US3402250A

US3402250A - Water cooled electrode head for electric furnace electrodes or the like

Info

Publication number: US3402250A
Application number: US608668A
Authority: US
Inventors: Alfred H Turner
Original assignee: Individual
Current assignee: Individual
Priority date: 1967-01-11
Filing date: 1967-01-11
Publication date: 1968-09-17
Anticipated expiration: 1985-09-17

Description

Sept. 17, 1968 TURNER 3,402,250

WATER COOLED ELECTRODE HEAD FOR ELECTRIC FURNACE ELECTRODES OR THE LIKE Filed Jan. 11, 1967 2 Sheets-Sheet l Sept. 17, 1968 A. H. TURNER 3,402,250

WATER 000L131) ELECTRODE HEAD FOR ELECTRIC I FURNACE ELECTRODES on THE LIKE 2 Sheets-Sheet 2 Filed Jan. ll, 1967 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.) Filed Jan. 11, 1967, Ser. No. 608,668 3 Claims. (Cl. 13-16) ABSTRACT OF THE DISCLOSURE An electrode head having three angularly spaced water cooled contact shoes removably mounted on a clamping band and also on a second clamping member; a pair of electrically conductive water tubes connected to each shoe; a distribution header connected to the tubes and having passages therein for conducting the cool-ing water to and from the tubes.

The electrode head disclosed and claimed in this application may be regarded as an improvement upon the electrode heads disclosed in the copending Turner applications: Ser. No. 361,991, filed Apr. 23, 1964; and Ser. No. 584,216, filed Oct. 4, 196 6. Certain features disclosed and claimed herein are disclosed and claimed in the Turner Patent No. 2,997,511, patented Aug. 22, 1961.

This invention relates to electrode heads for electric furnace electrodes or the like. The basic purpose of such electrode heads is to supply electric current to the electrodes.

The Turner Patent No. 2,997,511 discloses a water cooled electrode head comprising an electrically conductive casting which is adapted to engage the electrode. An electrically conductive plate is mounted over a recess in the casting to form passages therein for conducting cooling water, or some other fluid coolant.

The Turner application Ser. No. 361,991 discloses a water cooled electrode head having two water cooled contact shoes removably mounted thereon. The Turner application Ser. No. 584,216 discloses a water cooled electrode head having one water cooled contact shoe removably mounted thereon.

Some of the general objectives of the present invention are to provide a new and improved electrode head in which the area of contact between the electrode and the contact shoes is increased substantially, without substantially increasing the size of the electrode head, so as to increase the current-carrying capacity of the electrode head, while minimizing the heat developed in the electrode head, so that the head will provide long, troublefree service.

A further objective is to provide a construction whereby the contact shoes may easily and quickly be removed and replaced in the field, without any need to remove the entire electrode head from its mast arm or other support. In this way, the cost of maintaining the electrode head will be minimized.

To accomplish these objectives, the present invention contemplates the provision of an electrode head having first and second clamping members which are relatively movable to clamp the electrode. The first clamping member includes a generally semi-circular clamping band. First and second contact shoes are removably mounted on the clamping band. The second clamping member includes a curved support, on which a third clamping shoe is removably mounted. Each shoe is formed with passages for conducting a fluid coolant such as water. Means are provided to carry the coolant to and from each shoe. Such means preferably comprises a pair of tubes connected to each shoe. The tubes preferably extend laterally to a dis- 3,402,250 Patented Sept. 17, 1968 tribution header having inlet and outlet openings for receiving and discharging the coolant. Passages are provided within the header to supply the coolant from the inlet opening to one tube of each pair, while discharging the coolant to the outlet opening from the other tube of each pair. The tubes also preferably conduct electric current to the shoes. Preferably, the first clamping member includes a pair of supporting portions connected to the opposite ends of the clamping band. Passages are formed in the supporting portions to conduct water or some other fluid coolant. The tubes are arranged so that the shoes may readily be removed from the electrode head, without removing the electrode head from its mast arm or other support.

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

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

FIG. 2 is an elevational view, the line 22 in FIG. 1.

