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).
Ongoing issues and potential solutions for hydraulic damper gland leaks.
| Identifier | ExFiles\Box 5a\3\ 03-page258 | |
| Date | 28th May 1933 | |
| XX140 Hotel de France. Chateauroux. Indre. To Hs{Lord Ernest Hives - Chair} From G.W.H. 28.5.33. 18.3.IV. We have received your memo Hs{Lord Ernest Hives - Chair}7/MJ 26.5.33. RE HYDRAULIC DAMPER GLAND LEAKS. With the design of gland packing that we came out with, the oil leaks have been consistent. We gave them time to settle down, and the oil level was lowered, but they still leaked. We then dismantled the four dampers and made fresh asbestos packings impregnated them with tallow. We received word that packings were being sent out impregnated with tallow, therefore we fitted those as soon as they arrived. Our own packings had just about ceased to leak after loosing 20 cc. The new packings sent out did not give as good results as the ones we made until considerable mileage had been run, confirming my opinion that they are compressed too hard in the first place. The front dampers have allmost ceased to leak after 3200 miles, the loss of oil being 10 cc. from the top of the filler plug. The N.S. rear damper had lost 40 cc. in the same period, the O.S.R. double this amount. We therefore came to the conclusion that the design was wrong and we set about to improve it. I believe I am right in saying that a pressure of between 2 and 4 lbs is built up in the damper therefore to stop the glands leaking it was obvious that this pressure should be balanced either side the bearing if possible. A scheme was got out to obtain this, also a wedge shaped gland packing was made. This scheme gave definate better results right away, only a slight weep of oil taking place. Scheme (1) The scheme however was too cramped and we had not sufficient aera of packing on the outside dia. Scheme (2) was evolved. Not a sign of oil had leaked out for the 250 miles. Unfortunately the accident occured during this trip, and our test is stopped. It does however appear to have solved the leak question. In the first place we have got an equal pressure on either side of the bearing, and we dont mind oil floating through, after that we have got a really solid wedged shaped packing that can be put in the gland without being disturbed, or chances taken whilst fitting up. We shall be very interested to see what Bell is bringing out that can improve upon our own scheme. | ||