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).
The failure of Phantom III oil coolers, detailing the number of failures and types.
| Identifier | ExFiles\Box 131\1\ scan0287 | |
| Date | 17th August 1937 | |
| To Hs.{Lord Ernest Hives - Chair} c. to RHC.{R. H. Coverley - Production Engineer} c. to Hd.{Mr Hayward/Mr Huddy} c. to Mx.{John H Maddocks - Chief Proving Officer} 1114 Failure of Phantom III Oil Coolers. In connection with the above we have established the following facts :- (1) Total number of failures in service - 12 - chassis 3-AZ-88, 3-AZ-98, 3-AZ-102, 3-AZ-104, 3-AX-9 3-AX-81, 3-AX-238, 3-BU-116, 3-BU-146, 3-BU-62. Chassis 3-AZ-104 & 3-AX-81 have had two failures each. (2) All failures have been on oil coolers of the type prior to Jan. 18th. 1937 i.e. with case hard soldered to matrix. Since this dat all coolers have been made by dip soldering. (3) The total number of hand soldered oil coolers which have been put in service is approx. 360 - the percentage of failure therefore being 3.3 (4) The total number of dip soldered oil coolers at present in service is approx. 50, failures nil. (5) The works have kept no record of what number cooler is fitted to any given power unit or chassis - it is impossible therefore to say definitely in what chassis the 360 hand soldered coolers are fitted - there will definitely be approx 185 fitted on A series and the majority of the remainder will be in B series, but a few will be fitted on C series. (6) Examination and sectioning of three of the defective coolers has indicated that the hand soldering was defective at the points where the leaks occurred, the depth of solder in one case being only 1/16" instead of the correct 5/16". (7) Attempts to fail two of the latest type of oil cooler by alternating the pressure from 0 to 200 lbs.sq.in have so far failed ( 500 pressure changes made to date in each case. | ||