating to those in your clutch without a trace of lubrication on the friction surfaces. We do not know of any other lining that is not affected by oil or any which are not oil-absorbent to some extent - certainly RAD.13 is not more affected than any other type, therefore we cannot suggest an alternative material that would be more suitable under the conditions which obtain as in the case of the two clutches from which the oil-penetrated lining was taken. We note your remarks in connection with the performance of FF. 239 servo linings and are sending a further pair - the balance of 10 will reach you to-morrow morning. These - as you will no doubt appreciate - have been die made and have double selvedge edges, a method of construction which we think will be more satisfactory for floating discs than cut-out discs, which have a tendency to fray at the edges. Yours faithfully, FERODO LIMITED, [Signature] CHIEF ENGINEER. | ||