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).
Advantages of using separate cylinder liners over the existing solid cast design.
Identifier | ExFiles\Box 132\4\ scan0032 | |
Date | 25th November 1936 | |
To Rm.{William Robotham - Chief Engineer} From RHC.{R. H. Coverley - Production Engineer} c. to Sg.{Arthur F. Sidgreaves - MD} c. to Hs.{Lord Ernest Hives - Chair} c. to E.{Mr Elliott - Chief Engineer} c. to Dy.{F R Danby} 1124 RHC.{R. H. Coverley - Production Engineer}1/MJ.25.11.36. CYLINDER LINERS. Replying to Rm.{William Robotham - Chief Engineer}2/AP.23.11.36 it is suggested the time has arrived to give very serious consideration to cylinder construction in view of the amount of casting scrap involved with the present design, which is accentuated by difficult and expensive machining operations around the trunks which exist where liners are solid with the casting. There is also the difficulty of producing accurately ground bores, the only satisfactory method being to rotate the work, which is impossible with the existing construction. The present block demands honing which is, in principle, an unsatisfactory process because the hone emerges from the cylinder at the end of each stroke and a barrel-shaped bore results. Again, owing to the tendency for honing to follow rather than rectify existing inaccuracies it is never certain that bores will be truly parallel and in alignment with each other. The introduction of separate liners would permit of rotating the work, which affords the only satisfactory means of grinding a parallel and concentric bore with a finish which will eliminate wear. There would also be a saving on machining time due to the elimination of difficult machining operations around the trunks, referred to previously, and this construction would make it possible in addition to combat wear by taking advantage of special cylinder materials, the employment of which is impracticable whilst the cast iron block is retained. In addition the casting will be simplified which will tend to eliminate foundry difficulties and scrap. RHC.{R. H. Coverley - Production Engineer} [Signature] LWH. Will you please return. | ||