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).
Specifications and calculations for springs used in a centre point radiator mounting.
| Identifier | ExFiles\Box 19\6\ Scan041 | |
| Date | 6th May 1930 | |
| For Files. x7518 X.7250 X.79600 X.7518. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} 6.5.30. CENTRE POINT RADIATOR MOUNTING: Springs actually fitted to 1-WJ and 80-WJ. No. of coils (Total) 7.5 Wire. 12 S.W.G. Mean rad. .292 Free length 1.350 Choc length .780 Rating 120,000 x .000117 / 6.5 x .0247 = 21 / .160 = 134 Lbs/1" Normal load = set up x rating. = .220 x 134 = 29.5 lbs. 7,700 lbs/sq.in. Max. load = choc a bloc = .570 x 134 = 76 lbs. = 20,000 lbs/sq.in. stress. Washers fitted to Hs.{Lord Ernest Hives - Chair}290. Rm.{William Robotham - Chief Engineer} | ||