CA1088758A - Plant for and method of electroslag remelting of metals and alloys - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

A plant for electroslag remelting of metals and alloys, according to the invention, comprises a cooled mould mounted on a cooled base plate where a slag bath is arranged.
Introduced into the slag bath is one end of a consumable electrode, its other end being connected to one of the poles of a current supply source. The plant has at least a single non-consumable electrode that is connected to another pole of the current supply source in series with the consumable electrode. The disclosure also teaches a method of electro-slag remelting of metals and alloys in which an electric current is passed through the consumable electrode, slag bath and non-consumable electrode during the remelting process.

Description

1(~88~58 ~TL~ FOR ~l~D l~HOD O~ C~R9SLAG L~I~ir~ G
O~ ~i~VllAIS ~LTD AILOYS
rrhe -present invention relates to pl~lts ~or and me~thods olD elec-trosla~ remelti1lg olD Irletals and allo~s. It is partic~-larly use~ul lor producing ingots and slag ingots ~or subse-quen-t metallurgical collversion and for manufac-turing sound shaped cas-tings ~or machine-building indus-tr~, sai~ castings being less expensive than welded-and-~`orged or extruded-and--welded struc-tures and being not onl-~ not inferior in terms of their qualit~ but on certain occasions even superior to those.
In many industriall~ developed coun-tries o~ the world the engineering and technology o~ electIoslag remelting o~
metals and alloys are s-triding vigorously.
~ his has created a problem o~ providing such plants and methods which would o~fer, ~irstly, a higher e~iciency, that -is heretofore low on prior-art installations, along wit~ a high qualit~ of metal, and would enable, secondly, the produc-tion of various products: ingots, slab ingots, shaped cast- -ings, tubes, tube skelps, etc., on -the same e~uipment and1 thirdly, t~1e-y would allow simpli~ying bot`n the ~aintenance a~d operation o~ metallurgical equipment~
At present known in the art is a pl~rlt ~or electroslag - remelting o~ metals in a cooled rnould with two consumable electrodes or two groups of consumable~etrodes comlected in seriss to an electric circuit. Both consumable electrodes or . .

.: . ~ ' ~088758 'ooth groul)s oi` consui~a'ole ~lec-tL~des are mounted in a ~ingle electrode holder, `oeing carried vertically at t~-le same rate by ole cor~lon vertical -tr~ls~er gear. Now said plant is em-plo~ed 'or roducin~ slab ingots.
Hcwever, the above plan-t is no-t deprived of di~advantag-es, of which tihe main consists in that it is unfeasi'ole for producing hollow shaped castings with projecting parts, a ~eature liL~ii-ting the field o~ its applica-tion. iiloreover, said pla~t ~ails -to avoid considerable heat losses in the slag bath owing to high-rate cooling of -the mould in the slag bath zone.
Also k~own in the art is an installation for alectroslag remelting o~ metals and alloys, comprising an auxiliar~ ele-ctrode for sustaining the requisite tempera-ture of liquid slag a~d metal in a mould at the instan-t when a new electro-de is fitted upon melting the proceding one.
However, at the above installation said auxiliar~ ele-ctrode operates only at short-time duty during -the replace-ment o~ the melted consw~ble electIode, whilst its applica-tion in said installation complicates both its design and attendance. Moreover, in view o~ interruption in the electro-slag remelting process needed to replace the consumable ele-ctrode, an ingot sur~ace is rough and, i~spite of the auxi-liary elect~ode operating during the replacement period, it adversely a~ects the quality of metal obtained.

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~ lOWIl as well ill the art is a l~ethod oi elect~oslag re-meltillg o~ etals ancl alloys in which an electric current is fed t~ough a consumable electm de ~nd slag to a copper mouldc ~he above method intensifies -the melting of the electrode, i.e. provides a higher elficiency o~ the elec~ro lag remelt-ing process~
However, said method suffers from a serious disadvan-tage which resides in electrolytic attack on the working sur-face of the copper mould and its erosion owing to the passage of the electric current from the consumable electrode through the slag to the mould which causes rapid failure of the lat-ter (mould).
~ lso known in the art is a plant for producing hollow -metal ingots by the electroslag remelting technique, wherein said hollow ingot is shaped by a mould and a mandrel5 a power supply source being connected to said l~andrel and to a consu-mable electrode. In service an electric current is passed through the consumable electrode, a slag ba-th and -the mandreL
A disadvantage of said plant lies in rapid failure of the mandrel owing to electrolytic deterioration and erosion of the mandrel surface caused by the passage of the electric current through the slag and said mandrel.
Enown in the art is a method of the electroslag remelt-ing o~ a consumable electrode in a cooled mould by carrying both the electrode and the mould during said remelting to provide -the socalled method with an opposite motion of an . , .

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_ 1,1. _ electrode and mould. With sai~ ~ethod the cross-section oiR
the con~umable elec-trode ~ust be smaller tllan -that of an ingot being melted, the height o~ the melted ingot being therefore always smaller -than the length of -the consumable electrode. ~ome-times, particularly v~nen producing tube skelps and slab ingots the cas-tings being melted must have a consi-derable heigh-t. However, the above method fails to provide such castings.
Also known in -the art is a plant for producing ingots in metal allo~s, especially in steel, by the elec-troslag re-melting technique, said plant comprising a mould whose bot-tom part determines external dimensions of an ing~ot being moulded, said bottom mould part passing into a flaring, pre-ferably, conical intermediate part which in turn Fasses into a spreading out top part. ~oth the mould and the ingot move -relative to each o-ther. Said plan-t is superior to -the prior--o~e~s in that it is adaptable for remel-ting electrodes with a cross-section greater -than that o~ the ingot being melted-However, said plant suffers from a low efficiency and fa~s to produce shaped castings with projecting parts. ~he flared -top part o~ the mould serves either as a collector of liquid slag and metal or as a bath for melting metal and increases the cooled surface of the mould walls coming in contact with the mol-ten slag bath during electroslag remelt-ing, which in turn increases heat reinoval from the slag bath diminishing thereby the plant efiiciency.

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-" 1088758 1'~nV~Jn as well is a r~ t ~or electrosla~ neltir)~ ofshaped cas-tin~s with concurrent ~usin~ OI cer-bain ii~emberS~
said plan-t co~prisin~ a ~ould mounted on a bass plate with an openin~, into which a member beiIlg fused is introduced, and an electric current switch with connects one of the po-les of a power supply source either to the mould or to a consumable electrode.
A disad~antage of said plant resides in that as &n ele-ctric current passes throug~ the ~ould and fused member, power losses are -too high owing to slag accretions built-up on the working surface of the mould; moreover, mould walls and a base plate can break down upon spreading of a i~etal pool &nd making an electric 'imould-fused member" circuit by said metal pool.
~ he main object of the presen-t invention is to overcome the aoove disadvantages peculiar to prior-ar-t pl~l-ts and methods of electroslag remelting oP metals and alloys.
A~o-ther object of the invention is -to provide a plant for &~d a method of electroslag remeltin~ of metals &nd al-loys which would o~fer not onl~ a considerably higher effi-ciency, as compared with the prior-ar-t plants of the t~pe described, but would allow producing various pro~ucts on the same plant, i.e~ would extend the ~ield of application of the electroslag remelting facilities and si~plify concurren-tl~ both the mainten&nce al~d operation of said pla-nt.

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~ aid aLl~ o-ther obj C-C-G5 are achieved iLl a Qlant l`or ele-ctroslag rer~ltinO ol ~letals a~d ~lloys, co~,rising a slag bath contained in a cooled mould set u~ on a base plate, with ~the bottom end o~ a consu~able electrode bein~ submerged in-to said slag bath, said electrode being co~1ected -to o-ne of the poles of an electric current supply source ~ld beirlg carried by a vertical traasfer gear, said pl~nt, according to the irverltio~, comprising a-t least one non-cons~nable ele-ctrode co~ ected to the o-ther pole of the electric current supply source in series with the co~sumable electrode, the non-consumable electrode and base plate being movable rela-tive to each o-ther in a vertical direction.
; ~he application of said plant accelerates the melting o~ the coIlslLmable electrode with -the same power input, in other words, a higher plan-t efficiency and b~tter qualit~ of an ingot are provided owing to ~ore efficient an/complete utilization o~ heat power of the slag bath. Moreover, this eliminates the necessity ~or dumr4y bars which are unavoidable in prior-art plallts~ this si~lplifying the elec-troslag remelt-ing techn;que and providing a be-tter design of the base plate~
Xelative advance of the non-consu~able electrode and base plate can be effected since the non-consumable electrode-is fitted with a vertical transfer gear, or the base plate can be provided with a gear for vertical transfer of the ingot bei~g melted. In this case the non-consu~able electrQde and the mould are immovahle during the electroslag remelti~g . ,~

