US3334170A

US3334170A - Water cooled electrode head for electric furnace electrodes or the like

Info

Publication number: US3334170A
Application number: US361991A
Authority: US
Inventors: Alfred H Turner
Original assignee: Individual
Current assignee: Individual
Priority date: 1964-04-23
Filing date: 1964-04-23
Publication date: 1967-08-01
Anticipated expiration: 1984-08-01

Description

Aug. 1, 1967 A. H. TURNER WATER COOLED ELECTRODE HEAD FOR ELECTRIC FURNACE ELECTRODES OR THE LIKE 3 Sheets-Sheet 1 Filed April 23, 1964 lzvvnvroe AL FRED H. Tun/v52 4rr'r$.

JAM/AM WATER COOLED ELECTRODE HEAD FOR ELECTRIC Aug. 1, 1967 A H. TURNER 3,334,170

FURNACE ELECTRODES OR THE LIKE Filed April 23, 1964 5 Sheets-Sheet 2 iii /NVEAITOR V5 \O 41.1mm H. TURNER L lj Aug. 1, 1967 A. H. TURNER WATER COOLED ELECTRODE HEAD FOR ELECTRIC FURNACE ELECTRODES OR THE LIKE 3 Sheets-Sheet :5

Filed April 23, 1964 R M TR r a. V 1 3 A n a Arrars.

United States Patent WATER COOLED ELECTRODE HEAD FOR ELECTRIC FURNACE ELECTRODES OR THE LIKE Alfred H. Turner, Pinson, Ala. (P.O. Box 1148, Birmingham, Ala. 35201) Filed Apr. 23, 1964, Ser. No. 361,991 Claims. (Cl. 13-16) This invention relates to new and improved electrode heads for use with electric furnace electrodes or the like. In various aspects, the present invention may be regarded as an improvement upon the invention disclosed and claimed in the prior patent of the present applicant, No. 2,997,511, issued Aug. 11, 1961.

One object of the present invention is to provide a new and improved electrode head having contact shoes which are adapted to engage the electrode, the contact shoes being readily removable and replaceable so that new contact shoes may be quickly and easily installed if the old shoes become damaged or worn.

A further object is to provide such a new and improved electrode head in which the contact shoes are formed with internal passages for the circulation of cooling water.

Another object is to provide such a new and improved electrode head in which the cooling water is supplied to the contact shoes by tubes or pipes which also carry the electrical current to the shoes.

A further object is to provide such a new and improved electrode head which is arranged so that the contact shoes may readily be disconnected from the cooling water tubes.

Another object is to provide a new and improved electrode head of the foregoing character in which the contact shoes are preferably fabricated from castings and plates which are made of copper and are welded together,

so as to form the cooling water passages within the shoes.

It is another object to provide such a new and improved electrode head in which the base or body of the head is also formed with internal passages for the circulation of cooling water.

A further object is to provide such a new and improved electrode head in which the contact shoes are preferably supported by curved bands which are secured to the body and are adapted to embrace the shoes.

Still another object is to provide such a new and improved electrode head which is highly economical, both as to original cost and the cost of maintenance, and which minimizes the time required for maintenance so that maintenance may be accomplished with a minimum loss of operating time.

Further objects and advantages of the present invention will appear from the following description taken with the accompanying drawings, in which:

FIG. 1 is a general plan view of an electrode head to be described as an illustrative embodiment of the present invention.

FIG. 2 is a side elevational view of the electrode head.

FIG. 3 is a fragmentary sectional view taken generally along the line 3--3 in FIG. 2.

FIG. 4 is a fragmentary enlarged horizontal section taken generally along the line 44 in FIG. 2.

FIG. 5 is an enlarged plan view with one of the contact shoes and a portion of the body of the head broken away and shown in horizontal section.

FIG. 6 is an enlarged side elevational view with portions of the head broken away and shown in vertical section.

FIG. 7 is a plan view of one of the contact shoes.

