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).
Letter to Laystall Motor Engineering Works regarding the process and cost for fitting steel liners into drums.
| Identifier | ExFiles\Box 85\1\ scan0242 | |
| Date | 11th November 1936 | |
| Experimental Department 11th November 1936. Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale}8/AP. FTB/IP Messrs The Laystall Motor Engineering Works Ltd., Ewar Street, Southwark, LONDON S.E.1. Dear Sirs, We have decided to forward to you a pair of drums cases so that you can insert the steel liners, and we agree to pay you the sum of £1. 15. 0. for each liner, this price to include the fitting. Will you please carry out this work as follows:- Prepare the liners in carbon steel, check the Brinell of each (this should be between 300 and 350) and machine them accurately to our drawing. Heat the aluminium cases to 200 - 230°C, and drop the liners in. Please do not exceed 230°C, or you will weaken the aluminium, and this temperature should enable you to insert a liner that has distorted after machining. The liner's thickness should be about .150" when it is inserted (limits of thickness .125" and .175") The interference fit should be .025" to .030". As regards the liner sizes, we usually find the liners distort after machining, and so we check them on 3 or 4 diameters, and take the average. We should like to know in due course, what percentage of carbon you propose to use in the steel. As regards the price, the figure of £1. per liner appears to us to be extraordinarily high, as our present cast iron liners, cut from castings of a very expensive alloy iron cost about half the amount, so we intend to obtain a number of continued | ||