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Full text of "Metallurgy Of Cast Iron"

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That " Bessemer iron " can often take the place of "Foundry," and in some cases prove a better product ' to make castings with, is a fact which few founders have up to this writing discovered. In the years 1893 and 1894 of business depression, Bessemer pig was selling cheaper than Foundry pig. A few founders, who did not require high phosphorus and knew it, took advantage of the low price of Bessemer. Founders never having" had an experience with Bessemer pig metal will be somewhat surprised to learn that the best experts cannot tell *' Bessemer '' from *' Foundry '' by judging* of its fracture; nevertheless this is true. It is only by analysis that the difference is to be made known, and that mainly exists in the phosphorus being lower in Bessemer than Foundry, as illustrated in Table 30, page 215.
Regular Bessemer ranging from 1.40 to 1.60 in silicon, .010 to .030 in sulphur and about .45 in manganese, can often be well used for hydraulic or steam cylinders, heavy dies, machinery castings, and for gear wheels of one and one-half inch pitch and upwards.
For ordinary machinery castings that average from one and one-half inches up to two inches thickness of metal, Bessemer ranging from 1.60 to 1.90 in silicon would be found to work very well. The author hase in the chemical analysis of one sample of drillings by different chemists. There is much more that might be said on the subject of this chapter, but the author trusts that the principles herein advanced will aid the work of bringing about the reform in grading or buy-ing pig iron by analysis which this chapter advocates, and which almost all now concede should be accomplished. when the character of iron is noticeably changed, and not something that is so flexible that anyne castings. analysis which may be given is simply an average of the whole, generally taken from the two ends andith the uncertainty of furnace workings when in urgent need of ten hundred             jon of iron; and Sir........................    2,720     "