Research and methods of analysis of iron and steel at ARMCO.

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1920 Excerpt: ...turned to the position, which admits carbon dioxide-free air; this should pass at the same rate as the oxygen. During this combustion period, if directions have been followed, all carbon dioxide will have been removed from the furnace, but some still remains in the large bulb of the absorption apparatus. The air removes this. The advantage of the use of air at this stage is obvious: a saving of oxygen is effected and the furnace is immediately available for burning the next sample. While air is passing through the first tube (requiring VA to 2 min.) the combustion of the next sample proceeds as already directed, using the second absorption tube. The second reading of resistance and temperature on the first tube then follows, and if the solution is not too dilute it can be used for absorbing the carbon dioxide from other samples; otherwise, a little is allowed to flow into the reservoir G, and the tube is filled to the mark again with fresh solution. Of course it is an economy in time for the operator, wherever possible, to choose conditions (weight of sample, carbon content of same, etc.) so as to get the maximum number of determinations for a single filling, since in this way the 1 The melting point of gold is a convenient temperature check. If this metal is not melted the temperature is too low. See paper cited, by Cain and Maxwell. 2 Experience has shown that no loss of carbon occurs unless the sample contains extremely fine particles; with most steels these can first be removed without causing an error in the carbon determination. This point should always be tested, however, in burning new steels. second resistance and temperature readings serve as initial values for the next combustion and so on. The solution should not be used when it is more dilute t...