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 from the Vacuum Oil Company discussing oil viscosities at various temperatures.
| Identifier | ExFiles\Box 145\1\ scan0053 | |
| Date | 30th November 1933 | |
| X1588. WE DO NOT HOLD OURSELVES RESPONSIBLE FOR LOSSES OR DAMAGE RESULTING FROM DELAY IN FILLING ORDERS CAUSED BY STORM, STRIKES, FIRE, DIFFERENCES WITH WORKMEN OR ANY CAUSE BEYOND OUR CONTROL; VACUUM OIL COMPANY. LIMITED MANUFACTURERS AND MARKETERS OF HIGH GRADE LUBRICATING OILS AND GREASES SOLE MARKETERS OF Mobiloil-THE WORLD'S QUALITY MOTOR OIL AUTOMOTIVE LUBRICANTS DEPARTMENT. TELEGRAPHIC ADDRESS VACUUM, PHONE, LONDON. TELEPHONE WHITEHALL 1010 (14 LINES) WHEN TELEPHONING PLEASE ASK FOR EXTENSION N° GARGOYLE REGD TRADE MARK. MANUFACTURING PLANTS. WANDSWORTH, LONDON. WEST FLOAT, BIRKENHEAD. BRANCH OFFICES BELFAST SCOTTISH PROVIDENT BUILDINGS. TELEGRAMS VACUUM BIRMINGHAM 6, CAROLINE STREET. TELEGRAMS VACUUM PAN BRISTOL 58, QUEEN'S ROAD, CLIFTON. TELEGRAMS GARGOYLE PHONE CARDIFF DOMINIONS HOUSE, QUEEN STREET. TELEGRAMS VACUUM DUBLIN 32, NASSAU STREET. TELEGRAMS VACUUM GLASGOW 400 E.{Mr Elliott - Chief Engineer} CATHEDRAL STREET. TELEGRAMS VACUUM PAN HULL 27, SCALE LANE. TELEGRAMS VACUUM LIVERPOOL CUNARD BUILDING. TELEGRAMS VACUUM MANCHESTER 196, DEANSGATE. TELEGRAMS VACUUM NEWCASTLE-ON-TYNE COMMERCIAL UNION BUILDINGS, PILGRIM STREET, TELEGRAMS VACUUM SHEFFIELD QUEEN'S BUILDINGS. QUEEN STREET. TELEGRAMS VACUUM UNLESS STATED OTHERWISE, ALL OILS ARE QUOTED AND INVOICED PER UNIT GALLON OF 9-LBS. ALL QUOTATIONS ARE WITHOUT ENGAGEMENT UNLESS STATED OTHERWISE. CAXTON HOUSE, WESTMINSTER, IN REPLY PLEASE REFER TO B1/Eng LONDON, S.W.1. 30th November 1933. Messrs. Rolls-Royce Ltd., Derby. Re:- Oil Viscosities. Dear Sirs, In reply to your letter of the 25th instant, reference Hs{Lord Ernest Hives - Chair}/Lid.{A. J. Lidsey}5/KT, and further to ours of the 27th instant, we have pleasure in attaching a table showing the viscosity readings of Mobiloil D, together with various other engine oils. We have included viscosities at 100°F and 200°F which will enable you to make comparisons with Air Ministry Specification D.T.D.109 and oils of similar class, and also viscosities at 23°F (-5°C). With regard to the latter it is not practicable to measure accurately viscosities at temperatures as low as this with ordinary instruments, and we doubt whether anybody in this country has the necessary apparatus, with the possible exception of the National Physical Laboratory. We believe, however, that the figures quoted are sufficiently close to give a useful comparison between the different oils, but it is of course, important to remember that at temperatures approaching the pour point of the oil there will be considerable deviations from any plotted curve. With regard to the figures given for oils other than Mobiloil grades, these are, of course, approximate only, though we believe they are representative. You will note that in addition to Mobiloil D we have included Mobiloil AF, which is the grade of oil we suggest should be used in the 3½ Litre Bentley engine where atmospheric temperatures are normally between 32°F and 20°F in order to ensure reasonable ease of starting from cold and immediate circulation. In countries where temperatures below 20°F are experienced it is the usual practice to use an oil with characteristics like Mobiloil Arctic, which is also shown, on account of the difficulty of starting from cold with heavier (Cont'd) | ||