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).
Review of metallic and chemical coatings for engine parts and water repellent treatments for seat covers.
| Identifier | ExFiles\Box 142\2\ scan0431 | |
| Date | 15th April 1939 | |
| 494 METALLIC AND CHEMICAL COATINGS parts where resistance to wear is essential. To this end they are experimenting on valve stems, valve guides, piston pins, and cylinder liners for the aircraft engine. On the 4CHO-150 truck engines they expect to Bonderize the cast iron pistons. Ferrox-treated Perfect Circle rings are used as standard equipment on both engines. American Chemical Paint Co., has made remarkable progress in automotive applications with its “Thermoil-Granodine” process. It is said to have been successfully applied to piston rings, pistons, valve tappets, axles, gears, camshafts, screws, parts of carburetors, etc. It creates the surface found on the well-known Granoseal piston rings. It is equally easy to apply in small- and large-scale production. At its boiling temperature, Thermoil-Granodine reacts with the metal and transforms its surface into a layer of iron and manganese phosphates integrated with the metal beneath. This peculiar coating, when oiled and used as a bearing surface, quickly becomes so smoothly burnished that friction is reduced to such an extent that scuffing and tearing of the metal are eliminated. When the iron or steel parts are to be treated with Thermoil-Granodine, they must be first cleaned, using a spirit solvent, or solvent vapor, or an alkaline solution followed by a water rinse. This treatment prepares the parts for immersion in the boiling chemical solution. Here they remain for a time varying from ten minutes to an hour. After the chemical bath, the parts are rinsed in hot water, and then dried. If desired, the further protection of a thin oil-film may be provided by dipping the parts into oil, or into an emulsion of a “soluble” oil. The A.C.P. process is currently used for treating the camshafts of a large number of production engines, including passenger car and truck engines. It is in use for coating valve tappets and lifters; and on a variety of other parts where wear-resistance or corrosion resistance are desired. Typical of the camshaft treatment is the new installation for the engine of The Champion, recently announced by Studebaker. The A.C.P. coating is applied rapidly in a simple piece of equipment comprising five immersion tanks having the following cycle of events: 1. Electrolytic clean (alkaline bath) 2. Hot water rinse 3. Granodine chemical bath, held at 190-200 deg. F.{Mr Friese} 4. Hot water rinse 5. Dip in soluble oil, serving as rust preventive Hudson is another prominent motor car manufacturer who has adopted the Thermoil-Granodizing process for treating the cam surfaces of camshafts. According to the company, this process is used to eliminate the harmful effects of the break-in period. The treatment produces a self-lubricating effect said to add greatly to the life of the camshaft. Unique application of the A.C.P. coating is found at Graham-Paige where the sides of the lower end of connecting rods are treated to prevent scuffing during the initial run-in period. According to G-P engineers, the coating when subjected to friction, burnishes quickly and thereafter reduces wear to a remarkable degree. The new coating takes the place of the copper-plating formerly used for the same purpose. Cadillac uses hydraulic lash adjuster cylinders and tappet bodies with Ferrox surface treatment. In addition, Cadillac uses Ferrox-treated Perfect Circle rings. Now a word concerning the role of colloidal graphite as an adjunct Automotive Materials Water Repellent for Seat Covers For the past few years “Aridex” water repellent, product of E.{Mr Elliott - Chief Engineer} I. du Pont de Nemours & Co., has been applied to many automobile seat covers made from textile fabrics. More recently the Wortendyke Mfg. Co., Richmond, Va., adopted “Aridex” for its Flexine paper fiber fabrics, used for the same purpose. Besides giving them the advantages of water repellency and spot and stain resistance, the du Pont product is said to make easier the handling during manufacture. These fabrics are converted into automobile seat covers by the Crawford Mfg. Co., of Richmond, Kansas City, and Dallas. Spots and stains are easily removed from these paper fabric seat covers by sponging or wiping. The fabrics do not wet through readily, and, if wet by pressure or a heavy storm, dry out in a fraction of the time required by untreated fabrics. It is claimed that “Aridex” does not coat or seal the fabric. The repellent finish forms an invisible [Image Caption] New manufacturing equipment was developed to mold ribs on truck trailer brake drums made of Meehanite cast iron described on page 506. The photograph shows the cope and drag equipment, together with the power-driven slick which is also a Meehanite casting April 15, 1939 Automotive Industries | ||