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-~ ~08~758 process ~vhich siIlpli~ies both -the main-tenance and operation o~` the plarlt.
~ he non-consumable electrode is advisable to be made hollow, fixed on asl interrlal wall of the mould and insulated electrically there~rom, while the consumable elec-trode must bearranged inside the non-consumable one and i~mersed with its bottom end in the slag bath; it is expedient that the mould and non-consumable electrode be carried upwards by one vertical tra~is~er gear, the ingot remaining sta-tionary.
Said plant is well adaptable for e~fecting the method b~sed on an opposite motion of a consumable elec-trode and a mould, the plan-t ef~iciency being in this case considerably higher than in prior-art installations owing to a rational electric circuitry e~lployed for connecting both the consuma- -ble and non-consumable electrodes -to the power supply source and because the hollow non-consumable electrode ~ed into the slag bath acts at the same time as a heat-insulating element, dirninishing heat losses o~ the slag bath owing to heat trans- -~er to the rnould wall, insofar as said wall happens to be heat-insulated by the non-coilsuTmable electrode.
The base plate can be equipped ~ th a gear ~or vertical -~trans~er o~ the ingot being melted, the mould and non-consu-mable electrode being stationary in that case.
Sornetimes it is convenient in terms of design to make t~e non-consumable electrode as current-carrying pla-tes en-1~887S8 colnpassial~ tne consun~ble electrode, said non-consumable elec-trode (plates) being moul~ed on the in-te~nal surI'ace of the mould and insulated e~ ctrically therei`rom.
~ he current-carryiIlg plates can 'be set up alon~ the entire perirleter of the internal mould surface.
~ he noll-consuma'ole electrode can be rnade hollo~s, a man-drel being fixed therein and insulated electricall~7 there-from, the consumable electrode in this case encompassing at least partly the non-consumable one and being submerged with its bottom end into the slag bath, the non-consumable ele-ctrode, mandrel and mould are advisable to be carried up-wards by one vertical transfer gear ensuring the production of a hollo-7l casting. -' ~ he proposed plant makes it possible to produce tube skelps ~yelectroslag remelting of metals and alloys, hea-t losses of the sl'ag bath owing to heat transfer -to -the mandrel-diminishing in this case as the mandrel happens to be heat--insulated by the non-consumable electrode.
~ he base pl~-te can be fitted with a vertical -transfer gear for carrying -the melted tube skelp.
~ o produce a hollow casting with a bottom the plant for `
electroslag remelting of metals and allo~7s, according to the invention is advisable to be fitted with a current s~tch connected from one side to one of the poles of the current supply source and from the other to the base plate or to the non-consumable electrode.

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_ g _ Such an embodiment makes it possible at the initial mome~t, whe~ melti~g the bottom o~ a preset thickness, to operate on the proposed plant according to a co~ventional circuit passing`an electric current through the consumable electrode, slag bath, ingot and the base plate.
It is sound practice, when producing -tube skelps on the plant ~or electroslag remel-ti~ of mstals a~d alloys, that the non-consumable electrode be made as two hollow rods of any desirable cross-section, concentric with each other, one of said rods accommodating the mandrel i~sulated electrically therefrom and the other rod bei~g disposed on the internal `-surface of the mould and bei~g also insulated ~lectrically therefrom, the consumable electrode that is made hollow being advisable to be set up intermediate of the hollow rods, con-ce~tric therewith and submerged with its bottom end into the slag bath, the non-consumable electrode and the mould being carried upwards by one vertical tranafer gear relative to the melted tube skelp.
Such a plant enables the production of diversi~ied hol-low castings and is noted for low heat losses o~ its slag bath owing to the no~-consumable electrode insulating thermal-ly said slag bath ~rom both the cooled mould walls and the mandrel, a ~eature which enhances the plant ef~iciency.
On said pl~nt -the base plate can be equipped with a gear for vertical transfer of the melted tube skelp.

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. - ' 1(~887S8 In case a plant for elec-troslag remelting of metals and alloys is furnished with a base plate having an opening whe-rein a member, being fused, is fed, and with a curren-t switch connected from one side to o~e of the poles of the current supply source and from the other tv the fused member or con-sumable electrode, said plant is adapted f~r produci~g shaped castings by the electroslag remelting tecimique with concur-rent fusing of certain parts, ensuring a guar~nteed quality of joining the member being fused with a casting body.
~ he above plant provided with the current switch co~ne-cted from one side -~o one of -the poles of the current supply source and from the other to the consumable electrode or base plate enables the consumable el~ctrodes to be replaced in the course o~ electroslag remelting, providing sound castingsO
It is expedient that in said plant ~or electroslag re-melting of metals and alloys the no~-consumabls electrode be made of graphite.
Graphite is a good conduc-tor of electricity, i-t features a high heat resistance and owing to its great affinity to oxy~en it is a good deoxidizer during electroslag remelting, this being especially important when remelting steels con-taining such easily o~idizable eleme~ts as titanium, silicon aluminum, etc.
~ he method of electroslag remelting of metals and alloys on the proposed plant, according to the invention, consists in that during the entire alectroslag remelting process an -, ~ ~. ' - - -,', . ' .' - ~ ~

---`` 10887S8 electric c~rre.r.t is passed through a consumable electrode, slag~ bath alld non-consumable electrode.
It is good practice if during the entire electroslag remelting process the non-consumable electrode is carried upwards b~ the vertical trans~er gear at a rate equal to that o~ motion of the slag bath, keeping thereby the end o~ the -non-consumable electrode submerged into the slag bath, with the consumable electrode being carried downwards, as it melts,~
to obtain an ingot of remelted metal.
In case the plant for electroslag remelting o~ metals and alloys comprises a base plate fitted with a vertical transfer gear, the ingot set up on said base plate is carried .
downwards, as it is being built up, so that the level of said slag bath remains stant relative to a stationary non-consuma-ble electrode and mould.
If the plant ~or electroslag remelting of metals and allogs employs a hollow non-consumable electrode fi~ed on the-internal surface of a mould, according to the in~ention, said .
non-consumable electrode is carried u~wards together with the mould by one vertical transfer gear with respect to the ingot bein$ melted, realizing thereby an electroslag remelting method with an opposite motion of the mould and consumable electrode.
In case the.plant is fitted with a gear for vertical transfer of a base plate, the ingot being melted is carried 10~87S8 downwar~s by said vertical transIer gear, a non-consumable electrode and a mould being immovable in this case.
According to the invention, to produce on said plant for electroslag remelting o~ metals and alloys a tube skelp the no~-consumable electrode is carried upwardæ by ~he verti-cal tran~fer gear together with the mandrel, the tube skelp being immovable.
When moulding a tube skelp on a plant with a base pla-te provided with a vertical transfer gear, said tube skelp is carried downwards, a non-consumable electrode, ma~drel and mould being stationary ~o that the level o~` a slag bath is kept constant ensuring the shaping of the tube skelp. -~
~ or producing by the method of the invention an ingot of remelted metal with a greater length than that of the melted electrode, the consumable elec-trode, non-consumable electrode and the mould are transferred upwards, the consumable electro- -de being carri.ed at a rate o~ 0.05 - 0.95 the rate o~ motion of the slag bath whilts the non-cons~mable electrode and the mould travel at a rate of transfer o~ said slag bath, mainta-ining the ends of both the consumable and no~-consumable ele-ctrodes immersed in the slag bath.
From the equality o~ volumes of remel~ed electrode metal -and that obtainable upon remelti~g it ~ollows that the height of the melted ingot will be as much greater than the length of the consumable electrode, as the cross-section o~ said consumable electrode is greater than that o~ the melted ingot, , .. , . . - ~

