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 from Leyland Motors discussing chromium bore wear on an aluminium cylinder block.
| Identifier | ExFiles\Box 140\4\ scan0252 | |
| Date | 28th February 1940 | |
| 1175 BY APPOINTMENT TO THE LATE KING GEORGE V.{VIENNA} LEYLAND MOTORS LIMITED, Head Office and Works, Leyland Manufacturers of Motor Vehicles. YOURS Rm{William Robotham - Chief Engineer}/1.M.L. IN REPLY PLEASE QUOTE: OURS CE/VWP/HK.{Col. T. Harker - Sales} Tel: Ext: 97. ALL COMMUNICATIONS TO BE ADDRESSED TO THE COMPANY AND NOT TO INDIVIDUALS CUSTOMERS' VEHICLES DRIVEN AT OWNERS RISK ONLY . . . TELEGRAPHIC ADDRESS: LEYMOTORS, LEYLAND. TELEPHONE: LEYLAND 81400 (16 LINES) LEYLAND. LANCASHIRE. 28th February, 1940. Dict. 26th. W. A.{Mr Adams} Robotham Esq., Rolls-Royce Ltd., DERBY. Dear Robotham, I have your letter of the 23rd, in which you advise me that the aluminium cylinder block has not yet come to hand; I cannot understand this, as it was despatched some considerable time ago. I can only assume that it is delay on the railways which has caused its non-arrival. You say you are somewhat puzzled by my reference to wear on the chromium bore of .002" to .003". I must point out that we use the term "Wear" somewhat loosely in talking about this problem, and it is generally meant to represent diametral wear, that is, nominal size, plus the wear stated. In that case you will see that the radial wear would only be in the order of .0015", and on the basis of 200,000 miles of operation the rate of wear of the chromium would be in the order of 130,000 miles per .001", which you will agree is exceedingly good. In any case, we have never attempted to 'flash' the bores as is indicated in your letter, and what we have attempted to do is to get a rate of wear guaranteed in the order of .001" for 30,000 miles and say two or perhaps three re-grinds. The nominal thickness of chromium which we wanted was between .005" and .006". I do not think it would be possible for us to arrange to have the cylinder block referred to in my last letter available for inspection by one of your assistants, as this is in the service of an operator somewhat removed from us at Leyland, and we have to rely on getting this information when our Service Test cards indicate that the vehicle is in for overhaul. | ||