DE2242154A1 - UNITED ELECTRODE HOLDER AND ARM FOR ELECTRODES IN ELECTRIC ARC FURNACE OR THE LIKE - Google Patents

Description

Mr, '- ·. ·. ·. ·· 22Λ2154

r.! -, ¹ " ^. · '"",. ·: August 24, 1972

Gzh / goe

Edgar Wunsche, 406 Rosmere Street, Ostiawa, Ontario Canada Alfred H. Turner, Lewis H. Durdin, P.O. Box 1148, Birmingham, Alabama, 35201 U.S.A.

Combined electrode holder and arm for electrodes in electric arc furnaces or the like.

The invention relates to electrode holders for electrodes in electrical Arc furnace or the like. The electrode holder is preferably combined or combined with a carrying arm

It is an object of the invention to provide a new and improved electrode holder which is a contact member or shoe having that from a busbar or tube rait electrically Power is supplied, with / uic busbar longitudinal extends into the tubular support arm. In known arrangements it has been found that a large amount of heat is contained in the tubular Support arm is generated as a result of eddy currents generated by the magnetic field around the busbar tube will.

According to the present invention, such heating of the support arm is prevented by the busbar tube with a Shielding tube made of a material with high electrical conductivity is surrounded. The busbar tube is from the Ab ™ shielding tube electrically isolated, although a connection

309 8 1 07.0 79 4 _βΛπ

BATH

between one end of the busbar tube and one end of the Shielding tube would be permissible under appropriate conditions. The shield tube is preferably also from the support arm isolated, although connection between one end of the shield tube and the corresponding end of the support arm is permitted is if the shield tube were isolated from the busbar tube. The shield tube limits the magnetic Field around the busbar tube to the space between the busbar tube and the shield tube. Therefore switches the shield tube eliminates any mutual inductance or coupling between the busbar tube and the support arm Shield tube also eliminates mutual inductance or coupling between the busbar tubes of adjacent ones Electrode holder.

In a conventional electric furnace, different electrodes are attached to a corresponding number of electrical holders worn, which connect the electrodes to the different phases of an electrical multi-phase system. The shielding tube minimizes the mutual inductance between the different phases. Such inductance can cause trouble Give rise to the fact that it creates conditions of imbalance in respect of this of the currents supplied to the electrodes by the different phases. The resulting inequality

309810/0794

224215 «

the heating generated by the various phases is minimized by the present invention.

The support arm is preferably made of non-magnetic, stainless steel Steel or other non-magnetic material of high strength. The use of a non-magnetic Materials avoids the heating that occurs in a magnetic material due to hysteresis effects due to the magnetic FeI. that could be generated around the electrodes.

Further advantages and possible uses of the invention result from the attached representation of execution ~ examples as well as from the following description.

Show it:

Fig. 1 is a longitudinal section through a united · Electrode holder and arm,

Fig. 2 is an external end view taken along line 2-2, in Fig.

Fig. 3 is a vertical section through the arm along the .Linie 3-3 in Fig. 1,

30981 0/0794

4 shows a horizontal longitudinal section through electrode holders and arm, and

FIG. 5 is a vertical section along the line 5-5 in FIG.

The drawings illustrate a combined arrangement of an electrode holder and arm Io for painting a cylindrical one Electrode 12 as could be used in an electric arc furnace or the like. The unit Io has a Clamp assembly 14, which is attached to the outer end of a support arm 16 is attached.

The clip assembly 14 is annular and extends aich uin the electrode 12. The clamp assembly has a contact member d of the shoe 17 to deliver electrical current to the electrode 12 to deliver. The contact shoe 17 is made of copper or other material of high electrical conductivity. From Fig. 4 is to It can be seen that the contact shoe 17 has a cylindrically curved surface 18 for receiving the electrode 12. Coolant passages 2o are preferably formed in the contact shoe to allow the circulation of cooling water or another cooling liquid to allow. The coolant passages 2o can be produced by drilling or in some other way. However it is particularly advantageous to have the coolant flow in in the manner described in U.S. Patent No. 2,997,511.

