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).
Visit to the spring manufacturer Jonas Woodhead, covering their output and manufacturing processes.
| Identifier | ExFiles\Box 9\5\ 05-page148 | |
| Date | 22th December 1937 | |
| To By...... from Da{Bernard Day - Chassis Design}/DB.{Donald Bastow - Suspensions} c. Da.{Bernard Day - Chassis Design} Rm.{William Robotham - Chief Engineer} 646 Da{Bernard Day - Chassis Design}/DB.{Donald Bastow - Suspensions}12/N.22.12.37. Visit to Jonas Woodhead. WES After the reading of my paper in Leeds on Wednesday the 15th.inst. Mr T.H.Sanders, of Woodheads invited me to look round their Works on the following morning, and I accordingly spent a short time there. The making of motor car springs appears to be only a small part of their total output, in spite of the fact that they make all of Standard's springs (about 2000 a week) and some for Austin's, and Vauxhall's. They make the transverse springs for the independent front suspensions of Alvis and Humber-Hillman, all of which have solid forged eyes. Some of the Humber springs, probably those for the Snipe Imperial and Pullman, with an obviously higher static deflection, and hence larger number of thinner leaves, appeared to have all the leaves ground, I believe by hand. A lot of their output is springs for commercial vehicles and also for railways, and they are making all the wheel springs and the buffer and drawbar springs for the new Underground Railway rolling stock. Many of the Railway and commercial vehicle springs have the solid forged eye on the main leaf, and Mr Sanders commented upon the fact that we appeared to have dropped it, although it was used by commercial vehicle manufacturers, where cost was important, and also by Hillman's even on the 14 h.p. for the transverse front spring of the independent front suspension. Almost all their work is of the black-bar variety, and one of the interesting things seen was a machine giving a direct Brinell reading of the core material of spring leaves, through the scale and decarburised surface material. They appear to be installing some new equipment for heat treatment and bringing their Works more up-to-date in that respect. I was told that for normal work they use a scrag stress of 68 1/2 tons per square inch, and a normal stress for rear springs of one half of this, and for front springs of one third of this, going to rather higher figures for these normal stresses, if the static deflection is high, i.e. for soft springs where the ratio of maximum load to normal Cont'd.{John DeLooze - Company Secretary} | ||