Apparatus for electroslag remelting of metals with molten slag introduction

Claim 2

A plant for electroslag remelting of metal from consumable electrodes comprising: crucible means including a bottom plate and a separable crucible placed on said bottom plate; means for disposing portions of consumable electrodes in said crucible means with lower ends thereof located adjacent the bottom of said crucible means; and means located in the lower part of said crucible means enabling introduction of molten slag from outside of said crucible means directly into the bottom portion of said crucible means through a channel means having at least a portion thereof formed by said separable crucible.

Claim 3

A plant for electroslag remelting of metal from at least one consumable electrode comprising: a crucible means including a bottom plate and a crucible device placed on said bottom plate; a holder for said consumable electrode enabling the insertion of portions of said electrode into said crucible device; a pouring device for supplying molten slag into the lower part of said crucible means; said pouring device communicating therewith through a channel formed due to linking of said bottom plate with said crucible device.

Claim 4

A plant for electroslag remelting of metal from at least one consumable electrode comprising: a crucible means including a bottom plate and a crucible device placed on said bottom plate; a holder for said consumable electrode enabling the insertion of portions of said electrode into said crucible device; a pouring device for supplying molten slag into the lower part of said crucible means; said pouring device communicating therewith through a channel formed due to linking of said bottom plate with said crucible device.

Claim 5

A plant as defined in claim 2, wherein said channel is formed by an external boring provided in said bottom plate, covered from above by end surfaces of said crucible device and said pouring device.

Claim 6

A plant as defined in claim 3 wherein said external boring is of trapezoidal cross-section.

Claim 7

A plant as defined in claim 2, wherein said channel is formed on the lower end of said crucible device by a radial boring covered from below by said bottom plate.

Claim 8

A plant as defined in claim 2, wherein said channel is formed by borings provided in the lower end of said crucible device and outside said bottom plate, said borings facing each other.

Claim 9

A plant as defined in claim 2, wherein said syphon pouring device is made detachable along the longitudinal plane of its channel.

Claim 10

In an electroslag remelting furnace the improvement comprising: crucible means which comprises a bottom plate and a separable crucible placed on said bottom plate and a conduit means adjacent the lower portion of said crucible means for the introduction of molten slag from outside said crucible means into the bottom portion of said crucible means, said conduit means having at least a portion thereof formed by said separable crucible.

Claim 11

In an electroslag remelting furnace the improvement comprising: crucible means which comprises a bottom plate and a separable crucible placed on said bottom plate and a conduit means adjacent the lower portion of said crucible means for the introduction of molten slag from outside said crucible means into the bottom portion of said crucible means, said conduit means having at least a portion thereof formed by said separable crucible.

Claim 12

A furnace as defined in claim 8, wherein said aperture is, at least in part, formed through said Crucible means at a point above said bottom plate.

Claim 13

A furnace as defined in claim 8, wherein a consumable electrode means extends into said crucible and wherein said aperture is formed through said crucible means at a point below the lowermost end of said electrode means.

Claim 14

In a furnace for electroslag remelting of metal from at least one consumable electrode extending into a crucible means and having means for causing relative motion between said electrode and said crucible means and wherein said crucible means comprises a bottom plate and a separable crucible placed thereon, the improvement comprising: conduit means extending into the lower portion of said crucible means and having at least a portion thereof formed by said base plate and said separable crucible, and said conduit means extending outwardly and upwardly thereof whereby sag poured into the outer and upper portions of said conduit means is introduced into the lower portion of said crucible means.

Claim 15

In a furnace for electroslag remelting of metal from at least one consumable electrode extending into a crucible means and having means for causing relative motion between said electrode and said crucible means and wherein said crucible means comprises a bottom plate and a separable crucible placed thereon, the improvement comprising: conduit means extending into the lower portion of said crucible means and having at least a portion thereof formed by said base plate and said separable crucible, and said conduit means extending outwardly and upwardly thereof whereby sag poured into the outer and upper portions of said conduit means is introduced into the lower portion of said crucible means.

Claim 16

A furnace as defined in claim 11, wherein said conduit means enters said crucible means at such a point to permit introduction of slag into said crucible means at a point below the lowermost end of said electrode.

Claim 17

A furnace as defined in claim 11, wherein said conduit means enters said crucible means at a point above its said bottom plate.