309810/0794

BATH. ORIGINAL

_ ₅ _ 22Α2Ί 54

The clamp arrangement 14 has a device for generating a clamp pressure between the electrode 12 and the contact shoe 17. As shown, the clamp pressure is generated by a movable clamp member or shoe 22, which is opposite your Kentaktschuh 17 is attached to a clip band 24. However, the contact shoe 17 could just as well be movable to the ■ Generate clamp pressure.

In this case, the force on the staple shoe 22 is by means of

a device 26 which can be actuated by fluid pressure is generated, which consist of a piston 28! is shown, which is movable in a cylinder 3o and sealed by a bellows 32 is. Hydraulic fluid or other pressurized fluid Liquid is supplied to the cylinder 3o from a conduit 34 which is connected to a passage 36 leading into the cylinder. connected is. The illustrated fluid pressure actuated arrangement generates the clamp pressure, which is just as good from a fire could be applied and operated by the liquid pressure Order to be canceled, or. could be reversible.

The clip band 24 is double-walled to passages 38 for the Circulation of water or another cooling liquid create. Coolant passages 4o can also be found in the Klamiaerschuh 22 may be provided. As indicated in FIGS. 1 and 2,

30 fl H-10/0794

bath

Flexible lines 42 can be used to ground the cooling liquid to lead to the clamp shoe 22 and away from it. Such flexible lines are preferably made Metal to withstand the heat that occurs.

The illustrated support arm 16 is tubular and preferably made of non-magnetic stainless steel or a non-magnetic material of high strength. The usage of non-magnetic material avoids Ilysteresis losses in the support arm. The support arm is preferably double-walled to provide passages 44 for the circulation of a liquid / food coolant to accomplish. As best seen in Fig. 3, the illustrated bracket 16 has a rectangular outer Viand or tube 46 and a cylindrical inner wall or tube 48.

The clamp band 2 <i is welded to the outer end of the support arm 16 or fastened in some other way, as can be seen from FIG. The contact shoe 17 is also attached in a suitable manner to the outer end of the support arm 16. As shown, a mounting plate or member 5o is attached to the support arm 16 to support the contact shoe 17.

BAD ORIGINAL 3 Cl ^e ) H 1 ^{0/0 7 r} ) A

Means are preferably provided to isolate the contact shoe 17 from the support arm 16 and the clip band 24. As shown in Figs. 1 and 4, thin members 52 of electrical serve insulating material for this purpose.

Electric current is supplied to the contact shoe 17 from a busbar tube 54, which extends within the hollow, tubular support arm 16. This arrangement of the Busbar tube provides a very compact construction. It can be seen that the busbar tube 54 extends longitudinally in the support arm 16 and has a portion 56, which extends beyond the inner end of the support arm. A link 58 is attached to the protruding part 56 stigt and can be connected to one or more flexible cables leading to a source of electrical power. The busbar tube 54 and connector 58 are made of copper or some other high electrical material Conductivity.

The bus bar 54 could be solid, but is preferred tubular to provide a passage 6o for the circulation of a cooling water or any other cooling liquid. The passage 6o is preferably used to carry the cooling liquid to the contact shoe 17 or away from it.

30 9 8 10/0794

An additional conduit or tube 62 is preferably provided, to close the circuit for the circulation of the cooling liquid to the contact shoe 17 and away from it. As shown, the coolant line 6 2 is coaxial within the Stroitischienenröhre 54 arranged. The busbar tube 54 preferably lies axially in the support arm 16.

