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).
Letter to The Hoffmann Manufacturing Co. Ltd. discussing bearing design specifications and modifications.
| Identifier | ExFiles\Box 84\4\ scan0341 | |
| Date | 15th November 1937 | |
| c. DT. c. Rm.{William Robotham - Chief Engineer} c. Des. 202 15th. November 1937. Da{Bernard Day - Chassis Design}/Hdy.{William Hardy}6/E.{Mr Elliott - Chief Engineer} The Hoffmann Manufacturing Co. Ltd., Chelmsford. For the attention of Mr. C.H. Smith. Dear Sirs, We thank you for your letter of the 8th inst. (ref. CHS/AMB.102468A.), and for the prints of your drawings 41-477J Sections 83 and 84, and 43-661E Section 46 enclosed therein. We note that you have no object to the bore of the bearing to your drawing 41-477H Section 74 being increased to 1.812. We also note that you consider the double row roller a better means of increasing the capacity of the nose bearing than the use of a larger roller in a race of the same outside diameter. We are obliged to you for working out the two row bearings of the Phantom 11 type, and as we expected they are a good deal larger than we should care to accommodate on an axle of the size in question. Referring to the compound bearing to your drawing 41-477H. Section 74, we think it likely that we shall prefer to set the amount of preloading by a stop for the clamping nut external to the bearing rather than by clamping up the bearing races with no other stop than the races themselves. From recent experience with our standard bearings we think that the separate stop will be necessary to avoid distortion of the races which might occur if the races took the full force of the nut. Another reason for preferring the external stop is that by this means we avoid clamping the floating thrust races more than is necessary and they are therefore as free as possible to align themselves with the races on the pinion. If we adopt the above suggestion there will be, it appears to us, a material reduction of the cost of manufacture of the bearing, as there will now be no need for | ||