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).
Design and manufacturing tolerances for 'SS' rear hydraulic dampers to allow for load adjustment.
| Identifier | ExFiles\Box 55\4\ Scan352 | |
| Date | 12th April 1929 | |
| Y235 To BY.{R.W. Bailey - Chief Engineer} To DA.{Bernard Day - Chassis Design} }} From Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. to Wor.{Arthur Wormald - General Works Manager} Hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}3/LG12. 4. 29. 'SS{S. Smith}' HYDRAULIC DAMPERS. REAR : Provision for load adjustment. +7520 We have now built up a number of sets of these dampers. As in the case of the front hydraulic dampers, the valves have been brought outside to facilitate the adjustment of the damper loads by Depots. We wish Depots to be able to set the damper loading by washers under the valve caps as previously specified for the front dampers. In order that any given washer, when fitted under the valve cap, may give a fixed load, it is essential that in every case the spring length d.{John DeLooze - Company Secretary} should be fixed accurately when the damper leaves the Works with a washer .020" thick at W. For this to be possible, the valve, valve cap, spring free length and valve seat dimensions will all have to be held within close limits. At the present moment on F.79384 the dimension D.{John DeLooze - Company Secretary} has a limit of +10. Will you please bring this into line with the corresponding dimension on F.80321 for the front damper and give it a ± 2 limit. Also we think that on the valve caps the dimension F.{Mr Friese} might be held on all caps to +2 as shewn on F.79818. We presume the spring free lengths on such a small spring could be held to ± 3. We think that, as in the case of the front damper, a single valve can be used for both high and low pressure contd :- | ||