Claim 18

A furnace as defined in claim 11, wherein said crucible means comprises a sidewall having an outwardly extending flange at the bottom thereof mounted on said bottom plate and wherein at least a portion of said conduit means comprises a recess in said bottom plate extending beneath said flange.

Claim 19

A furnace as defined in claim 14, including upwardly extending funnel means connected to said recess, said funnel means being constructed to receive molten slag poured thereinto outside of said crucible means and to deliver said slag under gravity flow through said recess into said crucible.

Claim 20

A furnace as defined in claim 15, wherein said funnel means is removably attached to said bottom plate.

Claim 21

A furnace as defined in claim 15, wherein said funnel means extends upwards sufficiently to hold molten slag at a higher level than the lowermost end of said electrode when it is pre-positioned to a furnace start-up location.

Claim 22

A furnace as defined in claim 11, wherein a plurality of electrodes extend into said crucible.

Claim 23

A furnace as defined in claim 11, wherein the cross sectional area of said conduit means ranges from 6 to 120 square centimeters.

Claim 24

A furnace as defined in claim 19, wherein said conduit means extends into said crucible means a distance ranging from once to twice the depth dimension of said conduit means.

Claim 25

A furnace as defined in claim 11, wherein the electrode is so placed that the gap between the electrode and crucible wall ranges from 5 to 100 millimeters.

Claim 26

A furnace as defined in claim 20, wherein said conduit means is at least partially lined with a refractory material.

Claim 27

A furnace as defined in claim 14, wherein said recess has a cross sectional area of 6 to 120 square centimeters at a point beneath said flange and extends into the interior of said crucible means beyond said sidewall a distance of once to twice its depth beneath said flange.

Claim 28

A furnace as defined in claim 23, including upwardly extending funnel means connected to said recess, said funnel means being constructed to receive molten slag poured thereinto outside said crucible means and to deliver said slag under gravity flow through said recess into the interior of said crucible means.

Claim 29

A furnace as defined in claim 24, wherein said funnel means is removably attached to said bottom plate.

Claim 30

A furnace as defined in claim 25, wherein funnel means extends upwardly sufficiently to hold molten slag at a level higher than the lowermost end of said electrode.

Claim 31

A furnace as defined in claim 26, wherein said funnel means extends upwardly sufficiently to hold molten slag at a levEl ranging from one-fourth the smallest transverse sectional dimension of said ingot to be formed to twice the smallest transverse sectional dimension of the ingot to be formed.

Claim 32

A furnace as defined in claim 14, and including a funnel means having a funnel with a conduit extending downward therefrom and having at the lower end of said conduit a flange attached to said bottom plate and communicating with said recess.

Claim 33

A furnace as defined in claim 28, wherein said conduit extends upwardly at an acute angle to the vertical.

Claim 34

A furnace as defined in claim 28, wherein said recess extends from the interior to the exterior of said crucible means, passing beneath said sidewall, said sidewall flange and said conduit flange to communicate with said conduit.

Claim 35

An electroslag refining furnace system comprising: a water cooled crucible means including a bottom plate and a crucible device, said crucible means having consumable electrode means extending into the top thereof and current supply means connected into a circuit with said electrode means to initiate flow of current when electrically conducting slag contacts said electrode means; and fluid communicating means from exterior to interior of said crucible means comprising conduit means in the lower portion of said crucible means, said conduit means having at least a portion thereof formed by said base plate and said crucible device, whereby molten slag poured into said upwardly extending conduit means flows by gravity through said conduit means into the bottom of said crucible means to create in said crucible means a rising pool of molten slag that reaches a level to contact said electrode means whereby said current flow commences.

Claim 36

An electroslag refining furnace system comprising: a water cooled crucible means including a bottom plate and a crucible device, said crucible means having consumable electrode means extending into the top thereof and current supply means connected into a circuit with said electrode means to initiate flow of current when electrically conducting slag contacts said electrode means; and fluid communicating means from exterior to interior of said crucible means comprising conduit means in the lower portion of said crucible means, said conduit means having at least a portion thereof formed by said base plate and said crucible device, whereby molten slag poured into said upwardly extending conduit means flows by gravity through said conduit means into the bottom of said crucible means to create in said crucible means a rising pool of molten slag that reaches a level to contact said electrode means whereby said current flow commences.

