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 comparative strength testing of new dip soldered type oil coolers versus old type coolers.
| Identifier | ExFiles\Box 131\1\ scan0319 | |
| Date | 7th September 1937 | |
| -2- Since issuing our last report on this subject, in which we mentioned that we had tested two new type coolers by subjecting them to alternate pressures of 0 and 200 lbs/sq.in. 500 times without failure, we have tested two old type coolers in similar manner and these failed after 39 and 91 pressure changes respectively. We are fitting the two new type coolers tested to experimental chassis to see whether any trouble is experienced in service. CONCLUSIONS (1) No failure of the new type cooler - dip soldered type- has yet been notified to us (Nos. E.386 onwards) - our tests have established that its strength is definitely superior to the old type. (2) When a new cooler is fitted in future after a failure, the water system should be thoroughly cleaned out in the manner described on attached sheet, so that oil coolers are not changed unnecessarily. (3) If an oil cooler leakage is suspected on a chassis it should be tested for, before removing the oil cooler - this could also be done with advantage on customers' cars which are going abroad for touring etc. so that the chances of failure are minimised. The method of testing is to make a connection to the cooler (having removed existing pipes) with an air pressure line and a pressure gauge - raise the pressure to 200 lbs/ sq.in and shut off air - the pressure should remain at this figure for say 15 minutes without dropping. N. have a rough apparatus for this test which we rigged up while down there- we are having some better equipment made up here and will forward it together with instructions to N. and Paris. (4) We are carrying out tests with a view to dispensing altogether with the oil cooler on Ph.III. and the next car (39-EX) in France will have no oil cooler fitted. If we find that this is practicable, we think that we should consider removing oil coolers from all Ph.III. cars. SUMMARY (1) No failures have yet been experienced on latest dip soldered type coolers. (2) We think more running experience on this new cooler is necessary before any step such as changing all old type coolers for latest type is taken. continued | ||