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Another 'Crucible Steel' reference, published in 1872, setting off crucible steel as different from (and preferred to) Bessemer - processed steel:

Title: About Bessemer and crucible cast steel.
Author: Anonymous
Reference: 1872, Volume 205, No. XLII. (Pp. 113–118)
Url: http://dingler.culture.hu-berlin.de/article/pj205/ar205042

XLII. About Bessemer and crucible cast steel.
From the organ for the progress of the railway industry, 1872 p. 125.
In some places in Germany and Austria there is a prejudice against Bessemer cast steel, which has long been overcome in other countries (we mean England, Belgium and France).

This fact is probably due to the fact that the Bessemer cast steel in the former countries, the herd of crucible cast steel manufacture, meets with particularly strong, often not entirely honest, competition. Little by little, the opinion has been established among many that Bessemer cast steel is not permitted for this or that purpose.

So one prescribes crucible cast steel for some deliveries and thus excludes Bessemer cast steel, without considering that there are also smaller and better types of one or the other of these products depending on the quality of the raw material used. The Bessemer cast steel is simply excluded from the competition and the consumer thus blocks the way for himself to gain experience with a far cheaper product, equally good if made well, as the best crucible cast steel.

More than that: many cast steel works manufacture both Bessemer cast steel and crucible cast steel.

The former, cheaper, is excluded from competition. So you set the prices for the second, more expensive. But are the goods always delivered in crucible cast steel? We would like to doubt this. It is almost impossible to distinguish crucible cast steel and Bessemer cast steel with the same careful fabrication. We have misled the best workers and masters through comparative experiments so that they could no longer distinguish the origin of the various samples. We ourselves have become mad about it, and the laboratory alone could always tell the difference. In fact, the crucible cast steel always contains a higher percentage of Sicilium than the Bessemer cast steel. By excluding Bessemer cast steel from competition, even if the manufacturer wants to assume the required guarantee,Consumers a rise in prices without in the least getting the security of getting better goods. Such exclusions simply prevent those plants from participating in the submission which only Bessemer cast steel | 114 |and despise building a small crucible casting plant pro forma , even if it would remain almost unused in order to be able to offer crucible cast steel.

Incidentally, how do the supporters of crucible cast steel want to explain that this steel can meet higher requirements than well-prepared Bessemer cast steel? Pig iron of the very best brands is used for good Bessemer cast steel. Cast steel is blown directly from such iron. Crucible cast steel, on the other hand, is usually made from wrought iron and steel waste of various origins. For good crucible cast steel only those types of wrought iron are used which, by virtue of their purity and quality alone, are suitable for producing a good product. These wrought irons can of course also be made from the very best brands of pig iron. The original raw materials for good steel are therefore always the same, "good brands of pig iron", only the fabrication method varies for the different types of steel. In the fabrication methods in and of themselves, however, no reason can be found which speaks in favor of crucible cast steel against Bessemer steel. One can make the proposition that if the quality of the raw material used is equally good and if the manufacture is equally careful, the finished product produced will be equally good in both cases.

The manufacture of cast steel according to the Bessemer method seems to offer us the advantage even for the consumer that the control over the origin and quality of the raw material used is far more reliable. This so important control is, in fact, easily accomplished here, while it is almost impossible in the manufacture of crucible cast steel. A closer look at the origin of the iron used for the crucible cast steel fabrication will explain this. It is produced on a large scale from scale iron as well as from scrap steel and iron and from old wrought iron of the most varied origins. Even the waste from the Bessemer cast steel fabrication is transformed into crucible cast steel by simply remelting it in the crucible.

Excellent types of crucible cast steel are made from the best known types of wrought iron; but such types of iron are of course very expensive, and are therefore only manufactured in smaller quantities. Such crucible cast steel is only used for the manufacture of finer, smaller steel goods (scissors, knives, etc.). For pieces of significant weight | 115 |it is not used; these are only made from the former, the crucible steel made from shell iron, Bessemer cast steel and iron scrap and old wrought iron.

The crucible cast steel therefore often leaves much to be desired with regard to the purity of the raw material used. At least the way it is fabricated does not offer the easy control that is required with Bessemer cast steel, that only pure types of iron are used. Here, in fact, the customer can easily be certain which brands of iron are used for his orders. With the crucible cast steel, however, this is almost impossible; the above-mentioned circumstances clearly show that in many cases it is not even possible for the manufacturer himself to know the origin and the perfect uniformity of the types of iron used.

In this circumstance, it seems to us that there is an advantage on the part of using Bessemer cast steel. Another circumstance which in many cases makes the use of Bessemer cast steel preferable is the greater uniformity of the products which can be achieved when using Bessemer cast steel. The crucible cast steel is melted in small crucibles, each of which is approx . Holds 50 lbs.

To pour heavy pieces, many such crucibles are emptied into a mold. Only if the iron used, the aggregate and the silicon content of the crucibles are completely identical, as well as with completely identical degrees of heat when melting in the crucibles, will the same steel quality be achieved in all of them. It is therefore very rare for crucible castings to be completely homogeneous. The laboratory teaches that the two ends of an axle forged from a block of crucible cast steel almost always have a not insignificant difference in carbon content. The often so great difficulties in machining cast steel stem from this difference in carbon content.