Claim 37

In a furnace for electroslag remelting of metal having a crucible with wall means defining a furnace start-up remelting zone by the lower portion thereof and at least one consumable electrode adapted to depend into said crucible with its lowermost end in said remelting zone and having means for applying electrical power to said electrode to melt the same, the improvement comprising: conduit means through said lower portion of said crucible communicating with said remelting zone and including a slag conducting aperture opening into said remelting zone; recess means formed in said wall means of said crucible in the remelting zone thereof; and weld lug means in and pressed against at least a portion of said recess means to provide electrical contact between said weld lug means and said crucible.

Claim 38

In a furnace for electroslag remelting of metal having a crucible with wall means defining a furnace start-up remelting zone by the lower portion thereof and at least one consumable electrode adapted to depend into said crucible with its lowermost end in said remelting zone and having means for applying electrical power to said electrode to melt the same, the improvement comprising: conduit means through said lower portion of said crucible communicating with said remelting zone and including a slag conducting aperture opening into said remelting zone; recess means formed in said wall means of said crucible in the remelting zone thereof; and weld lug means in and pressed against at least a portion of said recess means to provide electrical contact between said weld lug means and said crucible.

Claim 39

A furnace as defiend in claim 32, wherein said slag conducting aperture is located in said crucible wall means at a point above the lowermost boundary of said remelting zone.

Claim 40

A furnace as defined in claim 32, wherein said slag conducting aperture is located in said crucible wall means at a point above the lowermost end of said consumable electrode.

Claim 41

A furnace as defined in claim 32, wherein said crucible includes a bottom plate at the lowermost end thereof and said slag conducting aperture is located in said bottom plate.

Claim 42

A furnace as defined in claim 35, wherein a second aperture is located in said crucible wall means.

Claim 43

A furnace as defined in claim 36, wherein said weld lug means is of the same composition as the ingot to be formed in said crucible.

Claim 44

A furnace as defined in claim 32, wherein a plurality of consumable electrodes are adapted to depend into said crucible.

Claim 45

A furnace as defined in claim 32, including upwardly extending funnel means connected to said slag conducting aperture, said funnel means being constructed to receive molten slag poured thereinto outside said crucible wall means and to deliver said slag by gravity flow through said aperture into said remelting zone.

Claim 46

A furnace as defined in claim 32, wherein a plurality of consumable electrodes are adapted to depend into said crucible and wherein said crucible has at its lowermost end a bottom plate, and said means for applying electrical power comprises an AC power circuit including said electrodes and a current balancing line connected to said bottom plate whereby current flowing through said electrodes can be increased or decreased by said circuit in order to maintain equal rates of melting of said electrodes.

Claim 47

A furnace as defined in claim 40, wherein said AC power circuit includes the secondary winding of a transformer and wherein there are two consumable electrodes, each connected to an opposite side of said secondary winding and wherein said balancing line is connected as a center tap from said secondary winding.

Claim 48

A furnace as defined in claim 40, wherein said weld lug means is in direct electrical contact with both of said bottom plate and said balancing line.

Claim 49

In a furnace for electroslag remelting of metal having a crucible with wall means defining a remelting zone by the lower portion thereof and plural consumable electrodes adapted to depend into said crucible with their lowermost ends in said remelting zone and having means for applying electrical power to said electrodes to melt the same, the improvement comprising: conduit means extending into said remelting zone of said crucible and including a slag conducting aperture communicating with said remelting zone, weld lug means pressed against a recess formed in the wall means of said crucible in the remelting zone thereof to provide electrical contact between said weld lug and said crucible, and an AC Power circuit including said electrodes, said power circuit having a current balancing line connected to said bottom plate whereby current flowing through said electrodes is increased or decreased by said current to maintain equal rates of melting of said electrodes.

Claim 50

In a furnace for electroslag remelting of metal having a crucible with wall means defining a remelting zone by the lower portion thereof and plural consumable electrodes adapted to depend into said crucible with their lowermost ends in said remelting zone and having means for applying electrical power to said electrodes to melt the same, the improvement comprising: conduit means extending into said remelting zone of said crucible and including a slag conducting aperture communicating with said remelting zone, weld lug means pressed against a recess formed in the wall means of said crucible in the remelting zone thereof to provide electrical contact between said weld lug and said crucible, and an AC Power circuit including said electrodes, said power circuit having a current balancing line connected to said bottom plate whereby current flowing through said electrodes is increased or decreased by said current to maintain equal rates of melting of said electrodes.

Claim 51

An electroslag refining furnace system as defined by claim 31, including a slag melting apparatus adapted to melt slag and deliver it to said fluid communicating means.