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i.e. l2sl1 = S1 S2, where 12 and 11 is -the length accor~ingly of the in~ot being melted and consumabl~ ~lectrode, and S2 and S~ - their cross-sec-tions.
By selecting the ratio S2:S1 within (0.95 - C 05) the rate of transfer of -the coils~nable electrode, i.e. the ele-ctrode melting ra-te will vary within (0.05 - 0.95) of the slag bath transfer, i.e. of the ingot building-up rate.
Thus, by choosing consumable electrodes of appropriate cross-section and leng-ths it is possible to obtain the melt-ed ingot of a maxi~um height. l~oreover, the use of low-height electrodes with large cross-sections decreases power consu-mption owing to a lower electric resistance of the consuma-ble electrode.
If the plant is provided with a gear for vertical trans-~er o~ a base plate, then, according to the invention, said gear carries an ingot downwards so that the level of a slag bat~ is kept constant relative to a stationary non-consumable~
electrode and mould, with a consumable electrode being car-ried downwards, as it melts.
To enable the production of ingots of a still greater height according to the invention, from the beginning of the remelting process t~e ingot is carried downwards by the ver-tical trans~er gear -to an exte~t of possible gear transfer so that the level of the slag bath is constant with respect to the immovable ~on-consumable electrode and mould, the oonsumable electrode of a cross-section ($1~ greater than -, . . . . - .
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108~758 that (S2) of -the l1lelted ingo-t ~eing carried downwards, as said conswnable electrodes melts, whereupon the gear discon--tinues the ingo-t transfer and up to the end of the re~lelting process the consumable electrods, non-consumable electrode and the mould are carried upwards, the consumable electrode being moved at a rate of 0.05 - 0.95 the rate of the slag bath, whilst the non-consumable electrode and mould travel at a rate of transfer of the slag ba-th, keeping the ends of both -the consumable and non-consumable electrodes submerged into the slag bath and ensuring the production of the ingot superior in height to a plant mas-t.
~ o produce a tube skelp with a wall -thickness smaller than the cross-section of the remelted electrode, according to the învention, the consumable and non-consumable electro- ~-des, mould and mandrel are carried upwards, the consumable electrode being transferred at a rate of 0.05 - 0.95 the rate -of the slag bath, whilst the non-consumable electrode, mould .. .
and the mandrel are shifted at a rate of the slag bath, with the ends of both the consumable and non-consumable electrodes being i~mersed in said slag bath~
In case the plant comprises a gear for vertical transfer of a base plate, -then, according to the iIlvention, said gear .:.
is employed for carr~ing the tube skelp downwards so that the level of a slag bath remains constant relative to an immova-ble non-consumable electrode, mould and mandrel, the consu-- .

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~088758 ~ 17 mable elec-t-rode wi-th a c~oss-sec-tional area (S1) greater than that (S2) of the mel-ted -tube skelp being carried downwards, as said consumable electrode Inelts~ keeping the ends of bot~
the consurJIQble and non-consumable electrodes immersed in the slag bath and ensuring the production OL -the tube skelp with the wall s~aller in thickness than the cross-section of the remel-ted electrode.
'~o enable the manufacture of` a tube skelp superior in height to the plant mast, according to the i.-nvention, from the beginning of the remeltin~ process the vertical transfer gear carries the tube skelp being melted ~ownwards so that the level of the slag bath is kept constan-t relative to the immovable non-consumable electrode, mould and mandrel, with said consumable electrode ha~ing a cross-sectional area ~S1) greater than that (S2) of the melted tube skelp being trans-ferred downwards, as said electrode melts, whereupon ~urther trans~er of the tube skelp is discontinued, the consumable electrode be:ing trans~erred up to -the end of the process at a rate of 0005 - 0.95 the rate of the slag bath, whilst the non-consumable electrode,mould and mandrel are shifted at a rate of the slag bath, with -the ends of both the consumable and non-consumable electrodes being immersed in said slag bath.
When producing hollow shaped castings ~.vith a bottom by the method of the invention at first -the consu~able electrode is remelted by passing an electric curren-t -through said ele-.

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ctrode, tlle slag b~th. all~ base plate with -the non-co~lsumable elec~ro~e, ~i.andrel and mould being i~J~ovable until -the bot-to~ ol` a ~iven thick-ness is built-up and un-til the end of the consumable elec-trode submerges into -the slag bath, vlhe-reupon and up to the end of the process the currer~t is passed tl~ou~h the consumable electrode, slag bath and non-consuma- ~:
ble electrode, the mandrel and the non-consumable electIode ~-being carried upwards a-t a rate e~ual to tha~ o~ the slag ~ -b~th, sustaining the end of the non-consumable electrode in ..
said slag bath and moulding the interior of -the casting being melted. .......
~ or producing hollow castings by using a movable mould, upon moulding the bottom of a given thickness, both the man- -drel and non-consumable electrode are transferred together wit~ the mould by one vertical trans~er gear.
If the pl~nt is fitted with a gear for vertical trans~er of the base plate, then. upon moulding the bottom, the hollow casting is carried downwards b~ said vertical transfer gear relative to the ir~movable mandrel, non-consumable electrode and ~ld.
It is expedient that during electroslag remelting of metala and alloys, according to the inventioIl, upon melting . -.
of one consumable electrode the curre~t supply.source be -~.
discor~Lected from the consumable electrode and connected to . .: -the base plate to maintain the slag bat~ in hot ~luid state, - ..
whereupon the melted consumable electrode is replaced~ with ~:

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`-` 1088758 the end of said new consuinable ~l~ctrode bein~ qubmer~ed into the slag ba-th, said consumable electrode is a~ain con-.nected to th- current supply source aLld electrosla~ remeltirlg o~ said i-le~ corisumable elac-trode continues.
Thus, a plu~alit~ of low-heigh-t consumable electrodes can be remelted one after another in-to heavy i~gots. This is converlient and profitable for the manufacturing of consuma-ble electrodes and enables the arrangeme~t o~ an electroslag remelting plant in the premises of a limited height, this being of prime importance when organizing a new p~oduction.
In electroslag remelting o~ metals and alloys it is sound practice, according to the invelltion, upon establishing a slag bath -to pass an electric current through a non-consuma-ble electrode, slag bath and a fused member until the top end ~ace of said fused member starts melting, with a consu-mable electrode being withdra~m from the slag bath to be t~e-reupo~l submerged with its end in-to said slag bath, following ~ich the electric currerlt is passed throu~h the consumable elec~Dde, slag bath and non-consumable electrode un-til the --completion of the electroslag remelting process, er~suring a :.
guaranteed jointing of the ~used member to a casti~g body.
The nature o~ the in~ention will be clear from the fol- ~ :
lowing detailed description OI` particular embodiments of a plant for and a method of electroslag remelti~g of metals and alloys to be had in conjunction with accompanyingd draw- .-ing, in which-, .. ,. , . . ~. .: . :

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.~ . - , ~088758 Fig. 1 shows a plarlt Yor electroslag rel~lelting of metals and alloys;
~ ig. 2 depic-ts a plant for electroslag remelting of me-tals and alloys with an ingot vertical transfer gear;
Fig. 3 represents a plant for electroslag remelting of metals and alloys with a consumable electrode set up on an internal surface of a mould;
Fig. 4 shows -the same plant with the ingot ~ertical transfer gear;
Fig. 5 - section V-V of Fig. 3;
Fig. 6 shows a possible embodiment of the consumable electrode;
Fig. 7 depicts a plant with a mould flaring in its top portion and an insertion piece shaped as a non-consumable electrode;
Fig. 8 - section VIII-VXII of Fig. 7;
Fig. 9 - section IX - IX of Fig. 7;
Fig. ~0 illustrates the calculation of the rate of trans- ~ --fer of a consumable electrode;
Fig. 11 illustrates the operation of the plant, as shown in Fig. 7 and fitted with an ingot vertical transfer gear;
Fig. 12 shows a plant for electroslag remelting of metals and alloys while producing a tube skelp, said plant being provided with a non-consumable electrode and a mandrel intro~
duced therein; - -. - . - .
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Fig. 13 - section XIII-XIII of ~ig. 12;
Fig. 14 shows an embodiment of the non-consumable ele-ctrode;
Fig. 15 illustrates the operation of a plant for ele-ctroslag remelting of metals and alloJs, as shown in ~ig. 12, with a tube skelp vertical transfer gear;
Fig. 16 depicts a plant for electroslag remelting of me-tals and alloys while producing a tube skelp by using a non--consumable electrode set up on a mandrel and a mould;
~ ig. 17 illustrates the operation of the plant shown in Fig 16 and fitted with a tube skelp vertical transfer gear;
~ ig. 18 shows a part of the plant illustrating its func-ti~ng with a mould ~laring and a mandrel narrowing in their -top portions; -~ ig. 19 - section XIX-XIX of ~ig. 18;
~ ig. 20 - section ~X-XX of ~ig. 18;
Fig. 21 illustrates operation o~` a pla~t, as shown in ~ig. 18, provided with a tube skelp vertical transfer gear;
~ ig. 22 depicts a plant for electroslag remel-ting of metals and allo~s while producing a hollow casting wi-th a bottom in it8 lower portion, said plant having a movable external mould; ~ -~ ig. 23 s~ows a plant for electroslag remelting of me-tals and alloys while producing a hollow casting with a bot-tom in its lower por-tion, said plant having a base plant ~ -movin downwards;
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-- CO _ ~ . 24 shows relative posi-tion o~ -tlle ~arts o~ a plan-t for electroslag remel-ti~O of me-tals and alloys a-t ~the begin-ning of the process o~ producing a hollow shaped cas-ting ~ith a bottom iIl its lower portion;
Fig. 25 shows relative position of the parts of a plant for electroslag remelting of metals and alloys at the end of the process o~ manufacturing a hollow shaped cas-ting with a bottom in its lower portion;
~ ig. 26 depicts a plant ~or electroslag rernelting of metals and alloys at the moment of replac~ment OI' a consuma- ~
ble electrode; :
Fig. 27 shows relative posi-tion OI` plant parts upon melt- -ing several low-height consumable electrodes with a descend-ing ingot; -Fig. 28 shows relative position of plant parts at the begi~ning of -the electroslag remelting process with concur-rent fusing of a member;
Fig. 29 shows relative position of the plant parts upon .
fusing æaid member~
Fig. 30 shows relative positio~ of -the plant parts upon fusi~g said~member and remelting a plurality o~ consumable eleotrodes with a descending ingot. , Conaidered hereinbelow are several sxamples illustrating the application of the present invention while:
a) producing ingotæ;
b) producing tube skelps;
,~
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' ~ - , ~ . - . -: '-: .. ' ,- ~- ., .: .