FIG. 8 is an elevational view showing the radially inward side of one of the shoes with portions broken away and shown in section.

ice

FIG. 9 is an elevationalview looking edgewise at one of the shoes.

FIG. 10 is a fragmentary somewhat diagrammatic sectional view taken generally along the line 10'--10 in FIG. 6.

As already indicated, the drawings illustrate an electrode head 20 for use with a cylindrical electrode 22 of an electric furnace or the like. It will be understood that an electric furnace employs a plurality of electrodes, and that each electrode is provided with a separate electrode head. The purpose of the electrode head 20 is to supply electrical current to the electrode 22 and also to provide at least some of the support for the electrode. Normally, the electrode 22 is made of carbon, either with or without a cylindrical sheath of metal. Typically, the electrode 22 and the electrode head are quite large. Thus, the particular electrode head 20 which is illustrated in the drawings is intended for use with an electrode having a diameter of 24 inches. Much larger electrodes and electrode heads are also frequently employed. It will be evident that the weight of such electrodes is quite great, and that the operating electrical currents for such large electrodes are very high.

The illustrated electrode head 20 comprises a body or mounting portion 24 which may be supported in the same manner as prior electrode heads. As shown, the body 24 is mounted on the outer end of a supporting arm 26.

The illustrated body 24 comprises a vertical backplate 28 and a pair of side members 30 which project from the opposite ends of the plate 28. The body 24 is adapted to be positioned opposite one side portion of the cylindrical electrode 22. v

The body 24 has upper and lower walls or plates 32 and 34 (FIG. 6) which extend between the side members 30 and are welded or otherwise secured to the backplate 28. The upper and

lower walls

32 and 34 also close the upper and lower ends of the side members 30.

As shown in FIGS. 1 and 2, the illustrated electrode 22 is provided with a pair of

curved bands

36 and 38 which extend between the side members 30 of the body 24 and are adapted to extend around the electrode 22. The opposite ends of the

bands

36 and 38 are welded or otherwise secured to the side members 30. The welds are clearly shown at 40 and 42 in FIG. 2.

The illustrated electrode head 20 is provided with two contact shoes 44 which are supported by the

bands

36 and 38 and are adapted to be pressed against the electrode 22. The shoes 44 serve the purpose of carrying the electrical current to the electrode 22. As shown in FIG. 1, a curved clamp 46 is provided to develop clamping pressure between the electrode 22 and the contact shoes 44. The clamp 46 is located between the side members 30 and the body 24 and is positioned opposite the contact shoes 44. As shown, the clamp 46 is mounted on the outer end of an operating plunger or shaft 48 which extends through a large central opening 50' in the backplate 28. The plunger 48 may be connected to a hydraulic cylinder or other similar device, not shown, which operates the clamp 46 and is adapted to move the clamp into and out of clamping engagement with the electrode 22. The plunger 48 extends along the length of the supporting arm 26 and is movable longitudinally relative thereto.

Two tubes or

pipes

50 and 52 are connected to each of the contact shoes 44 and are adapted to carry the electrical current to and from the shoes. In addition, the

tubes

50 and 52 carry cooling water which is ci-rculated through the shoes to keep the shoes cool enoughv to avoid damage to the shoes due to excessive heat. It will be understood that the shoes 44 are heated by the electrical current which passes between the shoes and the electrode. Moreover, the electrode transmits heat from the electric furnace to the shoes. As shown, the

tubes

50 and 52 are connected to a clamp 54 which in turn is connected to a pair of electrical bus bars 56. The

tubes

50 and 52, the clamp 54 and the bus bars 56 should be made of a material such as copper, which is highly conductive to electricity. Water pipes or hoses, not shown, may be connected to tapped

openings

58 and 60 in the ends of the

tubes

50 and 52.

Cooling water is also circulated through the body 24 of the electrode head 20. The side members 30 of the body 24 are hollow to provide for the circulation of the cooling water. As clearly shown in FIG. 10, a pipe or tube 62 is connected between the two side members 30 to conduct the cooling water therebetween.