Claim 52

An electroslag refining furnace system as defined by claim 31, wherein said current supply means is adapted to supply melting current to said electrode means until an ingot of predetermined size is formed in said water cooled crucible means and to then terminate the supplied current, and wherein said system includes electrode holder means for moving said electrode means with respect to said crucible means.

Claim 53

An electroslag refining furnace system as defined in claim 31, wherein said electrode means comprises at least two electrodes and wherein said current supply means is adapted to supply melting current between said electrodes from the time the electrically conducting slag contacts said electrode means.

Claim 54

An electroslag refining furnace system as defined in claim 31, wherein said current supply means delivers alternating current to said electrode means.

Claim 55

An electroslag remelting furnace system comprising a receptacle for forming an ingot, said receptacle including a water cooled bottom plate and a separable water cooled crucible; a support column; electrode holding and moving means disposed on said supporting column adapted to support at least one electrode extending within said crucible with the lower electrode and initially disposed a predetermined distance from said bottom plate; electrical means for supplying current to said electrode holding means and an electrode when held by the same; fluid communicating means extending from the exterior to the interior of said ingot receptacle comprising channel means in the lower portion of said ingot receptacle, at least a portion of said channel means formed by an upper portion of said base plate and a lower portion of said crucible; and an upwardly extending pouring device outside said ingot receptacle in communication with said channel and extending vertically from the base plate a relatively short distance predetermined in relation to the spacing between said bottom plate and the lower end of an electrode when held by said holding means; said construction being such that molten slag poured into said upwardly extending pouring device flows by Gravity through said channel via a short path into the lower portion of said ingot receptacle creating therein a rising pool of molten slag that reaches a level sufficient to contact an electrode held by said holding and moving means and to cause current flow through the slag bath and any electrode held in said holding means when voltage is applied and when molten slag is poured from exterior to interior of said ingot receptacle.

Claim 56

An electroslag remelting furnace system comprising a receptacle for forming an ingot, said receptacle including a water cooled bottom plate and a separable water cooled crucible; a support column; electrode holding and moving means disposed on said supporting column adapted to support at least one electrode extending within said crucible with the lower electrode and initially disposed a predetermined distance from said bottom plate; electrical means for supplying current to said electrode holding means and an electrode when held by the same; fluid communicating means extending from the exterior to the interior of said ingot receptacle comprising channel means in the lower portion of said ingot receptacle, at least a portion of said channel means formed by an upper portion of said base plate and a lower portion of said crucible; and an upwardly extending pouring device outside said ingot receptacle in communication with said channel and extending vertically from the base plate a relatively short distance predetermined in relation to the spacing between said bottom plate and the lower end of an electrode when held by said holding means; said construction being such that molten slag poured into said upwardly extending pouring device flows by Gravity through said channel via a short path into the lower portion of said ingot receptacle creating therein a rising pool of molten slag that reaches a level sufficient to contact an electrode held by said holding and moving means and to cause current flow through the slag bath and any electrode held in said holding means when voltage is applied and when molten slag is poured from exterior to interior of said ingot receptacle.

Claim 57

An electroslag remelting furnace system as defined by claim 48, wherein at least a portion of said channel means is formed by a depression in said bottom plate, said depression at least in part covered by a lower portion of said separable water cooled crucible.

Claim 58

An electroslag remelting furnace system as defined by claim 49, wherein said channel means formed by said depression in said bottom plate extends from an exterior position to the interior of said ingot receptacle, said exterior position being spaced from the outer surface of said separable water cooled crucible.

Claim 59

An electroslag remelting furnace system as defined by claim 48, wherein at least a portion of said channel means is formed by an opening in the lower portion of said separable water cooled crucible.

Claim 60

An electroslag remelting furnace system as defined by claim 48, wherein at least a portion of said channel means is formed by both a depression in said base plate and an opening in said lower portion of said separable water cooled crucible and wherein said depression and said opening are in cooperating relationship.

Claim 61

An electroslag remelting furnace as defined by claim 48, further comprising at least one consumable electrode held by said electrode holding means.

Claim 62

An electroslag remelting furnace system as defined by claim 48, further comprising recess means formed in an interior wall of said ingot receptacle at the lower portion thereof; and weld lug means in and pressed against at least a portion of said recess means to provide electrical contact between said weld lug means and said ingot receptacle.