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1088~S8 c) producing hollow castings with a bottom;
d) replacing~ consumable electrodes durin~ melting;
e) producing castings with concurren-t ~usi~g of cer-tain me~bers.
A plant for electroslag remelting o~ me-tals and alloys comprises a bearin~ mast 1 (~'ig. 1) and a top carriage 2 travelling -the realong, said carriage 2 mounting an electrode holder 3 with a consumable electrode 4 ~ixed therein. ~o shape an e~ternal surface of ingots use is ~ade of a cooled mould 5 set up on a cooled base plate 6. Prior -to the begin- ~ -ning of the electroslag remelting process a slag bath 7 is established in the mould 5 (molte~ slag starti~b~)~ the con- -sumable electrode 4 a~d a non-consumable electrode 8 being submerged into said slag bath 7. ~he non-consumable elec-trode 8 is secured by means of a stand 9 to a bo-t-tom carria~e 10 mounted on the mast 1 and adapted for vertical -transfer of said non-consumable electrode 8 along the mast i. ~oth the consumable electrode 4 and non-consumable electrode 8 are connected to unlike poles of an a.c. supply source ~, an electric current passing thereb~ -through the consumable ele-ctrode 4. slag bath 7 and non-consumabla electrode 8. lo ena-~ble the ends o~ the consumable electrode 4 a~d non-consumable electrode 8 to be always ;~mersed in the slag bath 7 during the entire electroslag remel-ting~ process the non-consumable electrode 8 is transferred upwards a-t a rate equal to that .
~ of tne slag bath 7, whilst the consumable electrode 4 is lo--, .
~ wered into said slag bath 7, as it melts.

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~088758 An in~ot 12 beinO ~ lted is s~laped by the base i~late 6 a~d mould 5. 'L'O ,preclude the passage of tl--e electric curren~
to an in-ternal wall 13 o~ -the mould 5 'both -the consumable ele-ctrode 4 and non-consumable electrode 8 are not electrically associated with t11e mould 5, said mould 5 together with the base plate 6 bein~ not co~nec-ted into t..,he electric circuit.
Insofar as the mould 5 and base plate 6 are d~ad, their walls are therefore protected against electrochemical attack.
Ic case the plan-t base plate 6 (~ig. 2) is fitted wi-th a ' gear 14 for vertical -transfer of -the ingo-t 12, there is no need to carry the non-consumable electrode ~. In this case the vertical transfer gear 14 carries the ingot 12 downwards, as it is built up, so that the level of the slag bath 7 is kept constant wi-th respect to tne irnmovable non-consumable electrode 8 and mould 5~ , Said plant is more collvenient in service because the mould is stationary during -the melting process, however, it ~' requires a ver-tical shaft for its arrangernen-t ~vith a depth sufficient to accommodate the melted ingot 12.
Fig. 3 shows a plan-t ~or electroslag remelting of metals and alloys in which a non-consumable elec-trode 15 is made hollow and is rigidly ~'ixed on the in-ternal wall 13 of a mould 16 having a low height as compared with -the above plant. To preclude the passage of an electric current to the m~uld 16 a l~yer 17 of electric insulation is placed between the non-consumable electrode 15 a~d mould 16.

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O~in~ tv said desi~n tl~e low-height mould 16 can be used for producinJ in~ots 12 oi` considexable height ~ecause bo-th the mould 16 and non-consurnable electrode 15 are carried up-~ards b~r one vertical transfer O~ear 10.
In operation -the non-cons~-nable electrode 1~ is carried upwards to~e-ther with ~the mould 6 by one vertical transfer geal 10 relative to the mel-ted in~ot 12.
If the base pla-te 6 of the plant (~ig. 4) is equipped wi-th -the gear 14 for ver-tical transler of the ingot 12, the melted ingo-t 12 is carried downwards b~ said vertical -tran~- -~er ~ear 14 wi-th -the non-consumable elec-trode 15 and mould 16 being s-ta-tionary.
Shown in ~ig. 5 is a cross-sec-tional view of a non-con- -sumable electrode 15 which is made as a hollow rod.
However, someti~es in -terms o~ design it is more conve- ~
nien-t to emplo~ a non-consurnable electrode made as plates 18 -- -(~ig. 6) encompassing partly or completely a consumable ele-ctrode 4, said plates 1~ being mounted on -the internal surfa-ce 13 OI' a mould 16 and insula-ted elec-trically therefrom.
Fig. 7 shows the func-tioning of a plant ~or electroslag remelting of stesl and alloys when producing a slag ingot 19.
~ mould 20 of said plan-t flares in i-ts top portion to accom-modate a slag ba-th 7 in which -the consumable electrode 4 melts. A non-consumable elec-trode 21 is an ir~ertion piece arranged on tha ~lared top portion OL -the mould 20. '~he slab ingot 19 is bei~g shaped in the bottom narrowing par-t of the -mould 20.

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Said desi~ll ol' the ~larl-t allo~s, firs-tly, remelting the elec-trodes 4 v~ith a cross-sectioll S~ `ig. ~) grea-ter than the cross-sec-tion S2 (~ o. ~) of the melted ingot 19, crea~-in~, secondly, more favourable conditions for fusinO OI the consumable elec-trodes 4 and snaping of the slab in~ot 19, a feature which renders the plant more compact and efficient.
By melting the consumable electrode 4 with the cross--section ~1 greater than the cross-sec-tion S2 of the melted slab ingot 19, with -the consumable electrode 4, non-consuma-bie electrode 21 and the mould 20 being carried upwards, ingo-ts of a large heigh-t can be produced.
Said examples are considered hereinaf'ter in detail.
If the electroslag remeltin~ process is conducted with a constan~ rate, uniformly, and -the volume of a slag bath 7 does not change, the rate of transfer of the consumable ele-ctrode 4 (Fig. 10) will 'be~

Vl ~ 2 411 (1) where Vl is -the rate of transfer of' the consumable electro-de 4;
~11 is -the length of a fused part of the consumable electrode 4;
12 is the height of` a buil-t-up par-t of -the slab in~ot ~: 19; `
t is a time interval under consideration.
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108~58 l'he buildin~-up rate (V2) of the slab in~o-t 19 or that with which the slag -ba-th 7, mould 20 and ~on-co~sumable ele-ctrode 21 mo~e will become equal accordinOly:
V2 = 12 (2) at ~rorn -t~e equations (1) and (2) it c~n be ~ound;
Vl 1 A
V2 ~` 12 ~ rom the equali-ty of volumes of remelted metal of the consumable elec-trode and -that of tile obtained slab ingot 19:
~1- a 1l = S2- ~12 (4)~
or 1 = S2 (5).
~ 12 Sl Substitutin$ ~quation (~) into ~qua-tion (3) ~2 Vl = V2 ~1 - - ) (6) Subs-tituting practically possible limi5s 0~ 2 = 0.95 - 0.05 in-to Equa-tion (6), i-t is possible -to find out the rate (Vl) of transfer of the consumable electrode 4 which amou~ts -to 0.05 - 0.95 the rate (V2) of travel of the `~
slag ba~th 7.
r~he foregoing is illustrated below by an example.
rlhe cross-section S1 of the consumable elec-trode 4 is twice as ~reat as the cross-section S2 of a slab ingot 19 - ., ,. -. . - :- . .
.- . . ~
.
- ~ - ' ' '-_ 26 --bein~ melted. L'he~ by mo~mtin~ tl-le consumable electrode 4 in the middle oI` a rnaqt 1, its ~e~lel-ting in -the slag ba'~h 7 is ini-tia-ted. In this case the building-up rate (V2) o~' the slab ingo-t 19 will be twice as great as the rate of ~'usi~g (Vl) of -the electrode 4, according -to ~`quation (6), both rates being directed upwards. 'i'he non-consumable electrode 21 and mould 20 are carried upwards at the ra-te of travel of said slag bath 7 by which virtue the ends oi' the consumable ele-ctrode 4 and non-co~sumable elec-trode 21 are immersed in said slag bath 7.
In the above exarnple as the elec-trode remel-ting process comes to an end, the electrode 4 will reach the top end of the mast 1, in other words, i-t will pass the distance equal to one half` o~ the height of -the mas-t 1. At the same time the height increment of the slab ingo-t 19 will be twice as great as said path passed by the electrode 4, i.e. the height o~ the slab ingot 19 will be equal to tha-t of` the mast 1.
I~aturally, the electrodes and ingots may di~f'er in shape.
~ he present invention rnay prove to be most advan-tageous in producing slab ingots. In this case owing tc a large ingot height a cas-ting (a slab ingot) can approach to a maximum ex-tent a rolled sheet, diminishing thereby the reouisite reduc-tion degree and cutting down the rolli~g cycle. I~oreover~ the use of low-height consurnable electrodes 4 o~' a large cross--section, as well as the ~act that -the remel-ti~g process is conducted in -the slag bath 7, heat-insulated f'rorn the cooled ' . ' . , ~ ~7 ~

