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).
Spring deflection and the theory versus practice of chassis lubrication via drip-plugs.
| Identifier | ExFiles\Box 27\1\ Scan252 | |
| Date | 30th July 1934 guessed | |
| -3- We do not agree with the suggestion that the spring practicaly becomes choc-a-bloc and have demon- strated this to the Works. There are 20 coils in the spring of wire dia. .176, giving a choc-a-bloc figure of 3.52". The max. deflection of the spring never compresses it to more than 4.500", so there should be a gross clearance of practically 1.000 under the worst conditions. The fact that one side of the chassis supplies more units than the other makes a very small difference indeed to the amount of oil each side receives. This one would expect from the fundamental analogy to the electrical circuit, the pump being the generator of pressure. The flow is so small all over the chassis that the difference of pressure at various points is not within the limits of error of a standard pressure gauge. Hence each drip-plug of the same kind should and does deliver the same amount. We were ourselves surprised that in practice this theory was so absolutely maintained. Theoretically, the actual amount that SO, S1 and S2 drip-plugs should give is 5 to 7, 15 to 17, and 30 drops per shot. Actually we got 6, 15 and 32 from the shock damperslever, the equaliser shaft, and the rear spring shackles. The Test Dept., (Daykin) will confirm this, and also demonstrate that the off-side and near-side receive an exactly tha same amount. We agree that the sizes of drip-plugs in the neighbourhood of the engine, have had to be chosen in regard to | ||