FIG. 3 is a plan view of the clamping band and the clamping member on which it is mounted, the view being partly in section along the line 3-3 in FIG. 4.

FIG. 4 is an elevational view of the clamping member, partly in section along the broken line 44 in FIG. 3.

FIG. 5 is an elevational section, taken generally along. the line 5-5 in FIG. 4.

FIG. 6 is a fragmentary elevational section taken generally along the line 6-6 in FIG. 1.

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, for supplying electric current to the electrode. The electrode lread may also provide at least some of the support for the electrodes. 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 20 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 electric currents for such large electrodes are very high.

The illustrated electrode head 20 comprises first and second clamping members 24 and 26 which are relatively movable, for clamping the electrode 22. The first clamping member 24 comprises a generally semi-circular clamping band 28 which is preferably divided into upper and

lower portions

28a and 28b, with a slot or opening 30 therebetween. The clamping band 28 is preferably made of a corrosion-resistant material, such as stainless steel.

The second clamping member 26 is illustrated as comprising a cylindrically curved supporting member or plate 32 which is disposed in opposition to the clamping band 28. The curved support 32 is also preferably made of stainless steel or the like.

As illustrated, the first clamping member 24 comprises a body 34 on which the clamping band 28 is mounted. The body 34 is adapted to be mounted on the outer end of a mast arm 36 or other support. The mast arm 36 is normally fitted with a mounting flange 38 to which the body 34 is bolted or otherwise secured.

The illustrated body 34 comprises a rear wall or plate 40, adapted to be secured to the mounting flange 38. A lower Wall or shelf 42 is welded or otherwise secured to the rear wall 40.

partly in section along Side supporting members 46 are illustrated as being provided to support the clamping band 28. As shown, each side supporting member 46 is welded or otherwise secured to the rear wall 40. The side supporting members 46 extend forwardly and are connected to the opposite ends of the clamping band 28.

To dissipate excess heat, the side supporting members 46 are preferably provided with internal passages 48 for carrying cooling water or some other fluid coolant. To provide such passages, each side member 46 preferably comprises inner and outer walls or

plates

50 and 52. The inner plate 50 is shown as being formed integrally with the clamping band 28. The outer wall 52 is spaced outwardly from the inner wall 50 to form the water passages 48. The bottom wall or shelf 42 is preferably welded or otherwise secured to the

plates

50 and 52, so that the plate 42 closes the lower edges of the side supporting members 46. A top wall or plate 54 is welded or otherwise secured to each pair of

plates

50 and 52, so as to close the top edges of the side members 46. The rear wall or plate 40 preferably closes the rear edges of the side members 46. As illustrated, front walls 56 are welded or otherwise secured to the

plates

50 and 52, so as to close the front edges of the side members 46. Baffles 57 are preferably welded or otherwise secured between the inner and

outer plates

50 and 52, so as to force the cooling water to follow serpentine paths through the passages 48.

Openings 58 are formed in the side supporting members 46 to carry the cooling water into and out of the passages 48. Each of the illustrated openings 58 is formed in a boss or sleeve 60, extending upwardly from the corresponding side member 46. The openings 58 are adapted to receive hoses or other conduits 62, through which the cooling water is circulated into and out of the side supporting members 46. A cross tube 64 is preferably provided between the side members 46, to carry the cooling water therebetween. As shown, the cross tube 64 extends between the lower portions of the passages 48, just above the lower wall of shelf 42.

The second clamping member 26 is illustrated as being supported on the lower wall or shelf 42, for sliding movement therealong. In the illustrated construction, a lever 66 is preferably employed to move a second clamping member 26. The lever 66 is adapted to be operated by a hydraulic cylinder or the like. As shown, the lever 66 is swingable about a pivot 68 which is supported by brackets or lugs 70, welded or otherwise secured to the rear wall 40. The lugs 70 project forwardly from the rear wall 40.

