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particular steel begins to solidify, plus the loss of temperature from when the reading is taken to when the steel gets to the farthest end of the thinnest section in the casting. A further query to this second part of the question invariably was: “But how are we to know what these two values are?” The first value depends on the composition of the steel, the carbon contents being the principal factor. This can be obtained by reference to a standard carbon-iron curve, such as shown in the accompanying illustration. For a steel containing 0.25 per cent carbon, trace the line A B till it intersects at C giving a value on this curve oi 1492 degrees Cent. (2720 degrees Fahr.); for a steel containing 0.65 per cent carbon, trace the line DE till it intersects at F, giving a value 1476 degrees Cent. (2690 degrees Fahr.), and so on. For other elements in the steel commonly used in castings the variation is not of importance and does not compare with the many other sources of error that crop up in reading the temperatures of molten steel in a foundry. The second value depends upon such variables as the heat of the ladle, the thickness of ladle lining, time of reading to pouring, whether molds are of dry or green sand, and thickness and lengths of the thinnest sections. All of these factors depend very much upon local conditions, and it is . regarding this problem that constant consultation between the man responsible for the steel in furnace and the man respor.sible for making up the molds is so valuable. Final results are only obtained by the constant comparison of the quality of the final castings with the results obtained by their methods of reading the temperatures of the steel.

Discussion-Temperature Control

Mx. C. H. Booth.-I simply want to comment on what Mr. Brooke calls the skin test. We find that for small castings of thin section, timing the forming of the skin on a small lad!efull is the most accurate method of getting the proper temperatures. In the timing accurately of metal of the same analysis, steel will pretty nearly produce practically the same result in casting if the mold is correctly made.

MR. WHITE.- I would like to pay a tribute to the film tests, having poured more than 5000 tons of steel of the same analysis, that is, carbon between 0.30 and 0.35. I believe carbon is a governing factor to a great extent. We have not had more than three cold heats nor have we had more than eight cracked ingots.

Mr. L. B. LINDEM UTII:- The greatest trouble in electric steel practice is making the steel too hot. Most of the tests that are commonly used in open-hearth steelworks indicate whether the steel is hot enough but do not indicate whether it is too hot. In my opinion a very satisfactory test is that where the estimate is made according to the surface tension. The hotter the steel,

, the greater will be the surface tension. You can tell the temperature by the way the steel rises at the edge of the spoon. You also can tell whether it is too hot. Its greatest value is that it will not let you pour the steel too hot.

Mr. F. W. BROOKE.-The molders do not like the film test quite so much, especially if they are on a production basis, because it shows up the condition of the steel far better than the pouring test. If there is the slightest sign of wildness in the steel, that is, if the steel hasn't been dead killed, then it will show up in this film test.

The temperature of the steel is affected to a certain amount by the analysis of the steel. A low carbon has a higher melting point than a high carbon, although those differences are not so marked. The best way to get at it is to refer to the ironcarbon curve, which quickly will reveal the difference.

Mr. Joseph A. STEINMETZ.—Do atmospheric conditions have any effect on the film test?

MR. BROOKE.—Yes. In taking a film test it is absolutely important that there are no drafts in the shop. If there is a good wind blowing through the shop it is going to spoil the filmi test each time.

Mr. S. H. QURBACHER.--Which test do you think is best under varying carbon conditions? Do you think the pouring test would work better-say if the carbon varied quite a bit?

MR. BROOKE.—In the first place, I really think that two tests should always be taken. Where there is any doubt never depend on one test only. My experience in going around steel mills is that the rod test is not being used enough. The large steelworks in Italy brought this rod test to a very fine degree. They decide on certain types of steel and use certain types of rods. For instance, on high carbon tool steels, they use a rod of 38-inch diameter and a certain composition. The time element also comes into that. The melter can leave the rod in the bath just the exact number of seconds and note the effect of it.

MR. BROOKE.-Can anyone explain the kick test?

MR. THOMAS.-The test I have been accustomed to is to move a rod back and forth through the metal until the kick is felt. It is then drawn out and the melter determines by the shape of the point or the cut whether or not the steel is ready to pour. The best way to describe what we considered a good tenperature was to cut it off-just as if we were cutting a potato with a paring knife.

THE CHAIRMAN, R. A. BULL.—How does the kick feel?
MR. THOMAS.-It feels like a bass biting on the line.

MR. LINDEMUTH.—The kick is only a vibration, not a sudden jar, and occurs all the time the rod is in the steel. I think it represents the cutting action on the rod. When a heat is stirred with a rod, the rod comes out with what is called a rat tail. You feel very little kick when you are stirring, but if when you bring it out it looks as though somebody had bitten pieces out of it, you will get the kick. It is the centrated cutting on the rod, I think, that produces the kick or vibration. THE CHAIRMAN.--The sudden shortening of the rod and the consequent effect on the balance of it may have a great deal to do with that. Is there a vibration ?

MR. LINDEMUTH.—0, yes. The temperature test is partly the feeling of this vibration.

MR. BROOKE.---Is it necessary to get this kick or is it really just a variation of the rod test?

Mr. LINDEMUTH.-If there is any difference in the temperature of the steel and the rod after the rod gets up in temperature there will not be any kick. When the rod is brought out-and it probably is only hot-there are big gouges chewed out of the steel, showing that the rod never attained the temperature of the bath.


Report of Committee on Steel

Foundry Standards


The foundryman who has crude-oil-burning appliances in his foundry has occasion to know the actual oil consumed by any one or all of the many types of burners on the market. Realizing the impracticability of installing standard meters for each burner, and also that their record is of value for an average metering over a long period, your committee beg to present a design of a portable, automatically controlled oil meter.

This meter may be made in any desired size and may be attached to any individual oil burner and should furnish a very accurate record of the quantity of oil consumed.

The device consists essentially of two vertical cylinders, capped and connected each with the other, both top and bottom, as indicated in the accompanying illustration. The pipe diameter may be of any dimension desired. If a pipe of a diameter much larger than 8 inches is used, a larger factor of error is introduced; and if a pipe of smaller diameter is used, the size of the meter becomes unpractical.

The operation of the meter consists essentially of filling one of the cylinders with oil through the 4-way valve to a level as indicated and at which the float will have actuated the switch and through the solenoid shut off the oil supply. It is then necessary to measure in inches the height of the oil column as indicated on the gage glass and to compute the volume of oil represented in the pipe of chosen diameter. The cock in the top connection is now open and compressed air is permitted to enter the system. The pressure as indicated on the gage will be approximately the oil pump pressure. The air connection is now closed and the meter is ready for operation. The oil in the cylinder, on its source of supply being

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