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).
Development report on the Peregrine power unit, detailing issues with mechanical reliability, lubrication, and the crankshaft damper.
| Identifier | ExFiles\Box 179b\2\ img106 | |
| Date | 14th November 1938 | |
| M.{Mr Moon / Mr Moore} From HS{Lord Ernest Hives - Chair}/Ms. c. to Sg.{Arthur F. Sidgreaves - MD} c. to WsP. c. to H.{Arthur M. Hanbury - Head Complaints} c. to A.{Mr Adams} c. to Sy. c. to De. c. to RdY. X407 Hs{Lord Ernest Hives - Chair}/Ra.S/MA.14.11.38. PEREGRINE POWER UNIT DEVELOPMENT. We have now run many hours on the test bed with Peregrine units. Mechanical Reliability. The only mechanical failure of any sort has been one exhaust valve which broke off right in the neck. We attach a photograph. As we have had occasional failures of this kind on our other units, 45HP & 41/50 no alteration has been made pending further failures of the same kind. We had one or two cylinder studs strip when changing heads. Increasing the dia. has improved the situation. Lubrication. The main distribution of the crankcase oil and the filling passages have all been made satisfactory by H's modified schemes. We have not as yet succeeded in getting the extra c.l. lubrication to function satisfactorily automatically. If it does not cut off at 350°C. we oil up plugs. We cannot get a thermostat of the size that can be got in, to operate at this temperature. We are continuing experiments. Crankshaft Damper. With the 2.250" journal crankshafts, the trouble with the crankshaft damper "clattering" at high speeds has been greatly improved. We have established that the speed at which this occurs is directly related to the critical shaft speed. With the 2.00" journals the damper became audible at about 4500 R.P.M. With the 2.250" journals not until over 5000 R.P.M. | ||