To secure proper hardness, the cooling of quenching of steel is as important as its heating. Quenching baths vary in nature, there being a large number of ways to cool a piece of s...
As soon as the temperature of the steel reaches 100 deg.C. (212 deg.F.) the transformation begins, increasing in intensity as the temperature is raised, until finally when the lowe...
The blacksmith in the small shop, where equipment is usually very limited, often consisting of a forge, a small open hard-coal furnace, a barrel of water and a can of oil must have...
The matter to which these notes are primarily directed is the introduction of carbon into the case of the article to be hardened. In the first place the chances of success are incr...
In the heat treatment of steel, it has become absolutely necessary that a measuring instrument be used which will give the operator an exact reading of heat in furnace. There are a...
The potentiometer pyrometer system is both flexible and substantial in that it is not affected by the jar and vibration of the factory or the forge shop. Large or small couples, lo...
In heavy forging practice where the metal is being worked at a welding heat, the amount of flame that will issue from an open-front furnace is so great that a plain, sheet-steel fr...
The voltage generated by a thermo-couple of an electric pyrometer is dependent on the difference in temperature between its hot junction, inside the furnace, and the cold junction,...
This is remedied by reheating the piece to a temperature slightly above the critical temperature of the case, this temperature corresponding ordinarily to that of steel having a ca...
Automatic temperature control instruments are similar to the Brown indicating high resistance pyrometer with the exception that the pointer is depressed at intervals of every 10 se...
In spite of a rapid increase in the use of machines and the overwhelming demand for iron products for the expanding railroads, the use of steel had expanded little prior to 1855. T...
Do not hesitate to ask for information from the maker as to the best steel to use for a given purpose, mentioning in as much detail as possible the use for which it is intended. Do...
The selection of a standard analysis by the manufacturer is the result of a series of compromises between various properties imparted to the steel by the addition of different elem...
The following information has been supplied by Automatic and Electric Furnaces, Ltd., 6, Queenstreet, London, S. W.: Two gages of 3/4 in. diameter, 12 threads per inch, were heated...
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 t...
All users of tool steels should carefully study the different qualities of the steels they handle. Different uses requires different kinds of steel for best results, and for the pu...
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 he...
In large heat-treating plants it has been customary to maintain an operator at a central pyrometer, and by colored electric lights at the furnaces, signal whether the temperatures...
The Society of Automotive Engineers have adopted certain heat treatments to suit different steels and varying conditions. These have already been referred to on pages 39 to 41 in c...
How are we to know if we have given a piece of steel the very best possible treatment? The best method is by microscopic examination of polished and etched sections, but this requi...
The carbon content of this steel is above 30 points and is hardly ever above 60 points or 0.60 per cent. Annealing such steel is generally in quantity production and does not requi...
That Mushet was "used" by Ebbw Vale against Bessemer is, perhaps, only an assumption; but that he was badly treated by Ebbw Vale is subject to no doubt. Mushet's business capacity...
At the works of the Dayton Engineering Laboratories Company, Dayton, Ohio, they have a large quantity of small shafts, Fig. 40, that are to be case-hardened at A while the ends B a...
Hardening a gear is accomplished as follows: The gear is taken from the furnace by the furnaceman and placed in the lower die, surrounding the centering jaws, as shown at H in Fig....
So much depends upon the forging of steel that this operation must be carefully supervised. This is especially true because of the tendency to place unskilled and ignorant men as f...
In Fig. 56 is shown the packing pots where the work is packed. These are of malleable cast iron, with an internal vertical flange around the hole A. This fits in a bell on the end...
Each furnace is equipped with pyrometers, but the reading and recording of all temperatures are in the hands of one man, who occupies a room with an opening into the end of the har...
The hard parts of the gear must be so hard that a new mill file does not bite in the least. Having passed this file test at several points, the gears go to the center-punch test. T...
The following illustrations from the Taylor Instrument Company show different applications of the thermo-couples to furnaces of various kinds. Figure 118 shows an oil-fired furnace...
The requirements for materials for the Liberty motor connecting rods are so severe that the methods of securing the desired qualities will be of value in other lines. The original...