It will be seen from FIG. that each of the side members has an outer wall 64 and an inner wall 66 which are spaced apart to form a passage or chamber 68 through which the water is circulated. The

walls

64 and 66 extend between the upper and

lower walls

32 and 34 and are welded or otherwise secured thereto. The backplate 28 closes the rear end of each chamber 68, while the front end is closed by a wall 70, as will be clearly evident from FIG. 5.

Each side member 30 is provided with an upper port 72 which is formed in the upper wall 32. A pipe or tube 74 may be connected to the port 72 to carry the cooling water. Each side member 30 also has a lower port 76 to which the interconnecting cross-pipe 62 is connected. The port 76 is formed in the lower portion of the inner wall 66.

In order to increase the cooling effect of the water, each chamber 68 may be provided with a plurality of

horizontal partitions

78, 79 and 80 which are arranged to force the water to follow a serpentine path in passing between the

ports

72 and 76. Thus, as shown in FIG. 6, the

partitions

78 and 80 extend to the left from the backplate 28 so that the water is forced to pass through openings 82 and 84 between the end wall 70 and the left-hand ends of the

partitions

78 and 80. On the other hand, the intermediate partition 79 extends to the right from the end wall 70 so that the water is forced to pass through an opening 83 between the backplate 28 and the righthand end of the partition 79.

The cooling water is caused to flow into the body 24 of the electrode head 20 through one of the connecting pipes 74, while the water flows out of the body 24 through the other pipe 74.

As already indicated, cooling water is circulated through each of the contact shoes 44. To provide the necessary water passages, each shoe 44 is preferably constructed in accordance with the invention disclosed and claimed in the :applicants prior patent, No. 2,997,511, patented Aug. 22, 1961. Thus, each of the illustrated shoes 44, comprises a curved member 86, preferably a casting, to which a curved plate 88 is welded. The plate 88 forms the inner wall of the shoe 44 and has a cylindrically curved surface 90 which engages the outside of the electrode 22. The plate 88 may be a cast member but it usually is formed of rolled metal. Both the casting 86 and the plate 88 should be made of a material such as copper which is highly conductive to both electricity and heat.

The casting 86 is formed with a channel or cavity 92 which is closed by the plate 88 to form the passage or chamber through which the cooling water is circulated. To improve the effectiveness of the cooling water, a rib or partition 94 is formed on the casting 86 so as to bring about a partial subdivision of the cavity 92, so that the water has to flow along a curved path of considerable length in passing through the contact shoe. As clearly shown in FIG. 8, the partition 94 extends downwardly into the cavity 92 so as to force the water to pass through a restricted opening 96 between the lower end of the partition 94 and the lower end of the cavity 92.

The plate 88 covers most of the inside of the contact shoe 44, as will be apparent from FIG. 8, but the shoe has an upper portion 98 which extends above the plate and is flush with the exposed surface of the plate. The upper portion is formed with two

ports

100 and 102 which communicate with the upper end of the cavity 92 on opposite sides of the partition 94. The illustrated

ports

100 and 102 are downwardly tapered, for receiving the correspondingly tapered

end portions

104 and 106 of the

tubes

50 and 52. Rather than being threaded or screwed into the

ports

100 and 102, the

tapered portions

104 and 106 of the tubes are clamped into the ports so as to facilitate the connection and disconnection of the tubes from the contact shoes. Thus, each of the

tubes

50 and 52 is provided with a clamping plate 108 which engages an enlargement or shoulder 110 which is formed on the tube just above the tapered end portion. The plate 108 is formed with an opening 112 through which the tube extends. A plurality of bolts or screws 114 are employed to draw the plate 108 downwardly toward the contact shoe 44 so that the plate will clamp the tapered end portion of the tube into the corresponding port. Tapped openings 116 are provided in the shoe 44 to receive the threaded lower ends of the bolts 114.

Cooling water may be supplied under pressure by the tube 50 and may pass through the port 100 into the cavity 92. The water passes out of the cavity 92 through the port 102 into the other tube 52.