This extremely damaging difference in composition, observed in the manufacture of heavy pieces, can of course also be demonstrated in the case of various small blocks.

This difference in the quality of the product obtained is the reason why, for some purposes, the crucible cast steel has been completely knocked out of the field by the Bessemer cast steel, because the latter is always blown in a larger batch ( about 4 tons) Texture is completely homogeneous, even with a little attention to the great uniformity in the raw material | 116 |for the sake of it, it is easy to achieve a perfectly uniform product from different casts.

This great uniformity in production is the reason which has made it possible for the manufacturers of Bessemer cast steel in France and Belgium to displace crucible cast steel even where the highest demands are made on the material used, in the manufacture of rifles.

The Chassepot rifles of the French army are made exclusively of Bessemer cast steel, especially those made by Messrs. Petin and Godet .

In Belgium, the Bessemer plant of the John Cockerill company has completely displaced cast steel crucibles for rifle manufacture (especially the Albini rifles). Bergischer crucible steel was used here earlier. The crucible cast steel has also been beaten by Bessemer cast steel in other fabrications subjects. Axles and drums for locomotives and tenders are hardly known anywhere in England in any material other than Bessemer cast steel. The London and North Western Railway has its own Bessemer plant (at Crewe) with an annual production of approx . 16,000 tons of drums, axles, forgings and rails.

The express train locomotives of this line, which run 50 to 60 English miles an hour, have drive wheel bandages made of Bessemer cast steel (2.30 meters outer diameter). Crank axles, crank rods and coupling rods, in short all parts of these locomotives, which must be of great resistance, are manufactured by the company in its own works from Bessemer cast steel.

These works in Crewe are directed by the engineer Ramsbottom , a man who is unrivaled in engineering on the Continente. The great extent that such a technician gives the application of Bessemer cast steel is in and of itself a guarantee that it can be used with the best material of another origin without hesitation.

In Belgium, too, only Bessemer cast steel is used for all axles, curved axles and bandages for locomotives, tenders and wagons. It is perhaps also interesting to note that in the last major attempts at guns of the heaviest caliber in Belgium, the new cast-iron 11-inch guns reinforced with tires made of Bessemer cast steel, achieved excellent results, while the two attempted Krupp 's crucible cast steel Cannons were taken out of service during the attempt.

| 117 |
This information may suffice to show that what matters less is the fabrication method used to produce the type of steel used than the care and expertise with which it was manufactured and processed.

The quality of the products, determined by the tests stipulated for each delivery, and the guarantee conditions to be provided should only be decisive when deciding on the quality to be used, regardless of the method by which the steel is produced.

Incoming samples upon acceptance of the delivery would protect the public far better from accidents, and would also give railway technicians greater security for good fabrication than the route so often followed today. The tests are often carried out in the following way: In addition to the condition we criticized that a certain material quality should be used for the fabric, a test is usually prescribed, for example with the 50th or 100th piece. In some cases, these test regulations contain conditions that are so difficult that they can only be withstood by very unusual pieces, which cannot be obtained in manufacturing practice as ordinary fabric and at moderate prices. We want such pieces to be "exhibition pieces "call. Such rare fabricates can probably be attributed to the experiment if one is familiar with the mild procedure of some railway administrations, which do not carry out the full number of the stipulated experiments but, in order to save time and costs, leave it to one single for a whole delivery. The method used in others seems more rational to us, where the experimental conditions are more lenient, so that every well-worked piece, as is produced by conscientious manufacture, can exist with the prescribed samples. Such experimental conditions are especially prescribed in some royal directions.

The experiments are then carried out with the utmost rigor in the presence of a high-ranking official on the whole number of specimens stipulated. If a delivery can stand such trials, one has the full assurance that it will withstand any request from service. As a counterpart, we particularly emphasize the Austrian procedural method. There the experiments seem to be prescribed by pure theorists. They are very rational, but mostly so strict that, for example, the best-worked axle could not meet the test specifications if they were really handled with the utmost rigor. But where is the limit when a web Direction allows the decreasing officials at removal | 118 |not to observe the prescribed test conditions with full rigor?

It seems to us that more lenient, but more rigorous, and larger-scale experiments give a far greater guarantee of good fabrication. With regard to the comparative experiments between Bessemer cast steel and crucible cast steel fabricates, it is to be regretted that so few railways have so far taken a completely impartial standpoint.

There are not so many of the steel factories in Germany which are involved in deliveries for iron supplies that inexhaustible tests could soon determine the quality of the fabricates of most of the great works. As far as we know, such experiments have not yet been carried out on a really large scale. It would be interesting, for example, to try to place an axle made of crucible steel and one made of Bessemer cast steel under a large number, perhaps 100 wagons. One would have to wait some time before the final result could be determined with certainty by breaking tests on the axles, but the result of such an experiment would be taken from practice and would be decisive. A similar experiment could also be carried out for bandages with certain final results. Such attempts would be crucial

Source: http://dingler.culture.hu-berlin.de/article/pj205/ar205042

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