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 plate clutch linings, discussing potential 'jaggering' issues.
| Identifier | ExFiles\Box 26\4\ Scan128 | |
| Date | 27th August 1921 | |
| R R 236A (100 T) (S H.{Arthur M. Hanbury - Head Complaints} 159, 11-8-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2800 COPY OF LETTER FROM:- MESSRS. FERODO LIMITED, SOVEREIGN MILLS, CHAPEL-EN-LE-FRITH. SALES DEPT. FJF/DHL. 27th August, 1921. (Friday) Messrs. Rolls-Royce Ltd., Nightingale Road, D E R B Y. Dear Sirs, re:- PLATE CLUTCH LININGS, G-50213. (Ref:- Wd{Mr Wood/Mr Whitehead}/Dn3/HP.24821). We duly received your letter of the 24th inst. In regard to the question of the resultant action of our FEROBESTOS Plate Clutch Discs picking up the load smoothly, in our view no differences will arise between the action of material with or without graphite, since the effect of the dry lubricant is to reduce the friction value, which must be compensated for by increased pressure. Therefore, in our opinion, similar conditions are established. If non-impregnated linings jagger, equally so should those with graphite. We cannot at the present time, test clutch linings, our test plant being in course of reconstruction, the clutch plate portion is not ready. In any case, we could not indicate the condition you mention, as such is impossible to produce on a machine of substantial construction and perfect alignment and balance. Jaggering invariably arises as doubtless you are well aware, from a number of contributing causes, such as a light flywheel, springing shafts, error in alignment, distortion and lack of rigidity in the metal driven disc. We are inclined to the opinion that your clutch design G-50210 will be liable in some degree to jagger - the driven disc is very thin and supported on a bolt circle of small diameter. All single plate clutches employing substantial metal driven plates are invariably satisfactory with or without a clutch stop, when the energy stored in the flywheel is sufficient | ||