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 regarding brake lining tests, coefficients of friction, and an order for brake and clutch discs.
| Identifier | ExFiles\Box 141\3\ scan0270 | |
| Date | 9th June 1934 | |
| All Communications to be addressed to the Company. V719 FERODO LIMITED BRAKE & CLUTCH LININGS TELEPHONE: 19 CHAPEL-EN-LE-FRITH (4 LINES) TELEGRAMS: FRICTION, PHONE, CHAPEL-EN-LE-FRITH. CODES: WESTERN UNION FIVE LETTER EDITION, BENTLEY'S COMPLETE & 2ND PHRASE, MARCONI INTERNATIONAL, LIEBER'S CODE, LIEBER'S LATEST CODE, A.B.C. 5TH & 6TH EDITIONS. CHAPEL-EN-LE-FRITH, VIA STOCKPORT, ENGLAND. June 9th 1934 YOUR REF. OUR REF. FJF/WAC. Depots:- LONDON 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 DUBLIN 120, UPPER ABBEY ST GLASGOW 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 Messrs. Rolls-Royce Ltd., DERBY. For the attention of Mr. Grylls. Dear Sirs, Referring to Mr. Grylls' conversation with the writer yesterday afternoon, we have pleasure in enclosing a copy of our Diagram No. 149 giving coefficients of friction at different temperatures of various types of brake lining against a 14" solid Nitralloy drum of heavy section. Test conditions were - speed of drum 240 r.p.m. pressure constant 65 lbs per square inch. In general, the coefficients of friction of all materials are substantially higher than are given against steel and cast iron, particularly at the end of the continuous tests where temperature ruled between 600° and 620° F.{Mr Friese} These tests were run as far back as October 1931 and might be repeated perhaps with advantage with one of your Nitralloy drums. Referring to your instructions in respect to brake lining and clutch discs, we have entered orders as under:- 12 RAD.11 discs Part No. G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 56662 12 VM/20 discs Part No. G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 56662 6 sets of brake liners FB 4A comprising - 48 pieces G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 100789 drilled jig 561 24 " G.B. 750 " " 564 24 " G.B. 751 " " 563 24 " G.B. 752 " " 560 24 " G.B. 754 " " 562 We confirm that we have no information of particular interest to communicate in respect to discs for your servo motor, but we are continually experimenting in that direction. Unfortunately, we do not appear to be able to produce squealing under our test conditions, hence discs that we consider absolutely satisfactory appear to create objectionable noise when fitted to your cars. | ||