Heat Treatment Of Gear Blanks
: HEAT TREATMENT OF STEEL: The Working Of Steel
This section is based on a paper read before the American Gear
Manufacturers' Association at White Sulphur Springs, W. Va., Apr.
18, 1918.
Great advancement has been made in the heat treating and hardening of
gears. In this advancement the chemical and metallurgical laboratory
have played no small part. During this time, however, the condition
of the blanks as they come to the machine shop to be machined
not received its share of attention.
There are two distinct types of gears, both types having their
champions, namely, carburized and heat-treated. The difference
between the two in the matter of steel composition is entirely in
the carbon content, the carbon never running higher than 25-point
in the carburizing type, while in the heat-treated gears the carbon
is seldom lower than 35-point. The difference in the final gear
is the hardness. The carburized gear is file hard on the surface,
with a soft, tough and ductile core to withstand shock, while the
heat-treated gear has a surface that can be touched by a file with
a core of the same hardness as the outer surface.
More
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The kind of steel used in the die of course influences the heat treatment it is to receive, but this also depends on the kind of work the die is to perform. If the die is for a forging which is machined all over and does not have to be especially cl... Ebbw Vale And The Bessemer Process
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This shows the result of tests by C. R. Hayward and A. B. Johnston on two types of steel: one containing 0.30 per cent carbon, 0.012 per cent phosphorus, and 0.860 per cent copper, and the other 0.365 per cent carbon, 0.053 per cent phosphorus, and ... Effect Of Different Carburizing Material
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Heat very slowly and carefully to from 1,800 to 2,000 deg.F. and forge thoroughly and uniformly. If the forging operation is prolonged do not continue forging the tool when the steel begins to stiffen under the hammer. Do not forge below 1,700 deg.F... Furnace Data
In order to give definite information concerning furnaces, fuels etc., the following data is quoted from a paper by Seth A. Moulton and W. H. Lyman before the Steel Heat Treaters Society in September, 1920. This considers a factory producing 30,0... Gas Consumption For Carburizing
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The material used for all gears on the Liberty engine was selected at the option of the manufacturer from the following standard S. A. E. steels, the composition of which are given in Table 12, TABLE 12.--COMPOSITION OF STEELS NOS. X-3,340 AND 6,1... Hardening
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Steel is hardened by quenching from above the upper critical. Apparently the quick cooling prevents the normal change back to definite and sizeable crystals of ferrite and cementite. Hardness is associated with this suppressed change. If the change ... Hardening Carbon Steel For Tools
For years the toolmaker had full sway in regard to make of steel wanted for shop tools, he generally made his own designs, hardened, tempered, ground and usually set up the machine where it was to be used and tested it. Most of us remember the to... Hardening High-speed Steel
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We will now take up the matter of hardening high-speed steels. The most ordinary tools used are for lathes and planers. The forging should be done at carbon-steel heat. Rough-grind while still hot and preheat to about carbon-steel hardening heat, th... Hardening Operation
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This section is based on a paper read before the American Gear Manufacturers' Association at White Sulphur Springs, W. Va., Apr. 18, 1918. Great advancement has been made in the heat treating and hardening of gears. In this advancement the chemic... Heat Treatment Of Lathe Planer And Similar Tools
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The heat-treating department occupies an L-shaped building. The design is very practical, with the furnace and the floor on the same level so that there is no lifting of heavy pots. Fuel oil is used in all the furnaces and gives highly satisfactory... Heat-treating Equipment And Methods For Mass Production
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Another form of heat-treating furnace is that which is used for the heating of manganese and other alloy steels, which after having been brought to the proper heat are drawn from the furnace into an immediate quenching tank. With manganese steel in... Heavy Forging Practice
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