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).
Test report on an internally chromium-plated cylinder liner, detailing failure analysis, wear, and previous experience.
| Identifier | ExFiles\Box 127\3\ scan0115 | |
| Date | 8th October 1936 | |
| Hs{Lord Ernest Hives - Chair}/Wd.{Mr Wood/Mr Whitehead}7/WJ.8.10.36. INTERNALLY CHROMIUM PLATED LINER USED ON THE UNIVERSAL SINGLE CYLINDER UNIT. A cylinder liner E.47264, chromium plated in the bore, has been run for 153 hours water cooled, at the end of which time failure occurred through cracking at the top flange. RESULT OF TEST. The wear at the top of the liner was .002 - .0025 which is practically the same as that occurring with an unplated liner. There were a number of score marks in the chromium. The adhesion of the chromium to the steel is poor, as revealed by photomicrograph A.1500. The flakes of chromium appear to be curling up at their edges. No trouble with seizing was experienced on the Universal unit. Previous experience with chromium plate. A chromium plated liner had been run previously on the Kestrel Single Cylinder unit glycol cooled under "take-off" conditions for 53 hours. During running partial seizure occurred three times and the piston skirt was relieved a little each time. On examination after these seizures traces of chromium appeared on the piston but no piston metal had picked up on the cylinder bore. The maximum wear was .0025 which is not good, but the piston ring wear was very small (see report Hs{Lord Ernest Hives - Chair}/Wd.{Mr Wood/Mr Whitehead}1/GB.4.5.36). Note on failure of liner. Complete failure of this liner occurred through cracking at the top flange, as mentioned previously. The external nickel plate had been machined away in the small radius beneath the top flange, permitting the steel beneath to be attacked by the coolant and so causing failure of the liner (see Laboratory report). It is suggested that external plating should in future be carried right round the radius and at least to the outside edge of the flange. | ||