It will be seen that the

bands

36 and 38 embrace the contact shoes 44 and are effective to press the shoes against the electrode 22. Moreover, the shoes are supported by the upper band 36. Each shoe has an outwardly projecting flange 118 at its upper end. The lower side of the flange 118 engages the upper edge of the band 36 so that the band 36 prevents each contact shoe from moving downwardly relative to the electrode head. Each shoe is retained against upward movement by a clamping plate 120 which is secured to the shoe by a bolt 122. A tapped opening 124 is formed in the outer side of each shoe to receive the bolt 122. It will be seen that the clamping plate 120 has a shoulder 126 which engages the lower edge of the band 36 and prevents the shoe from moving upwardly relative to the band. The clamping plate 120 also has a reduced end portion 128 which overlaps the band 36 and securely clamps the outside of the shoe against the inside of the band.

The plate or inner member 88 of each contact shoe 44 is preferably welded to the casting or outer member 86. The weld extends around all four edges of the plate 88 and is clearly shown at 130 in FIG. 6. As shown, the weld 130 is in the form of a V-shaped bead of metal which is flush with the surface of the contact shoe.

As already indicated, the contact shoes 44 are preferably made of a material such as copper which is highly conductive to both electricity and heat. However, the body 24 of the electrode head 20 does not have to conduct electrical current and may be made of a material such as stainless steel which is extremely strong and resistant to corrosion. The

bands

36 and 38 may also be made of stainless steel or similar material.

By means of bolts 132 or otherwise, the backplate 28 may be secured to a mounting plate 134 on the outer end of the supporting arm 26. Holes 134' are formed in the backplate to receive the bolts.

It has been found that most of the wear, resulting from normal use of the electrode head, is concentrated at the contact shoes 44. Occasionally, the contact shoes may need to be repaired or replaced. With the construction of the present invention, each of the contact shoes 44 may easily be removed from the electrode head so that a new shoe may be installed. The shoes may be changed in a short time, so that the interruption in the operation of the electric furnace is minimized. Each shoe may be removed by loosening the main clamp 48, disconnecting the tubes 50' and 52 from the shoe, and removing the clamping bolt 122, whereupon the shoe may be slid upwardly and removed from the

bands

36 and 38. The

tubes

50 and 52 are disconnected by removing the bolts 114 from the clamping plates 108. The bus bar clamp 54 may be loosened to permit the

tubes

50 and 52 to be moved out of the way of the shoe, so that it may be slid upwardly out of the electrode head 20. Thus, a worn shoe may be removed and replaced with a new shoe in a very short time. The worm shoe may then be repaired or rebuilt for additional service in the future. Normally, the stainless steel body 24 and

bands

36 and 38 will last indefinitely and do not need to be repaired or replaced.

It will be evident that the electrode head of the present invention is efiicient and highly servicable. Moreover, it is economical and may be repaired very easily and quickly. Thus, the electrode head provides very low operating and maintenance expenses.

Various other modifications, alternative constructions and equivalents may be employed without departing from the true spirit and scope of the invention, as exemplified in the foregoing description and defined in the following claims.

I claim:

1. In an electrode head for use with cylindrical electric furnace electrodes or the like,

the combination comprising a body adapted to be positioned opposite one side portion of the electrode,

said body comprising a backplate and a pair of side members projecting therefrom,

a pair of curved bands extending between said side members and adapted to extend around the electrode,

a pair of contact shoes mounted on said bands and adapted to engage the electrode to carry electrical current to the electrode,

means securing each contact shoe to at least one of the bands,

a clamping device engageable with the electrode between said side members on said body for clamping said contact shoes against the electrode,

a pair of tubes extending to each of said shoes for carrying electrical current to the shoes and also for conducting cooling water to and from the shoes,

and means for disengageably connecting said tubes to said shoes,

each of said shoes comprising a curved casting and a curved plate welded to said casting,

said casting and said plate having passages for carrying cooling water therebetween.

