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).
Supply, manufacturing methods, and revised steel specifications for Merlin cylinder liners.

Identifier  ExFiles\Box 132\5\  scan0143
Date  25th June 1940
  
1123

Rm.{William Robotham - Chief Engineer}
c. Hs.{Lord Ernest Hives - Chair}

Cgh{W Clough}/EM.7/MM.25.6.40.

Cylinder Liners.

Confirming our conversation of a few days ago, we attach hereto 3 prints of the makers drawing of our Merlin Cylinder Liner Forging part number D.7596.T1.

We are not happy in regard to supplies in this country and with the agreement of Hs.{Lord Ernest Hives - Chair} it is suggested that enquiries are made and quotations obtained from U.S.A. for 1000 sets of these parts.

We would naturally prefer that such liners are made by our present method if possible.

The liners we are using are at present made from hot rolled tube, which is cut length and the collar forged up on our "Ajax" forging machine. Should this method not be available there is no objection to the Liner being produced in a shell press, in which case it would of course be pierced and raised in one operation from a solid billet of material.

The actual Liner is specially heat-treated to give a very high Brinell viz 360/400, and this of course involves same care in the selection of a suitable analysis of steel for the purpose.

The steel specified on our drawings is R.R. Spec. 2052 of which we believe you have a copy, but recently we have found that the addition of Chromium is beneficial and we are now instructing our English suppliers to work to the following chemical composition which we find eases the heat-treatment problem considerably :-

Carbon 0.58 to 0.70%
Manganese 0.55 to 0.75%
Silicon not more than 0.30%
Sulphur " " " 0.05%
Phosphorous " " " 0.05%
Chromium 0.60 to 0.75%

The Liners are rough turned and bored before heat-treatment to a general wall thickness of 3/8" and in this section should give after suitable hardening and tempering a Brinell of 360/400.

Continued Overleaf.....
  
  


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