Wa11S OI tii6` i~ould 2~ by an ilsertion piece shaped as a non--co~lsw-~able elec-trode 21, oiI`ars ~1 abrupt decrease in ele-ctric energy collsu~lption, i.e. e~lances tfle plan-t e~ficien~
All ~tL~e ~ore~oin~ cuts ~o~n botfl-the cost o-f rle-tallurgi-cal produc-tion and me-tal conversion expenditures.
~ `ig. 11 shows -the prvduc-tion o~ a slab in~o-t 19 on a plant wi-th a base plate 6 being ~`i-tted Wi-tfl a g-ear 14 for vertical transfer o~ said slab ingot 19. Durin~ electroslag remelting on said plant -the slab ingo-t 19 is carried down-wards by the vertical trans~er gear 14 so -that tne level o~
a slag bath 7 remains constant relati~e -to the i~movable non--consumable elec-trode 21 and mould 20, the consurna'ole electro-de 4 being carried downwards, as it melts.
Said method o~' electrosla~ rel~leltin~ in combination with the above-outlined p~ocedure (with a consurnable elec-trode being shif`ted upwards) ~akes i-t possible to melt slag ingo-ts 19 o~ a height equal to -the surn o~ dis-tances passed by the gears 10 and 14, i.e. practicall-~ the slab ingot 19 can ex-ceed in height -that OL the fnast 1 ~ or a value of possible descend of the base plate 6.
Owing to such large dimensions the slab ingo-t 19 can be `-employed as a plate even wi-thou-t rolling, mee-ting the requi-rel~ents as to i-ts quality. '~he present invention is of parti-cular advantage i~ ship-building when manu-~acturing ships' hulls. Economic expediency OI` -this applica-tion is quite ob-vious.

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' - ~ .. , . - .- ~ : -Considare~ hereil1below is -ti1e produc-tion o~ -~ube sk~lps.
~ ig. 1~ shows one of the embodiments o~' a plan-t ~'or ele-ctroslag ram~1-ting o~ metals and alloys for producingj a tu~e skelp 22. On said plant a non-consumable electrode is made hollow -to accommodaie a mandrel 24 ~'ixed therein. Placed be-t-ween a non~consumable elec-trode 23 and an external surf~ace o~' the mandrel 24 is a layer ol ~lec-tric insulation 25 preclud-in~ the passage of an electxic current through the mandrel 24.
A consumable electrode 26 is ~ade as a tube or of separate rolled bars and encompasses a-t least partly the non-consuma-ble electrode 23.
'~he non-consumable elec-trode 2~ may consti-tute a hollow cylinder 2~ (Fig. 13) or it can be made as separate plates 27 ;
(~ig. 14) arranged around the mandrel 24 and encompassing it ~ -par-tly or completely. -, The plant ~unctions in the ~ollowing manner.
Upon mou~ting a low-height mould 28 on a base pla-te 6 (~ig~12), with -the mandrel 24 being fixed on the upper part of said mould 28, said mandrel being fitted with a hollow non-consumable electrode 2~, molten slag s-tart is provided by pouring a preliminary heated slag bath 7 in a mould 28 reach-ing such a level that the end o~ the non-consumable electrode -23 happens to be submerged therein-to. ~ollowing that a consu- -m~ble electrode 26 is immersed in said slag bath 7 and by --, passing an eleotric curren-t from the a.c. supply souxce 11 through the consumable electrode 26, slag bath 7 and non-con-. ~ , ~ ~ .
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, _ ~9 _ sumable electrode 23 the electrosla~ remel-ting ~rocess is ini-tial,ed.
As the me-tal of the consumable el~c-trode 26 start melt-ing~ the ~ear 10 carries -the norl-consumable elec~trode 23 -toget~er with the mandrel 24 and -the mould 28, -the tube skelp 22 remainillæ i~movable. The movinO internal surface 1~ of t~e .
mould 28 shapes an external surface oi` the tube skelp 22, while an external sur~ace 25 o~`-the mandrel 24, on being -transferred upwards, shapes the internal sur~`ace of -the tube skelp 22.
'~he inherent design of -the mandrel 24 with the hollow non-consumable electrode 23 fixed on i-ts upper portion is favourable in that it reduces heat losses of the slag bath 7, .
provides better conditions for ~elting the consumable electro-de 26 by ensuring better current distribution in the slag bath and precludes elec-tric erosion of tha mandrel 24.
~ ig. 15 illustrates the operation o~ a plant ~or elec-tro-slag re~lelting when p~oducing the tube skelp 22 by using the ~ertical transfer gear 14. In this case ~the tube skelp 22 is .~ :
carried downwards -by the ver-tical -transfer gear 14, non-consu-mable electrode 23, mandrel 24 and mould 28 bein~ s-tationary ..
so that the level of -the slag ba-th 7 remains cons-tan-t. -~ ;- -Said plant provides better servicin~ conditions.
~ ig. 16 illustrates the operation of a plant when .ro- -~ducing the -tube skelp 22 with a non-consumable electrode 30 made as two hollow cylinders of any desired cross-section, ' .. ...

' . :: ~ - -. . . . , . . . ~

- ' . - .
, . - : ' , ~088758 o:E wllich one is fixed on the inteInal surL~ace 13 of the mould 16 and the other ore on the ~1andrel 24.
Said desi&~n o~ the non-consumable electrode creates optimum conditions ~`or current dis-tribution in the slag bath 7 around the consumable electrode 26, ensuring i-ts melting.
ItIoreover, in this case the non-consumable electrode 30 ac-ts as a heat ins~lator o~ cooled walls of -the mould 16 and man-drel 24 in the zone o~ the slag bath 7, a ~eature which dimi-hishes materially hea-t losses in -the slag ba-th 7. ~verything taken -together enhances the plant ef~iciency, i.e. decreases the specific consumption of electric power as compared with prior-ar-t installations ~or electroslag remel-ting o~ metals and alloys. .-The tube skslp is shaped similarly to the above-outli-ned, i.e. with the tube skelp 22 being stationary a~d with -~-the gear 10 moving upwards the mould 16 together wi-th the ma~drel 24 and non-cons~mable elec-trode 30.
In another embodiment the mould 16 (~'ig. 17), mandrel 24 and non-consu~able elec-trode 30 are immovable and the tube skelp 22 mounted on the base plate 6 is carried downwards by the gear 14.
~ his creates bet-ter conditions for plant servicing, in-so~ar as the mould 16, mandrel 24 and the non-consumable ele-ctrode 30 are stationary a~d can be easily obssrved during the entire process.

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108~7S~

l~'ig. 1~ illus~ates tiLe ol)eration of a plant when pro-ducing the ~ube skelps ~2 ~ith a wall thick~ess smaller -than tile Cl'OSS-SeC tiOn OI cons~-,lable electrodes 31.
~ `ixed on tlle mould 20 with the ~lared -~op portion is a hollo~v non-consumable elec-trode ~2 irlsulated electrically by the layer 17 of elec-tric insula-tion from -the walls of -the mould 20. Arrar~ed on -the top paxt of the mandrel 24, narrow-ingr towards its -top portion, is -the hollo~v--I~on-consumable elec-trode 23 insula-ted -through -the layer 25 o~ elec-tric in-sulation fro~ the walls o~ the mandrel 24. ~`he consumable elec-trodes 31 made up of individual bars ~Jith a ~otal cross--sectional area of Sl (~i~. 19) greater than -the sec-tional area S2 (~ig. 20) of the tube skelp 22 bein~ melted are re-melted in -the flared portion bstween the non-consurnable ele-ctrodes 32 and 23.
~ he tube skelp 22 (~ig. 1~) is shaped sirnilarly -to the above-described procedure of producing a slab ingot, i.e. by carrying the consumable electrode 31, mould 20 and non-consu- -~mable electrodes 23 and 32 upwards.
Both non-consumable electrodes 23 and 32 and the mould 20 are trans~erred at a ra-te V2 that is equal to that o~ -the slag bath 7 which corresponds to the building-up rate of the - -tube skelp 22. ~he consumable electrode 31 is carried upwards a-t a ~ate of `0.05 - 0.95 -the rate o~ the slag ba-th 7 depen-ding on the ratio o~ cross-sectional areas o~ the consumable electrode 31 (Sl) and tha -tube skelp 22 (S2) being ob-tained.

