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).
Article on metallic coatings for piston rings, with excerpts from various automotive trade journals.
| Identifier | ExFiles\Box 142\2\ scan0428 | |
| Date | 15th April 1939 | |
| 492 1200. THE CHILTON ROUND TABLE In order to give readers of AUTOMOTIVE INDUSTRIES a clue to certain merchandising and service aspects of the automotive industry which are normally outside the scope of an industrial publication, we present herewith excerpts from the April issues of the four other magazines published by the Automotive Division of the Chilton Co. FROM AUTOMOBILE TRADE JOURNAL Dun & Bradstreet’s preliminary report of retail sales in sixteen trades showed some loss in sales for all trades in 1938 compared with 1937. Individual results varied widely and sales for motor vehicle dealers reporting showed a decline of 25 per cent in 1938 over the previous year. Small comfort in this, for dealers suffered greater sales loss than any of the other fifteen retail trades reporting. Since gasoline consumption in gallons held even with 1937, it seems likely that service once again was the real source of dealer profits. FROM COMMERCIAL CAR JOURNAL Germany has solved the problem of truck rating in characteristic totalitarian fashion. Beginning Jan. 1, 1940, the existing 15 load ratings for motor trucks will be liquidated as was Czecho-Slovakia and registering authorities will recognize only four. The only ratings that will be recognized for registration will be 1½, 3, 4½ and 6½ tons. The so-called commercial type will be allowed only in one type. We cannot help remarking how this differs from current thinking here. In the United States both those who use the trucks and those who sell them agree that maximum economy can be attained only by fitting the truck to the job, and that means an indefinite number of fits because of the variety of jobs to be performed. FROM MOTOR WORLD WHOLESALE One of the most popular regular monthly features of Motor World Wholesale is the list of 20 most active jobbing lines carried on the (Turn to page 507, please) By JOSEPH GESCHELIN PIONEER work of leading piston ring manufacturers has brought to light an interesting technique for reducing wear in parts subject to severe scuffing and abrasion during the initial break-in period. Paralleling this development is the use of somewhat similar treatment to provide corrosion-resistance and self-lubricating properties. Most engineers and production men are familiar with the proprietary surface coatings on piston rings which have yielded a veritable harvest of results in prolonging the life of cylinder bores and pistons, decreasing blow-by, increasing oil economy. The coating of rings, while of recent origin, is practiced so widely and has been the subject of such extensive treatment in current literature that we shall make but passing reference to that phase of the subject. The coatings to which we shall refer, fall into two general categories—metallic and chemical. It is of more than passing interest to note that a general appreciation of such coatings dates from the introduction of coated rings as standard equipment by most motor car manufacturers. Nevertheless, even in this extraordinarily brief period, these surface coatings have gained unusual favor and bid fair to broaden the scope of application. It is fitting to say right at this point that research into the unique properties and/or limitations of wear-resisting coatings is going on in many directions since the art is young and many characteristics have yet to be explored. Fact of the matter is that one of the prominent investigators in this field cautions that such coatings must not be considered as a panacea for all ills, emphasizing that coatings cannot take the place of sound design. Coincident with these developments is an appreciation of the role of self-lubricating properties as an aid in combatting wear and scuffing in the surfaces thus treated. It is claimed that one of the most effective treatments to this end is the use of colloidal graphite which is carried into the granular structure of the coating by dipping in a light oil bath. In the category of commercially available protective treatments which may be employed where best suited, we can list the following: Parker Rust Proof, Bonderizing and Parkerizing chemical coating. American Chemical Paint, “Thermoil-Granodine.” Ferrox, oxidizing surface treatment. Standard Oil Co. of California, sulfidizing chemical coating having E-Z properties. We also may include the basic coatings in use for many years, such Metallic Automotive Industries April 15, 1939 | ||