US1325114A - Electroconverter-furnace. - Google Patents

Description

P. F. SARRON AND J. SIMON.

ELECROCONVEHTER FUBNAQE APPLICATION HLED )UME Il. 1018.

1,325,1 14. Patentedl Dec. 1919,

2j Fre s VIE- wml/N JLM JM@ APAUL FEANGOIS SABBGN AND JULES SIMON, OF LYON, FRANCE.

ELECTROCON'VEBTER-FUBNACE.

Specication of Letters latent.

Patented Dec. 16, 1919,

ppeatiom led June 8, 1918. Serial No. 238,899.

Toy al'wom concern.- i Be it known that we, PAUL Fnanols San- Vnon: and .lunas Sinon, citizens of the French Republic, both of Lyon, France, have invented certain new and useful Improvements in Electroconverter Furnaces, of which the following specification.

. E; This invention rela to improvements 1n' electro-converter furnaces and process of treatment for the manufacture of ordinary and special steels thereby.

.By the invention furnaces known as converters can be re idly transformed into electric fulrnaces,b(wl11ich alloig's'the aivant cu iarto t types o appara ils to baegiiilled and a special operative method to be performed for the economical manufacture of the best steels, by treating more or less pure products and freeing, if necessary the metal obtained from the greater art of the which are found dissolved terein.

-T e following description relates by way of example to an acid converter with lateral blast, transformed into an electric furnace with two electrodes.V

In the annexed drawings:

Figure 1 is a vertical section through the axis 1-1 of the furnace placed in the horizontal position and arranged for working as electric furnace;

Fig 2 is a vertical section on line 2 2 of Flg. 3; Fig. 3 is of Fig. 1; A

4Fig. 4 is a vertical section through the axis 1--1 of the furnace, but plpced in an upright position and arranged for working as converter; A i Fi 5 an elevation on a smaller scale of the'w o le structure forming the furnace, its electrodes, the suspension cables, the cab of the regulating devices and the traveling bri e supportin this cab.-

a horizontal section on line 3 3 F1 6 1s a vertical section of the nsulating evice for an electrode for` a furnace mg dish .imag i' 'd ai 1m mg 1i f e outer a an e o 'the applaratus are provided openings which, e apparatus works as converter, are closed by p ills c of a compoeitionidentical with or srm ar to that o th-lining, the cover ,d'is then open in the position illustrated in Fig. 4.

In order to transform the apparatus into .an electric furnace, it is brought into the horizontal position and the plugs are rel-noved by means ofthe rings e; then the openings can be used for eil'ectin the chargmg of the apparatus, althou h t can also be effected t rough the nozz e f. This done, metal sleeves g are then inserted into the plug o enings and fixed to the furnace plates y means of any suitable keying means; it is in these sleeves, which may be cooled or not b a circulation of air or water, that the e ectrodes h slide, suspended by the cables which may be provided with automatic regulatin devices. These apparatos which raise orower the electrodes and their electric connections are preferably arranged in a cab j shown in Fig. 5 supported on Aa traveling bridge Ic which can move above the furnace and the flue l. The cur- A rent is conveyed to the electrodes by the iexible conductors m, the bars n and the metal jaws o fixed closely en the electrodes by means of the vbolts p.` These jaws are guided by metal rods g` "integral with the sleeves g and carr at their upper part abutinent screws 1'. T lis device secures the guiding o'f the electrodes when the furnace 1s inchned for the washings which are effected through the nozzle the ta ping of the metal being prefera y electe through the channel s, plugged normally by the refractor` plug t. The tappintgh is thus eliected wit out havin to inc ine e apparatus.

When it is esired to withdraw the electrodes from the furnace they areraised until the jaws abut against the nuts r; at that moment the end u-of the electrodes, which is found to be the hottest, has engaged in the socket end 'v of the sleeve g the electrodes are removed from the muflies and the cables 'i continue to be pulled; the sleeves then accompany the electrodes, protecting them from the action of the air, while the bridge la transports them over and lowers them4 into another furnace or -into heat retaining devices comprising cylinders lined with refractory material mwhich they can remain until again required for use.4

,The general arrangement, which has just been described by way of example, can be applied to any converter other than an acid converter with lateral blast; the blast can be effected through the bottom or in any manner whatever, but in all cases the air-,chamber is provided with a tube w, with slidingvalve y, connected to a suctionmachine 'top electrodes and one or more `ductive sole.

capable of producing a relative vacuum in the apparatus, after it has been closed as hermetically as possible b means of 4the plugs c and the lid d, whic latter need not e lntegral with the apparatus and can be constructed like a digester stopper.

The lining may be neutral or basic; in the latter case the electrodes are notV in direct contact with the sleeves g. In order to pievent the current passing into these sleeves from being'diverted to the manesian lining which becomes conductive at igh temperature, a refractory packing z formed of a bad conductor is interposed between the electrode and the sleeve as illustrated in `Fig. 6.

The furnace may be an arc furnace, with or without magnetic blast, or may have an arc and resistance combined comprising either only the top electrodes, or one or more lar masses embedded in that part of the ining which forms the sole, or finally one or more top electrodes and a wholly or partiall con- It is evident that suitab e electric insulation must correspond to each particular case; precautions are also to be taken for avoiding the closing of the magnetic circuits and to hinder the production of Foun cault currents.