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'~hus, it is possi~le ~ produce high ~hin-walled tube skelp 22. ~he inven-tio1l is par-ticula~ly efLicient economi-cally when producinO -tu~bes in hard-to-work alld non-delor~aole:~
steels. At presen-t such tubes are usually pro(luced by ~orgring and drilli~
l~ig. 21 ~hows t-he operation of a plan-t provided with -the gear 14 ~or vertical -trans~er of -t~le base pl~-te 6. Wi-th the help of said gear 14 the tube s~elp 22 is lowered, as i~
is built-up, so tha-t the level o~ the slag bath 7 remains cons-tan-t with respect -to -the stationary non-consumable ele-c-trode 31 beingr carried down~-vards, as it melts.
As the tube skelp 22 is carried down~ards, i-ts atten-dance becomes more convenien-t, since the mould 20, non-consu-mable electrodes 23 and 32 and slag bath 7 are immovable during the en-tire process simplifying supervision and car-rying out of the requisite produc-tion operations.
Moreover, the down~ard motion o~ -the -tube skelp 22 and consumable electrode 31, with the mould 20 and non-consu~ab- -le electrodes 2~ and 32 beingr stationary, and in combination with an upward mo-tion of the consumable electrode 31, mould .20 and non-consumable electrodes 23 and 32 e~ables the pro-duc-tion o~ still higher tube skelps 22.
The latter is o~ prime importance when producin~ tubes, since it is quite eviden-t -tha~ the larger -the length o~ a tube being -produced, -the smaller is -the a~uunt o~ as~mbly welds, this being proLitable ~or a tube consu~er, renders , - '- ~ . : .

~088758 tlle l~ ~`aturer l)roclucts Lilore competitive by cutting down the produc-tion cost, as com~ared ~ th the -tube-makin~i ~roced~es in curren-t use~ and ensures ~ioh quali-ty of material.
Considered hereinaf-ter is the fabrica-tion of hollo1;~
castings with a bo-t-tom in --~heir lowe~ portion.
~ ig. 22 illustrates -the prod~c-tiorl ol' a hollo-~i casting 33 ~7i-th a bottom 34 in its lower por-tion.
Upon es-tablishing -ti-le slaO ba-th 7 an elec-tric current is passed by rneaIls OI a Swi-tCi1 35 -ti~ouOh -the consumable elec-trode 26, sla~ bath 7 and base pla-te 6, with -bhe non-con-sumable elec-trode 2~, mandrel 2L~ arld a mould 2~ beinO statio-nary. Under the effec-t of the elec-tric c~rren-b the end of -the consumable electrode 26 m~l-ts~ me-tal drople-ts collec-ting in -the bo-ttorll part of -the ~nould 28 and solidifyinO on the base plate 6 -to form the bottom ~4~ Gradually bo-th the slag bath '~
7 and a metal pool 36 climb upwards alon~ -the ~enera-trix of , the mandrel 24. UPO1L coming in con-tac-t ~ith -the surface of the cooled mandrel 24 liquid me-tal of the metal pool ~6 soli- --difies formillg walls of tl-le interior 37, while the slag bath 7 reaches the end of the non-consumable electrode 23. As soon as the end o~ the non-consumable electrode 23 is immersed in , the slag bath 7 the switch 35 disconnects -the pole of the current supply source 11 from the base plate 6 connec-ting it --to the non-consu~able electrode 23. Af'ter t~a-t -the elec-tric current is passed through the consumable electrode 26, slag bath 7 and the non-consumable electrode 2~. ~t -the same -time .. , .. -:
. . - . .
'' ' :, ,: -_ 3L~ _ -til~ ~an~rel c4 Wit~l the non-con~lablQ electrode 23 and mould 28 are carried upwards and u~ to -the end of -the process -the rerilaining pOItiOll o~ the hollow cas-ting is Lrloulded similarly to -the above-outlined procedure user~ when producing the tube skelp.
Shown in ~i~. 2~ is an errlbodimen-t illus-trating the pro-duction of the same hollow cas-ting by using -the vertical -transfer gear 14.
Wi-th the plant opera-tin~ in the above maI~er upon shap ing the bot-tom 34, -the hollow casting ~ is carried downwards, the mandrel 24 non-consurQable electrode 23 and the mould 28 being sta-tionar~. Said method is particular~ly efIicient eco-nomically for producing variou6 high-pressure vessels: pump bodies, hydraulic (oil) plants and compressor bodies.
~ 'igs 24 and 25 show rela-tive position o~ -the plant pa~ts at -the begLnning and at the end of -the electroslag remel-ting process when producing a hollow shaped casting 38 with a bot-tom 39 in its lower portion.
Projecting parts of the shaped casting 38, made as bos-ses (of the branch pipe, flange or some other type), do nob enable the transfer of an external mould 40 during the melt-ing process; therefore upon producing -the bottom ~9 of a gi-ven thickness, tha-t is effected similarly -to the preceding case, and upon co~necting -the pole of tne curren-t supply source 11 to the non-consumable electrode 23, -the mandrel 24 ~ith said non-consumable electrode 2~ is carried upwards at .

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a r.lGe e~ual ~o -tha~ OI ~,lle sl.~g bath 7~ t'le mould 40 bein,-~statioll.ry. ~t the end o~ the .)r~cess, upon ascer-taining the exac-t instan-t the formi1lg shrink nole -legulation mus-t be started, and UpOll disconnecGin~ -the curren-t supply source 11 the ra-te of wi-thdrawal o~ -the ~andrel 24 is increased so as to provide i-ts free remo~al ~ithou-G being jar~ed by the f'or-ces arisin~ on -the side OL' the casting ~ durin~ its shrin-kage.
~ 'hus, said method can be successfully employed f'or pro-ducin~ various shaped cas-tings, such as -the bodies o~' power fittings and gates, reactor vessels ~or atomic power s-tatio-~s e-tc. ' "' Considered hereinbelow is the operation of a plant, ac-cording to -the in~ention, with -the consumable electrode 4 bein~ replaced during melting (~ig. 26)o In contra~t to the above plant a current swi-tch 41 is connected from one side -to one of -the poles of -the current supply source 11 and from the other -to -the consurirlable electr~
de 4 o~ the base plate 6.
Elec-trosla~ remelting o~ the consumable electrode 4 is effected si~ilarl~ to -the abo~e-outlined procedure, until said electrode melts. ~ext the current supply source 11 is disconnec-ted from the co~sumable electrode 4 and connected to the base plate 6. In -this case the elec-tric current pas-' sing through -the non-consumable electrode 15, slag bath 7, .:
ingo-t 12 and -the base pla-te 6 maintains tile slag ba~th 7 and the metal pool 36 in hot fluid s-ta-te.
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.

At this tilile ~lle co~unla~le electrode 4 i~ replaced, ~ith -the end of~ a new consu~able electrode being iI~roduced in-to ~he slag ba-th 7. After that the new consumable electrode 4 is co~lec-ted -to -the cur~ent suppl~ source 11 by -the swi-tch 41 and electroslag remelting of` said new consumable elec-trode 4 continues.
Evidently, said replacel-nen~ o~ consu~able electrodes can be eff'ected as many -ti~es as it i~ re~uired, enabling -t e production of heavy ingo-ts 12 b-y relnel-ting small elec-trodes.
Hence, when replacing the electrode 4, the meral pool 36 is sus-tained in hot fluid state which ensures a homogenous ingot structure and a high-quali-ty surface. ~'he plant is con-venient in ~ervice, does not require additional devices and gears, is noted for its low height and a comparatively low power input when producing ingo-ts of' various weight.
~ ig. 27 shows the operation of said plant f'itted wi-th the gear 14 f'or vertical trans~er o~` the ingot 12 a-t the in-stant of' ~itting the next consumable electrode 4.
It is obvious that in all the above-outlined cases the proposed plant can opera-te by replacin~ the consumable ele-ctrodes in the cowrse of' melting and these cases will not be --considered in detail.
~ o summarize considered hereinbelow will be the functio-nin~ of an electroslag remeltin~ plant ~ en producing shaped castings wi-th concurrent fusing of a member which can be made . . ~. . . . . ~ . ~ . --- : . . -- - : .