2. In an electrode head for use with cylindrical electric furnace electrodes or the like,

said body comprising a back member and a pair of side members projecting therefrom,

said side members being formed with passages for the circulation of a cooling medium,

a pair of contact shoes mounted against the inside of said bands and adapted to engage the electrode to carry electrical current to the electrode,

each shoe having an outwardly projecting member resting upon the upper edge of one of said bands,

a clamp forremovably securing each shoe to one of said bands,

each shoe comprising curved inner and outer members welded together,

one of said members having channels therein forming passages between said members for the circulation of a cooling medium,

a pair of tubes extending to each of said shoes for carrying electrical current to the shoes and also for conducting the cooling medium to and from the shoes,

and means for removably connecting said shoes to the corresponding tubes.

3. In an electrode head for use with cylindrical electric furnace electrodes or the like,

said body being formed with passages for the circulation of a cooling medium,

a plurality of curved bands extending between said side members and adapted to extend around the electrode,

a plurality of contact shoes mounted against the inside of said 'bands and adapted to engage the electrode to carry electrical current to the electrode,

each shoe having an outwardly projecting member resting upon the upper edge of one of said hands,

a clamp for removably securing each shoe to at least one of said bands,

each shoe having passages therein for the circulation of a cooling medium,

a plurality of tubes extending to each of said shoes for carrying electrical current to the shoes and also for conducting the cooling medium to and from the shoes,

and means for removably connecting said shoes to the corresponding tubes.

4. The combination of claim 3, in which each clamp engages both of said bands and is connected to the corresponding shoe between said bands.

5. In an electrode head for use with cylindrical electric furnace electrodes or the like,

said body being formed with passages for the circulation of a cooling medium,

a plurality of contact shoes mounted against the inside of said bands and adapted to engage the electrode to carry electrode current to the electrode,

means for removably securing each shoe to at least one of said hands,

each shoe having passages therein for the circulation of a cooling medium,

and means for removably connecting said shoes to the corresponding tubes.

References Cited UNITED STATES PATENTS 2,475,209 7/1949 Tucker 219-120 2,716,145 8/ 1955 Cartoux 13-46 2,997,511 8/1961 Turner 13--15 FOREIGN PATENTS 122,034 1/ 1919 Great Britain.

JOSEPH V. TRUHE, Primary Examiner.

Claims

1. IN AN ELECTRODE HEAD FOR USE WITH CYLINDRICAL ELECTRIC FURNACE ELECTRODES OR THE LIKE, THE COMBINATION COMPRISING A BODY ADAPTED TO BE POSITIONED OPPOSITE ON SIDE PORTION OF THE ELECTRODE, SAID BODY COMPRISING A BACKPLATE AND A PAIR OF SIDE MEMBERS PROJECTING THEREFROM, A PAIR OF CURVED BANDS EXTENDING BETWEEN SAID SIDE MEMBERS AND ADAPTED TO EXTEND AROUND THE ELECTRODE, A PAIR OF CONTACT SHOES MOUNTED ON SAID BANDS AND ADAPTED TO ENGAGE THE ELECTRODE TO CARRY ELECTRICAL CURRENT TO THE ELECTRODE, MEANS SECURING EACH CONTACT SHOE TO AT LEAST ONE OF THE BANDS, A CLAMPING DEVICE ENGAGEABLE WITH THE ELECTRODE BETWEEN SAID SIDE MEMBERS ON SAID BODY FOR CLAMPING SAID CONTACT SHOES AGAINST THE ELECTRODE, A PAIR OF TUBES EXTENDING TO EACH OF SAID SHOES FOR CARRYING ELECTRICAL CURRENT TO THE SHOES AND ALSO FOR CONDUCTING COOLING WATER TO AND FROM THE SHOES, AND MEANS FOR DISENGAGEABLY CONNECTING SAID TUBES TO SAID SHOES, EACH OF SAID SHOES COMPRISING A CURVED CASTING AND A CURVED PLATE WELDED TO SAID CASTING, SAID CASTING AND SAID PLATE HAVING PASSAGES FOR CARRYING COOLING WATER THEREBETWEEN.