Further, the upper electrodes can also be suspcndedfrom posts placed beside the furnace, near the operating devices.

These electrodes can moreover be rotected by the known means such as jac ets of sheet-steel, facings of silicate of sodaJ and asbestos held in place *by a metal grating, etc.

The eneral method for the manufacture of stee starting from any suitable materials, is as follows:

In the first place two electro-converter furnaces are disposed, one with acid lining, the other with basic lining. In the former the fusion of the material, cast-iron, lin of cast-iron or steel, dross, etc., is eecte If the products to be melted do not contain much carbon some carbon is added to the charge in order that the melted product may form a casting; also, if necessary, the deaired additions are made so that this castin contains a proportion of silicium whic makes it suitable to be converted on an acid lining. When the fusion is terminated, the apparatus is brought into the converting position andthe blast is operated until the greater part of the silicon is oxidized; at this moment the bath has become very hot; the blast is stopped and the metal is run into a heated pocket which is emptied into the electro-converter basic furnace which has been reviousl charged with the lime reqiir for dep iosphorization; then the conf version is terminated. At the end of the superblowing the greater part of the phosphorus is burnt, but there still remains too much of it in the metal to allowr the latter to form a good steel; it is also necessary to sub- ]ect it to an 'electric super-refining which will, besides, serve for the elimination of the sulfur. For the pu ose it is washed after the superlblowin p an before removing the plugs e the lid is turned down on to the nozzle. vAll the openings are seen to be well closed and the suction machine is started working, after havi opened the valve o; a relative vacuum suus created above the bath and the excess of s dissolved in the metal is eliminated w ich greatly 'contributes to improve the final product. This being done, the electrodes are put into place, after having inserted the materials necessar for the formation of a new basic slag an the current is turned on; the amount of scale is relatively slight, because a part of the oxid of iron which has formed in the course of the su er-blowi serves to oxidize the impurities eft in thiinath. The washing is repeated and the refining of the metal terminated in the usual manner.

This general method enables steels of superior quality to be manufactured from any products, much more quickly than in the Martin r the electric furnace; the operation is simplified if one has well defined products at disposal, if, for instance, they contain for example very little phosphorus and sulfur they can belreatcd solel in an acid electro-conveis'terifurnaee, whic eiects the fusion of the materials, the conversion, the elimination of the dissolved ses and the fusion of the added matters, w iich last may be as considerable as desired. If the products which are to be treated contain much phosphorus they are treated only in a basic electro-converter furnace, which effects the fusion, the conversion, the elimination of the dissolved gases and the electric super-refint is evident that this process a plies equally well to liquid castings prep eutside the electro-converter furnace and coin-- ing from a' blast-furnace, a smelting-furnace or other apparatus; these castings are treated, according to their chemical composition, either only iny an acid electro-converter furnace, oronly in a basic electroconvcrter furnace, or, by means of fractional conversion iirstin an acid electro-converter furnace, then in a basic electro-converter 1'6 as in the ordinary electric furnaces.

The process of manufacture is rapid and economical, as the refining is almost wholly elected in a-few minutes and -without'the necessity of heating the metal. The economy l is alsodue to the fact-that carbureted materalils aire' treated gltxich melt at a comparativ ow tempe ure, in an a araus whic -has been .left by `the"precedfig operation at a very hi h temperature in t art due-to the exot rmcreactionsw 'ch ave been effected during the conversion. The amount of heat to be electrically furnished is therefore relatively slight.

Further, the electro-converter furnaces so canbe almost hermetically closed,y o to their method of construction; it is there ore possible to Vcreate therein a relative vacuum, whichV enables the greater art of the contained in the metal to eliminate What we'hclaim as our invention and desire 12o-secure by Letters Patent of the United States is: I 1. An electroconverter furnace comprismgsaid rods fixed to said sleevesy and ing a casing of the converter type, a cover therefor? a refractory lining for said casing, said casing and linin bein openings, sleeves fitte in sai openings, removable electrodes sleeves and slidable erein, means or conveying current to said electrodes, means for suspending and effecting the sliding movement of said electrodes and for removing them from said sleeves and plugs for closopenings when said electrodes are removed from said sleeves.

2. An electroconverter furnace comprising a casing -of the converter type, a covei` therefor2 a refractory lining for said casing, Said casing and lining being provided with openings, sleeves fitted in said openin s, means for cooling said sleeves, lectro es passing throu h said sleeves an `slidable therein, jaws ed on said electrodes,I metal aing through said jaws, bars lixed to sald electrodes flexible electric conductors attached to said bars, means for suspending and effecting the sliding movement of said electrodes and for `removing them from said sleeves, and plugsfor closing said openings when said electrodes are removed from sald sleeves In witnesswhereof we have signed this specification in the presence of two wit- ,AUL FRANQOIS SARROPI v ES SMON. Witnesses:

Jaan GERMAIN, GRADI Coanrrr.

rovided with' assing throu h said

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