In accordance with the present invention is a shield tube 64 around the busbar tube 54 and within the tubular support arm 16. The shield tube 64 is made of copper or some other material high electrical conductivity. Other examples of such high conductivity materials are silver and highly conductive Aluminum. The busbar tube 54 and the shut-off tube 64 are preferably cylindrical and coaxial. The high conductivity shield tube acts as an effective magnetic shield around the busbar tube 54, so that the magnetic field around the busbar tube affects the space between the Stroiuschienenröhre 54 and the shield tube 64 is limited. Therefore, the shield tube 64 eliminates electromagnetic induction or coupling between the stroke rail tubes 54 and the tubular support arm 16. Without this divider tube 64, such electromagnetic induction would produce eddy currents of a very considerable magnitude in the metal walls of the support arm 16

309010/0794

cause. These eddy currents cause the Support arm, so that a lot of energy is uselessly consumed. In addition, the heating can be so great that it is destructive works. ,

The shielding effect of the highly conductive tube 64 is due to the circulating currents that flow in the shield tube induced by the magnetic field around the busbar tube 54. Due to the high conductivity of the shield tube 64, the currents generated by them are circulating To dissipate heat small and without difficulty from the cooling water or another cooling liquid.

The shield tube 64 is preferably from the busbar χ-eye 54 isolated, although a connection could be allowed on one end. As shown is the shield tube isolated from busbar tube 54 at both ends and at intermediate points. At the end of the shield tube 64 next to the contact shoe 17, the shielding tube is electrical isolated from the contact shoe and the busbar tube 54 by means of a thin insulating layer or member 66. At the opposite or inner end of the support arm 16 is the shield tube 64 by means of an annular support member or insulator 68, which consists of a heat-resistant

3 ϋ Π H 1 O / O 7 ¹ U

^{& AD}

22A2154

- Io -

insulating material. It can be seen that the shield tube 64 is inserted into a bore 7o in the insulator 68 is fitted. Another bore 72 is formed in the insulator 68 to receive a collar 74 which extends around the protruding End portion 56 of the busbar tube 54 is arranged. The insulator 68 is screwed to the support arm 16 or on other V / eise attached.

The shield tube 64 is also preferably isolated from the tubular support arm 16, although an electrical one Contact at one end is allowed. In this case, the protruding end of the shield tube 64 is adjacent to the insulator 68 electrically isolated from the support arm 16 by means of an insulating member 76. At the end of the illustrated shielding tube 64 In addition to the contact shoe 17, the shielding tube 64 is by means of a collar 78 connected to the support arm 16, the collar 78 as a spacer between the shielding tube 64 and the inner wall 48 of the tubular support arm 16 acts.

The highly conductive shield tube 64 essentially eliminates any electromagnetic coupling between the power rail tube 54 and the support arm 16 so that the current in the power rail tube does not induce currents in the support arm. This eliminates the heating that would be caused by such induced stresses.

0 9 8 10/0794 ^BAD ORIGINAL

- left - ■

In addition, the shield tube 64 substantially eliminates any electromagnetic induction between the busbar tubes of adjacent support arms in the case of ordinary electrical ones Ovens that use multiple support arms to hold different electrodes of a multi-phase electrical system. Switching off the electromagnetic coupling between the busbar tubes of the various phases avoids difficulties which could be caused by this coupling, so the coupling between the phases can balance the'between the currents of the individual phases should exist. This would cause the heat to be dissipated by the electrodes of the different phases is generated is unequal. The shield tube of the present invention eliminates or greatly reduces such inequalities.

It can be seen that a space 8o is created between the shield tube 64 and the inner wall 48 of the support arm. cooling water or some other cooling liquid preferably circulates through room 8o. Cooling water could also pass through the space 82 between the busbar tube 54 and the shield tube 64 circulate, but this is usually not necessary and can mean losses due to currents in the water induced by the intense magnetic field in this room.

309810/0794

ORIGINAL INSPECTED

Using the shielding tube of the present invention there is no heating of the support arm as a result of currents that are induced by the conductor rail tube. Therefore the support arm is protected against damage from excessive heating.

The arrangement of the busbar tube within the support arm provides a very compact construction, which makes it possible to to group the electrodes of the different phases in a pitch circle of small purchmessers. The more compact construction reduces the mechanical stresses, the structure and the costs of maintenance.

