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 Rudge-Whitworth, Ltd. concerning the performance and heat treatment of piston rings.
| Identifier | ExFiles\Box 148\3\ scan0113 | |
| Date | 3rd December 1935 guessed | |
| EEAC. 7/86. Continued Letter to Messrs. Rolls Royce Ltd., Derby. Rudge-Whitworth, Ltd. Sheet No. 2. We have found that the use of such rings in an unhardened cylinder reduces the rate of cylinder wear by at least 25%. There is also a reduction in the rate of wear of the rings, both in the vertical direction and on width, but these figures are too variable to quote from. The Manufacturers claim a reduction in the rate of wear on width of 50%, and they also say that when hardened rings are run with hardened cylinders, the combined wear is reduced 100%, compared with soft rings and cylinders. Exact particulars of the heat treatment are not available, but the rings are oil quenched, and subsequently tempered, probably in the region of 400°C. When we first tested these rings it was found that the free gap of the top ring closed right up after severe work on the bench. This fault was subsequently corrected by raising the tempering temperature, and now no trouble with the closing of the free gap is experienced. Yours faithfully, For RUDGE-WHITWORTH LIMITED. y. l. HaefpMH. Tech. Development Dept: | ||