Local Surface Hardening of High Tension Steels - Industrial

Local Surface Hardening of High Tension Steels. Ind. Eng. Chem. , 1914, 6 (4), pp 349–349. DOI: 10.1021/ie50064a042. Publication Date: April 1914...
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APT., 1914

T H E J O C R S d L O F I N D G S T R I A L A N D E N G I N E E R I X G CHEMISTRE’

Renault machine) had a two-cylinder, 12 H. P. engine of 1 0 . 2 cm. bore and 1 2 . o cm. stroke. il preheater, heated by the exhaust, and a special vaporizer were built in. Under the supervision of officers of the Conservatoire des Arts et M6tiers in Paris, a round trip of 105.4 km. was run. The average speed was 3 4 , 4 km. per hour, and the maximum 4 2 . 3 km. per hour, 14,996 kg, of naphthalene were used, or 0.142 -kg. per km., which, a t a price of 2 . 5 cents per kg. would mean 0,335 cent per km., as against I cent per km. for gasoline. The engine was run 13 min. ,37 sec. on gasoline before the naphthalenewas turned on,and could be started without gasoline after a I O min. stop or by priming the cylinders with gasoline after a 16 min. stop. Further than this there were no difficulties; the exhaust was almost smokeless and there was no deposit in the cylinders. The second experiment was with a pard locomotive (shown in the figure) built by Schneider Pr Co. of 19 metric tons service weight and 2500 kg. maximum tractive power. I t had four cylinders, cast in pairs, of 14 cm. diameter and 20 cm. stroke. With benzene i t developed 7 2 H. P. a t IOO r. p. m. and used 280 g. per H. P. per hour. The cooling water was circulated by convection and passed through a jacket around the naphthalene container b , keeping the fuel molten. The liquid naphthalene was pumped from the container to the vaporizer above the cylinder head. Raw naphthalene a t 2-2.5 cents per kg. was used. The results of the tests were favorable and showed the machine practical, but more exact data are not yet a t hand. REMOVAL OF BLAST FURNACE OBSTRUCTIONS WITH EXPLOSIVES According to H. Schonweg, Zeitschr. ges. Schiess- u. Sprengstof., 8 (1913), 445-448, obstructions which completely prevent the passage of the blast in blast furnaces may be removed by dynamite without injuring the furnace. The charge is usually about 600 g. but may be as large as 1,2j o g., provided it is exploded 40-50 cm. from the furnace wall. The dynamite is fired by a fuse, the charge being contained in a tube enclosed in a second tube (in which it must have free play) projecting through a hole drilled in the furnace wall. TRANSPORTATION OF CHEMICALS BY WATER I n Chenz.-Ztg., 38 (1914), 146, J. Aeby discusses the above problem from the point of view of the transportation expert in the light of the lessons learned from the Volturno disaster. I n the English investigation of this accident it appeared t h a t barium peroxide was the original cause of the fire; therefore, there is, the author believes, danger that this product will be boycotted and its transportation by water surrounded with difficulties, as is already the case with sodium and potassium peroxide. Admitting that barium peroxide was the primary cause, he however points out that the fire would never have occurred unless this substance had been shipped with inflammable organic substances. Since i t cannot be expected that transportation companies and steamship lines shall have expert chemical knowledge of the goods they carry, the author considers i t the duty of shippers, in their own and the public’s interest, to advise the transportation companies as to the nature of goods shipped, so that for example, neither peroxides nor permanganates shall be shipped in the same cargoes as inflammable organic substances, strontium nitrate, etc.

A NEW GERMAN SILK MILL Michels Sr Cie have recently built a new- silk mill a t Nowawes, near Berlin, which is described in the Zeitschift des Vereines deutscher Ingeniewe, 58 (1914), 6, j 3 . Aside from the mechanical perfection of the plant, its appearance has not been neglected,

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great pains having been taken t o make the building and its approaches artistic. These efforts towards beauty- are considered t o have a direct advertising value and so are economically justified. They are helped by the fact that the shed type of factory with its ugly saw-tooth roof was abandoned in favor of one with a large central skylight, which assures each machine a supply of diffused daylight without shadow.. -111 the machines are driven by individual electric units, which receive current from the power plant in the lower story. The piping and wiring pass for the most part through &is story, so that necessary repairs will cause the least possible interruption of manufacture. The ventilating, heating and humidifying systems are so designed t h a t the air can be changed in winter once, in summer four times per hour. The whole plant cost $17o,ooo, of which $40,000 was spent in preparing and improving the grounds. WHALE OIL

H. T. Offerdahl-Larvik gives the following facts about whale oil in Bey. d . deutsch. Pharm. Ges., 23 (1913), 558-559: The world’s output in 1912 was 1,200,000bbl. of (7jo kg. each), more than half of which came from the Norwegian fisheries. I n 1904-1905 the cost of producing I ton of oil was $67.50; in 1912, owing to higher wages, $94, j o . After the first separation of the oil, the flesh and bones are dried a t 3o0°-4000 C., re-pressed, and used for fertilizer. This contains 10-12 per cent nitrogen, 14-1 j per cent phosphoric acid, and not more than 3 per cent oil iE i t is of good quality. \$;hale oil is now hydrogenated exclusively for soapmaking, but the author believes it has a value as a foodstuff, and that the nickel present, left after the hydrogenation, is absolutley non-toxic. ITALIAN AUXILIARY MARINE DIESEL ENGINE In THISJOURNAL, 6, 259, an account was given of a passenger vessel equipped with large Diesel engines. At the time of the adaptation of this type of engine to marine service it mas freely predicted that a new era of prosperity was in store for the auxiliary sailing vessel, and this prediction has to some extent been fulfilled. One of the latest vessels of this type is the Italian three-masted schooner ‘‘Bosta,”d1050 tons, described in Engineering (London), 97 (1914), 182. Her engine is of the two-stroke-cycle type with four cylinders of 350 mm. (13 .75 in.) diameter and 500 mm. (19.7 iii.) stroke, giving a t 2 0 0 r. p. m. about 440 brake horse power, corresponding to the comparatively high mean effective pressure of 1 2 7 lb. per sq. in., assuming the engines to have a mechanical cfficicncy of about 7 3 per cent. The engine is a good example of modern Italian engineering Dractice and is uninue in almost all its orincir,al features. LOCAL SURFACE HARDENING OF HIGH TENSION STEELS According t o Engineeriizg (London), 97 ( I 9 I + ) , 2 I 2 , hIessrs. Y’ickers have perfected a t their River Don \Torks, :it Sheflield, a system of surface-hardening which can be applied t o any local part of any casting or forging of high-tensile steel, without involving distortion and without destroying the effects of the usual heat treatment to which the whole casting or forging may have been subjected. The equipment includes merely the outfit usually supplied for oxyacetylene welding purposes ; four sizes of burners meet all general’requirements. The work t o be hardened locally is placed in a tank of water with adjustable overflow, so that the water-level can be regulated, as while the portion of the surface being hardened is instantly heated to the required temperature, the whole of the remainder of the article is kept as cool as possible by being immersed in water. Should this be impossible, the part not being hardened must be kept cool by water flowing over the surface. The burner is held so