- . . .
-108~758 oi rolled products, ~orOinOs or prefabrica-ted by the electro-slag remeltiIlg -technique.
Relative position OL` -the ~lant par-ts a-t the beginninO of electroslag remelting with concurrent joinin~ of a fused mem-.-ber 42 is shown in l~i~. 28.
A base plate 43 has an opening into v~hich -the member 42 -~- --to be ~used is int-roduced before -the ~rocess is initia-ted.
~he plant is fi-tted with a current switch 44 connected from one side to one of the poles oi` the curxent suppl~J source 11 and ~rom the o-ther -to the ~used rnember 42 or to the consuma-ble electrode 4.
'~he plant operates in the follo~in~ rnanner.
U-pon es-tablishing -the slag ba-th 7 (molten slag starting) the switch 44 connec-ts one pole of the current supply source 11 -to the fused member 42. Hence, a~ elec-tric current is pas-sed through ~he non-consumable electrode 15, the slag bath 7 and fused member 42 until i-ts -top end face 45 fuses, with the ~ :
consumable e:Lec-trode 4 being withdrawn from the slag bath 7. -.
'~hen the end of the consumable electrode 4 is submerged into - --the slag bath 7 and the pole o~ -th~ current supply source 11 is disconnected by -the swi-tch 44 from -the fused member 42 and connected to the consumable electrode 4. '~hus, the electro- -sla~ remelting of the consumable electrode 4 (~'ig, 29) is carried out by passing the electric curren-t thro~gh said con-sumable electrode 4, the slag bath 7 and non-consumable ele-ctrode 15.
, . ' ~, : , ' ' . '' ' ' ' - . , :, ,; ,.,,..... ... ~:

10~758 Preli!~in~ry fusing ol~ tilt'i top end face 45 of tLle fused member 4~ ens~ues a guarallteed high-quali-ty joint 46 betvJeen the ~used me~ber 42 and a casting body 470 Said ~ethod is particularly useful ,or Droducin~ shaped combination castings with various cross-section, such as, cold rolls, covers for power fi-ttin~ bodies, e-tc., and for IUSi~g finished mernbers of an ar-ticle to one of its par-ts~
in the course o~ electrosla~ remel-ting, ob7~iating thereby welding, cut-ting down ultimately the produc-tion cost and en-s~ring hi~h quali-ty of the ~inished produc-t.
~ ig. 30 shows allother possible e~bodimen-t of a plant when producing a cold roll 48 by fusing in -the course of ele-ctroslag remelting its neck 49 which may be made by rolling, by remelti~g a plurality of -the electrodes 4 one after ano-ther and carrying -the base plate 43 downwards by the vertical ;
transfer gear 14.
It stands to reason that -the present inven-tion is not limited to -the disclosed par-ticular embodimen-ts which must be considered by way of illustrations only. ~articularly such are all the devices w~ich cons-ti-tute technical equivalents of said devices disclosed hereinbefore, as well as their com-~binations, in case they are made without departing from the spirit and scope of the in~ention as set forth in the appen-ded claims.

Claims (37)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:-

1, A plant for electroslag remelting of metals and alloys, comprising: a cooled base plate; a cooled mould set up on said cooled base plate; a slag bath contained in said cooled mould, a current supply source; a consumable electrode submerged with one end into said slag bath, its other end being connected to one of the poles of said current supply source; said consumable electrode being carried by a vertical transfer gear; at least one non-consumable electrode connected to the other pole of the current supply source in series with said consumable electrode; said non-consumable electrode and cooled base plate being movable relative to each other in a vertical direction.

2. A plant for electroslag remelting of metals and alloys, as claimed in claim 1, in which said non-consumable electrode is fitted with a vertical transfer gear ensuring its vertical motion with respect to said base plate.

3. A plant for electroslag remelting of metals and alloys as claimed in claim 1, in which said base plate is furnished with a gear for vertical transfer of an ingot being melted, said gear ensuring vertical motion of said base plate relative to the non-consumable electrode.

4, A plant for electroslag remelting of metals and alloys, comprising a cooled base plate; a cooled mould mounted on said cooled base plate; a slag bath accommodated in said cooled mould, a current supply source; a consumable electrode submerged with one end into said slag bath, its other end being connected to one of the poles of said current supply source; said consumable electrode being carried by a vertical transfer gear; at least one non-consumable electrode connected to the other pole of the current supply source in series with said consumable electrode; said non-consumable electrode is made hollow and fixed on the internal wall of said cooled mould and insulated electrically therefrom and said consumable electrode is disposed therein.

5. A plant for electroslag remelting of metals and alloys, as claimed in claim 4, in which said mould and the non-consumable electrode are carried upwards by said vertical transfer gear, the ingot being stationary.

6. A plant for electroslag remelting of metals and alloys, as claimed in claim 4, in which said base plate is fitted with the gear for vertical transfer of the ingot being melted.

7. A plant for electroslag remelting of metals and alloys, as claimed in claim 4, in which said non-consumable electrode is made as current-carrying plates encompassing said consumable electrode, set up on the internal surface of said mould and insulated electrically therefrom.

8. A plant for electroslag remelting of metals and alloys, as claimed in claim 7, in which said current-carrying plates are arranged along the entire perimeter of the internal surface of said mould.

9. A plant for electroslag remelting of metals and alloys, as claimed in claim 1, in which said non-consumable electrode is made hollow and accommodates a mandrel that is fixed therein and insulated electrically therefrom, said consumable electrode encompassing at least partly said non-consumable electrode and being submerged with its bottom end into said slag bath.

10. A plant for electroslag remelting of metals and alloys, as claimed in claim 9, in which said non-consumable electrode, mandrel and mould are carried upwards by one verti-cal transfer gear ensuring the production of a tube skelp.

11. A plant for electroslag remelting of metals and alloys as claimed in claim 9, in which said base plate is equipped with a gear for vertical transfer of the tube skelp being melted.

12. A plant for electroslag remelting of metals and alloys, as claimed in claim 9, in which said non-consumable electrode is made as current-carrying plates.

13. A plant for electroslag remelting of metals and alloys, as claimed in claim 9, in which said plant is fitted with a current switch connected from one side to one of the poles of the current supply source and from the other to said plate or non-consumable electrode, ensuring the production of a hollow casting having a bottom.

14. A plant for electroslag remelting of metals and alloys, as claimed in claim 1, in which the non-consumable electrode is shaped as two hollow rods of any desired cross-section, concentric with each other, one of said rods accom-modating the mandrel insulated electrically therefrom whilst the other rod is disposed on the internal surface of the mould and is also insulated electrically therefrom, with the con-sumable electrode being made hollow, mounted between said hollow rods, concentric therewith and submerged with its bottom end into the slag bath.

15. A plant for electroslag remelting of metals and alloys, as claimed in claim 14, in which said non-consumable electrode, the mandrel and mould are carried upwards by one vertical transfer gear relative to the tube skelp being melted.

16. A plant for electroslag remelting of metals and alloys, as claimed in claim 14, in which the base plate is fitted with the gear for vertical transfer of the tube skelp being melted.

17. A plant for electroslag remelting of metals and alloys, as claimed in claim 1, in which said base plate has an opening into which is introduced a fused member, the plant being fitted with a current switch connected from one side to one of the poles of the current supply source and from the other to the fused member.

18. A plant for electroslag remelting of metals and alloys, as claimed in claim 1, in which said base plate has the opening in which the fused member is fed, the plant being furnished with the current switch connected from one side to one of the poles of the current supply source and from the other to the consumable electrode.

19. A plant for electroslag remelting of metals and alloys, as claimed in claim 1, which comprises the current switch connected from one side to one of the poles of the current supply source and from the other to the base plate.

20. A plant for electroslag remelting of metals and alloys, as claimed in claim 1, which comprises the current switch connected from one side to one of the poles of the current supply source and from the other to the consumable electrode.

21. A plant for electroslag remelting of metals and alloys, as claimed in claim 1, in which the non-consumable electrode is made of graphite.

22. A method of electroslag remelting of metals and alloys on a plant, comprising a consumable and non-consumable electrode, said method consisting in that during the entire electroslag remelting process an electric current is passed through the consumable electrode, the slag bath and non-consumable electrode, and in which, during the entire electro-slag remelting process, the non-consumable electrode is carried upwards by a vertical transfer gear with a rate that is equal to that of the slag bath, maintaining thereby the end of the non-consumable electrode submerged into said slag bath, with the consumable electrode being carried downwards as it melts to produce an ingot of remelted metal.

