Rolls-Royce Archives
         « Prev  Box Series  Next »        

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).
Cooler test results, comparing Ph.III and Buick models, and providing design conclusions.

Identifier  ExFiles\Box 131\1\  scan0161
Date  7th December 1935
  
-2-

Hs{Lord Ernest Hives - Chair}/Std.19/KW.7.12.35.

(7) No. 6 test was repeated, using the same matrix re-dipped with high temperature solder (as used for Glycol tanks), the matrix being first stripped and cleaned of course. Leakage occurred at 125 lbs/sq.in., oil temp. 130°C, at the junction of the outer ring of tubes and outer casing.

(8) All coolers which have burst in service (four in all) have leaked at the junction of the outer ring of tubes and the outer casing.

(9) Many of the coolers burst in service or during our tests have had bulged side and end casing plates, due to having insufficient strength to resist the internal pressure.

(10) The Buick cooler has withstood 200 lbs/sq.in. (oil cold) and 150 lbs/sq.in. (oil at 130°C.) without any leakage of visible distortion.

Conclusions.

Firstly, from the tests carried out it is obvious that the outer casing of the Ph.III cooler is not strong enough, while that of the Buick is strong enough. The difference we attribute to the corrugating of the end and side plates on the Buick cooler. Since the Ph.III cooler was developed directly from the Buick cooler, we suggest that their practice is adhered to throughout. We cannot settle the question as to the desirability of high temperature solder until we have an adequately strong outer casing, but we think that this may not prove necessary.

Secondly, the original type of matrix tube should be used, since (a) there is not real justification for the new type (b) we understand from the Makers (who have been in touch with the O.O.) that the new type tube is not a practicable manufacturing proposition.

Finally, we would point out that in spite of the Buick cooler's strength, the Buick system provides a pressure release valve which prevents the cooler being subjected to the maximum cold oil pressure. We suggest that this should certainly be incorporated in our design. We are aware that this impairs the warming up effect of the cooler to some extent.

[Handwritten in left margin]:
American
*
Subject to confirmation

Hs{Lord Ernest Hives - Chair}/C.S.Steadman.
  
  


Copyright Sustain 2025, All Rights Reserved.    whatever is rightly done, however humble, is noble
An unhandled error has occurred. Reload 🗙