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 Ferodo Ltd. with observations and recommendations regarding procedures for their testing rig.
| Identifier | ExFiles\Box 141\2\ scan0277 | |
| Date | 29th March 1939 | |
| 1180 EXPERIMENTAL DEPARTMENT. Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems}6/JH. 29th.March, 1939. Messrs. Ferodo Ltd., Chapel-en-le-Frith. For the attention of Mr. Shilton. Dear Sirs, Following the visit which the writer payed you yesterday, we should like to make the following observations which we hope will be of some assistance and help in obtaining consistant and useful records from your testing rig. We agreed yesterday that it is essential to carry out tests on each lining separately starting with a clean plate and running in the material to surface the disc and as far as possible simulate conditions existing in service. The tests on the Thermoid confirmed this. A routine running in period should be established and this carried out on each material tested. We have endeavoured to analyse the /u speed curves taken and find that period of acceleration is variable for each curve and this makes two curves with the same /u speed characteristics not record similar curves on the record. Until such time as we are able to obtain consistent results we think it would be advisable to lengthen the record to enable us to plot the /u speed characteristic from the 1/10 second marks, and to make this possible we must insure that the drive is positive to give us the same travel for each revolution of the disc. The tendency at present would be for the drive to slip during the acceleration and deacceleration periods which are the points in which we are most interested. | ||