23. A method of electroslag remelting of metals and alloys, as claimed in claim 22, in which the ingot set up on said base plate is carried downwards, as it is built-up, by the vertical transfer gear so that the level of the slag bath is constant with respect to the stationary non-consumable electrode and mould.

24. A method of electroslag remelting of metals and alloys, as claimed in claim 22, in which the non-consumable electrode is carried upwards together with the mould by the vertical transfer gear with respect to the ingot being melted.

25. A method of electroslag remelting of metals and alloys, as claimed in claim 22, in which the melted ingot is carried downwards by the vertical transfer gear with the stationary non-cnnsumable electrode disposed on the internal wall of the mould.

26, A method of electroslag remelting of metals and alloys on a plant, comprising a consumable and non-consumable electrode, said non-consumable electrode accommodating a mandrel that is fixed therein and insulated electrically therefrom, said method consisting in that during the entire electroslag remelting process an electric current is passed through the consumable electrode, slag bath and non-consumable electrode, and in which, for producing a tube skelp, the non-consumable electrode is carried upwards together with the mandrel by a vertical transfer gear, the tube skelp being immovable.

27. A method of electroslag remelting of metals and alloys, as claimed in claim 26, in which the tube skelp is carried downwards by a vertical transfer gear with the non-consumable electrode, mandrel and mould being stationary so that the level of the slag bath is constant.

28. A method of electroslag remelting of metals and alloys, as claimed in claim 22, in which the consumable and non-consumable electrodes and the mould are carried upwards, the consumable electrode being transferred at a rate of 0.05-0.95 the rate of the slag bath, whilst the non-consumable electrode and the mould are transferred at the rate of said slag bath, maintaining the ends of the consumable electrode submerged into the slag bath and ensuring the production of an ingot of remelted metal, said ingot being superior in length to the melted electrode.

29. A method of electroslag remelting of metals and alloys, as claimed in claim 22, in which the ingot is carried downwards by the vertical transfer gear so that the level of the slag bath remains constant with respect to the stationary non-consumable electrode that is made hollow, and to the mould, with the consumable electrode being carried downwards as it melts, ensuring the remelting of said consumable electrode having a cross-section greater than that of the melted ingot.

30. A method of electroslag remelting of metals and alloys in a plant, comprising a consumable electrode, a gear for vertical transfer of a base plate and another gear for vertical transfer of a mould with a non-consumable electrode arranged on the outer surface thereof, said method consisting in that from the beginning of the remelting process the ingot is carried downwards by the vertical transfer gear to an ex-tent of a possible transfer of said gear so that the level of the slag bath remains constant relative to the stationary non-consumable electrode and mould, the consumable electrode having a cross-sectional area (S1) greater than that (S2) of the ingot being melted being carried downwards, as said consum-able electrode melts, whereupon by discontinuing the motion of the ingot by the vertical transfer gear the consumable elec-trode, non-consumable electrode and mould are transferred downwards up to the end of the process, the consumable electrode being carried at a rate of 0.05 - 0.95 the rate of the slag bath, while the non-consumable electrode and the mould are carried with the rate of the slag bath, maintaining thereby the ends of the consumable and non-consumable electrodes immersed in the slag bath and ensuring the production of the ingot of a height greater than a plant mast.

31. A method of electroslag remelting of metals and alloys in a plant provided with a consumable electrode, a non-consumable electrode in the form of two hollow cylinders of any cross-section, one of which is positioned on the inner surface of said mould and the other on the outer surface of a mandrel, and a gear for vertical transfer of the non-consumable electrode, the mandrel and said mould, said method consisting in that the consumable and non-consumable electrodes, the mould and mandrel are carried upwards, the consumable electrode being transferred with a rate of 0.05 - 0.95 the rate of the slag bath, whilst the non-consumable electrode, mould and mandrel are moved at the rate of the slag bath, maintaining therefore the ends of both the consumable and non-consumable electrodes immersed in the slag bath and ensuring the production of the tube skelp with a wall thickness smaller than the cross-section of the electrode being remelted.

32. A method of electroslag remelting of metals and alloys in a plant provided with a consumable electrode, a non-consumable electrode in the form of two hollow cylinders of any desired cross-section, one of which is positioned on the inner surface of said mould and the other on the outer surface of said mandrel, and a gear for vertical transfer of the base plate, said method consisting in that the tube skelp is carried downwards by the vertical transfer gear so that the level of the slag bath remains constant relative to the stationary non-consumable electrode, mould and mandrel, the consumable elec-trode with a cross-sectional area (S1) greater than that (S2) of the melted tube skelp being carried downwards, as said electrode melts, maintaining thereby the ends of both the consumable and non-consumable electrodes immersed in the slag bath and ensuring the production of the tube skelp with the wall thickness smaller than the cross-section of the melted electrode.

33. A method of electroslag remelting of metals and alloys in a plant, provided with a consumable electrode, a non-consumable electrode in the form of two hollow cylinders of any desired cross-section, one of which is positioned on the inner surface of said mould and the other on the outer surface of said mandrel, and a gear for vertical transfer of the non-consumable electrode, said mandrel and mould and another gear for vertical transfer of said base plate, said method consisting in that from the beginning of the process the tube skelp is carried downwards by the vertical transfer gear to an extent of a possible transfer of said gear so that the level of the slag bath remains constant relative to the stationary non-consumable electrode, mould and mandrel, the consumable electrode with a cross-sectional area (S1) greater than that (S2) of the melted tube skelp being transferred down-wards, as said electrode melts, whereupon by discontinuing the motion of the tube skelp with the aid of said gear the con-sumable and non-consumable electrodes, the mould and base plate are carried upwards up to the end of the process, the consumable electrode being transferred at a rate of 0.05 - 0.95 the rate of the slag bath, whilst the non-consumable electrode, mould and mandrel are carried with the rate of the slag bath, maintaining the ends of both the consumable and non-consumable electrodes immersed in the slag bath and ensuring the product-ion of the tube skelp having a height greater than the plant mast.

34. A method of electroslag remelting of metals and alloys in a plant, comprising a consumable and a non-consumable electrode, said non-consumable electrode accommodating a mandrel that is fixed therein and insulated electrically therefrom, and a current switch is connected to said non-consumable electrode and to a base plate, said method consisting in that at first the consumable electrode is remelted by passing an electric current through the consumable electrode, slag bath and base plate, with the non-consumable electrode, mandrel and mould being immovable until a bottom of a given thickness is obtained and until the end of the non-consumable electrode is submerged into the slag bath, whereupon up to the end of the process the current is passed through the consumable electrode, slag bath and non-consumable electrode, the mandrel with the non-consum-able electrode being transferred upwards at a rate equal to that of the slag bath, maintaining the end of the non-consumable electrode immersed in the slag bath and shaping the interior of the casting, and in which, upon shaping the bottom of a given thickness, the mandrel and non-consumable electrode are transferred together with the mould by a vertical transfer gear.

35. A method of electroslag remelting of metals and alloys, as claimed in claim 30, in which upon shaping the bottom of a given thickness the hollow casting is carried downwards by the vertical transfer gear, the mandrel, non-consumable electrode and mould being stationary.

36. A method of electroslag remelting of metals and alloys on a plant, comprising a consumable and a non-consumable electrode, said non-consumable electrode accommodating a mandrel, fixed therein and insulated electrically therefrom, said non-consumable electrode being fitted with a vertical transfer gear for the vertical transfer thereof, and a base plate having an opening in which a fused member is mounted, said plant being fitted a current switch, said method con-sisting in that upon establishing the slag bath the electric current is passed through the non-consumable electrode, slag bath and said fused member until the top end face of the fused member starts melting with the consumable electrode being with-drawn from the slag bath, whereupon the end of the consumable electrode is immersed in the slag bath, the electric current being passed through the consumable electrode, slag bath and non-consumable electrode until the electroslag remelting process is completed, ensuring a guaranteed joint between the fused member and the casting body.

37. A method of electroslag remelting of metals and alloys in a plant, comprising a consumable and a non-consumable electrode, said non-consumable electrode being fitted with a vertical transfer gear for the vertical transfer thereof, one end of the consumable electrode being immersed in a slag bath, electric current being passed through the consumable electrode, slag bath and non-consumable electrode until the electroslag remelting process is completed, said method further consisting of in that upon melting one consumable electrode the current supply source is disconnected from said consumable electrode and connected to the base plate for maintaining slag bath in hot fluid state, then the melted consumable electrode is replaced and the end of a new con-sumable electrode is immersed in the slag bath, whereupon said consumable electrode is again connected to the current supply source and the electroslag remelting of the new consumable electrode continues.