3098 10/07, U

Claims (18)

- 13 claims 1.7 Electrode holder for the electrode of an electric furnace or the like, du-RCH in an annular Klammeranordnuny _r which can be arranged around the electrode, and has a contact Shah for making electrical contact with the electrode, which consists of a material of high electrical conductivity, and which includes means for applying a clamping pressure between the electrode and the contact shoe, through a hollow tubular support arm mechanically connected to the clamp assembly for delivering a support for the electrode and the Hlamneranordnurig, through a bus bar electrically connected to the contact shoe is connected and extends longitudinally in the hollow tubular support arm ■ to transmit electrical current ζum contact shoe, and which is made of a material of high electrical conductivity, through a shield tube that extends around the bus bar and longitudinally in the hollow len tubular support arm is arranged und.aus a non-magnetic material of high electrical conductivity to create a magnetic shield between the busbar and the support arm, whereby the 3 O η 3 1 O / O 7 3 U Support arm against heating due to eddy currents which are induced due to the current in the busbar, is protected, and by Isolierungsiaittel for Creation of electrical insulation between at least one end of the busbar and the corresponding end of the Shield tube and for providing electrical insulation between at least one end of the shield tube and the corresponding end of the support arm. 2. Electrode holder according to claim 1, characterized in that that the shield tube is made of copper. 3. Electrode holder according to claim 1, characterized in that that the shield tube is made of aluminum. 4. Electrode holder according to one of the preceding claims, characterized in that the busbar ordered from copper. 5. Electrode holder according to one of the preceding claims, characterized in that the contact shoe £ ius consists of copper. 6. electrode age according to one of the preceding claims, characterized by deiß dor 309310/079 / » BATH ORIGINAL ■ »15 - · Support arm consists of a non-magnetic material of high strength. 7. Electrode holder according to one of the preceding claims, characterized in that the support arm is made of non-magnetic, stainless steel. 8. Electrode holder according to one of the preceding claims, characterized in that · that the busbar and the shield tube are cylindrical. 9. Electrode holder according to one of the preceding claims, characterized in that the busbar and the shield tube are coaxial. 10. Electrode holder according to one of the preceding claims, characterized in that the busbar and the shield tube are coaxial with the support arm lie. 11. Electrode holder according to one of the preceding claims, characterized in that the busbar has the shape of a tube. 309810/0 7 9 4 12. Electrode holder according to one of the preceding claims, characterized in that the Busbar from the contact shoe through the entire length of the Support arm extends and has a device which vpr behind the end of the support arm and has means, Hum connecting the busbar to an electrical power source, the / ibschirroungsröhre ura the busbar extend into the support arm. ¹ 13. Electrode holder according to one of the preceding claims, characterized in that the insulation device has an insulator which is mounted on the support arm and forms a support for a connector on the busbar and the corresponding end of the connection tube. 14. Electrode holder according to one of the preceding claims, characterized in that the insulating device a device that provides electrical insulation for aera contact shoe and the i Trogarm hers Lelit. 15 .. electrode holder according to one of the preceding claims, characterized by a facility to circulate a Kuhliuitl.al.il ussiykcit. through ■ the mcranordnung ,, the contact shoe, uie busbar and uen Beam. au * * 10 / ov.η 16. Electrode holder according to one of the preceding claims, characterized in that the Clamp assembly comprising means to exert a clamp force to apply against the electrode opposite the contact shoe. 17. Electrode holder according to one of the preceding claims, characterized in that the KlaiPiaerordnung a clasp link to engage with the electrode facing the contact shoe on v / eist and an actuator for developing a clamp force against the clamp member to produce a clamp pressure between the clamp member and the electrode and also between the electrode and the contact shoe to create. 18. Electrode holder according to claim 17, d a through g e ~ indicates that the actuator a liquid operated device is under development a clamp force against the clamp member, for application a Klciumordruckes between dom Klcimmer member and the Electrode and also between the electrode and the contact shoe. ORIGINAL 30 9?) I 0/07;) A