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 to Borg & Beck Co. Ltd. regarding a discrepancy in Long C.F. Clutch specifications.
| Identifier | ExFiles\Box 130\3\ scan0040 | |
| Date | 23th December 1938 | |
| 1110 EXPERIMENTAL DEPARTMENT. Rm{William Robotham - Chief Engineer}/NRC.{N. R. Chandler}10/JH. 23rd. December, 1938. Messrs. Borg & Beck Co.Ltd., Tachbrook Road, Leamington Spa. re Long C.F. Clutches. Dear Sirs, On comparing the specifications BB.460 (10") and BB.471 (11") we note what appears to be a discrepancy in the release bearing pressures quoted, since the 10" with 125 - 135 lbs. springs is given as 225 lbs. and the 11" with 110 - 120 lb. springs as 250 lbs, and both have a finger ratio of 4.73. If we assume approx. .070 separation and that the orange and blue springs have a rate of (about) 160 and 141 lbs. respectively, we think the withdrawn pressures would be, in round figures, 270 lbs. for the 10" and 235 for the 11", and would be glad to know if you agree with these figures. We realize of course, that considerable tollerance must be allowed in figures of this sort, but the figures quoted on the specification appear to be reversed! Yours faithfully, FOR ROLLS-ROYCE LTD. | ||