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 considerations for a new die-cast chassis piston.
| Identifier | Morton\M11\ img087 | |
| Date | 26th October 1918 | |
| To WH. from E.{Mr Elliott - Chief Engineer} Copy to BY.{R.W. Bailey - Chief Engineer} " " DA.{Bernard Day - Chassis Design} " " EFC. ORIGINAL. 2. 26th October, 1918. E1/G261018N 1918 [STAMP: RECEIVED with clock face] X.3400 RE CHASSIS PISTON. We attach herewith confirmation of our telegram of even date, concerning the above, also the sketch referred to in the telegram. The piston shewn on the sketch is intended to be suitable for manufacture by die casting. The design is exceedingly plain and errs we think possibly in not providing sufficiently against distortion of the skirt. It should be tried however, in the form shewn, and we will afterwards add any further features that may be found necessary. The crown in the centre need not be very thick, because at this point no great heat flow occurs. The thickness however, should increase very rapidly towards the side of the piston. This particular design of crown has been found to give better results than those of the ribbed variety by the R.A.E. The heat flow from the crown is deflected round the corner into the metal behind the rings, a certain amount of heat is lost opposite the rings, and the inside may taper slightly. The piston wall then passes round the corner opposite the bottom ring, and from this position tapers from a thickness of .3" to a thickness of .150" at the base of the piston. Four pressure rings are fitted, the lowest of these (Contd.) | ||