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).
Drip plug specifications, lubrication system rearrangements, and front axle feed improvements.
| Identifier | ExFiles\Box 26\5\ Scan026 | |
| Date | 14th April 1927 | |
| Oy1-E-41427 -2- April 14, 1927 (2) A "Banjo" type drip plug (see sketch) is necessary to complete the scheme and Bijur has promised to give us these. (3) For lubrication of such small parts as generator bearings etc. Bijur has given us a "fractional type" drip plug with about 1/5th of the delivery of a No.1 type plug. (4) Drip plugs. Standard sizes are as follows:- No. Hole Dia. Pin dia. Approx.C.C.per min. Approx. drops per min. Engine oil at room temperature 00 (frac- .063 - ? .03 .6 tional) 1 .063 .061 .15 3. 2 .063 .060 .25 5. 3 .063 .059 .40 8. 4 .063 .058 .63 12. 5 .063 .057 1.00 20. 6 .063 .056 1.50 30. The number of drops "per shot" which for any design is approximately constant and independent of temperature, cannot be stated apart from the system as a whole, since it depends on the total of the orifices in the system. (5) A rearrangement of the system (suggested by Mr. Haldenby) is in hand, which will as far as possible take all drip-plug connections as individual branches off a common "main" (which may be 5/16" or 1/4" pipe for the sake of strength.) Thus if any one of the small pipes breake and has to be pinched up only one fitting is put out of action. (We have never had a broken pipe except a few split in bending during assembly.) We have discussed this with Bijur who agrees in principle but objected to the consequent increase in the number of pipe joints. On our explaining our preference for the"banjo-type" fitting, Bijur agreed that the proposed revision was good. (6) Improvements in the feed to the front axle and side steering tube are being made, using for the axle feed a torsion-spring coil on the inside of the left rear shackle bolt, where it is clear of the exhaust pipes. The feed to the side steering tubes is no neater than the present scheme but causes lower stresses in the coils. It is sheltered behind the well in the left mudguard in | ||