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).
Clearances and fitting for Bentley main and connecting rod bearings.
| Identifier | ExFiles\Box 115\3\ scan0079 | |
| Date | 29th October 1937 | |
| RM{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}8/MH.{M. Huckerby}29.10.37. BENTLEY BEARINGS. Herewith clearances and fitting of Aluminium Tin bearings on Bentley in accordance with up-to-date recommendations. (1) MAIN BEARINGS A.C.2. (a) "Nip". The "nip" is the amount the bearing halves stand proud of the joint face. This should be .001 at each side of the bearing relative to the joint face and on both halves. Before the bearing is clamped up, therefore, there is .002 clearance on each side. (b) "Interference fit". Interference fit is the amount that the outside diameter of the bearing is in excess of the diameter of the housing into which it fits. This should be to normal dimension .001 and with extreme limits giving size and size. (c) Working Clearance. Diametrical clearance between the crankshaft journal and the bore of the bearings. This should be to normal dimensions .003 and with extreme limits, a minimum of .00275 and maximum of .0035. (2) CONNECTING ROD BEARINGS (A.C.7) (a) "Nip". This to be precisely as for main bearings. (b) "Interference Fit". This to be precisely as for main bearings. | ||