The second clamping member 26 is preferably formed with a pair of rearwardly projecting lugs or brackets 72, 7

adapted to be connected to the lower end of the lever by means of a pivot pin 74. The lugs 72 are preferably welded to the curved support 32, or formed integrally therewith. The lever 66 projects forwardly from the pivot 68 to provide a long operating arm 76.

First and second contact shoes 81 and 82 are removably mounted on the curved clamping band 28. A third contact shoe is removably mounted on the curved supporting member 32. The

shoes

81 and 82 are disposed on the clamping band 28 with an angular interval therebetween. The third clamping shoe 83 is disposed in opposition to the

shoes

81 and 82.

As shown, the clamping

shoes

81 and 82 are removably secured to the clamping band 28 by means of bolts 86 which extend through openings 88 in the clamping band 28 and are tapped into corresponding openings in the

shoes

81 and 82. It will be understood that other fastening devices may be employed. The third electrode 83 is also preferably mounted on the curved member 32 by means of bolts 90.

To provide additional support, each of the

shoes

81 and 82 is also preferably provided with a flange or lip 92 which projects outwardly over the upper edge of the clamping band 28 and is adapted to be supported thereon.

Similarly, the shoe 83 is preferably provided with a flange 94 which projects outwardly therefrom and is adapted to be supported by the upper edge of the curved support 32.

As shown, blocks or spacers 96 are preferably welded or otherwise secured to the clamping band 28, for maintaining the spacing between the ends of the contact shoes 81 and 82.

Each of the contact shoes 8183 is formed with a passage 100 therein for carrying the cooling water or other fluid coolant. As disclosed and claimed in the previously mentioned Turner Patent No. 2,997,511, the passages 100' are preferably formed as recesses 102 in a cast body 104, made of copper or other highly conductive material. The recesses 102 are closed by curved plates 106 which are preferably welded to the body 104. Baffies 108 are provided so that the passages 100 will be serpentine.

The

shoes

81 and 82 are formed with

openings

110 and 112 which communicate with the opposite ends of the passage 100 therein. The illustrated

openings

110 and 112 extend horizontally into bosses 114 which project upwardly from the shoes 81 and S2. The shoe 83 is formed with upwardly extending

openings

116 and 118 which are connected with the opposite ends of the passage 100 therein.

The cooling water is preferably supplied to each of the shoes 81-83 by means of a pair of tubes, which also preferably carry the electric current to each shoe. Thus, the tubes are preferably made of copper or other highly conductive material.

In the illustrated construction,

tubes

120 and 122 are connected to the

openings

110 and 112 of the first shoe 81.

Tubes

124 and 126 are connected to the

openings

110 and 112 of the second shoe 82. Similarly,

tubes

128 and 130 are connected to the openings 11-6 and 118 in the third shoe 83.

As illustrated, all of the various tubes 120-130 are connected to a distribution header or block 132 which distributes the cooling water to the tubes. The header 132 also supplies the electric current to the tubes. As illustrated, the

tubes

120, 122, 124, 126, 128 and 130 are connected to

openings

140, 142, 144, 146, 148 and 150 in the header 132. Inlet and outlet openings 152 and 154 are also provided in the header 132. It will be understood that the inlet and outlet openings may be reversed.

The distribution header 132 is provided with passages -170 for distributing the cooling water from the inlet and outlet openings 152 and 154 to the various tubes 120430. For clarity, these passages 160170 are shown diagrammatically in FIG. 1 by means of broken lines with arrowheads. The

passages

160, 166 and 168 are connected between the inlet opening 152 and the

respective openings

140, 146 and 148. The

passages

162, 164 and 170 are connected between the outlet opening 154 and the

respective openings

142, 144 and 150.

The header 132 is adapted to be connected to a pair of

bus tubes

172 and 174 which supply the cooling water and the electric current to the electrode head. The

bus tubes

172 and 174 are preferably made of copper or some other highly conductive material. As shown to best advantage in FIG. 6, the header 132 is preferably clamped to the

bus tubes

172 and 174 by means of a member or plate 176 which is adapted to be secured to the header 132 by means of a plurality of bolts 178. Pipes or

conduits

182 and 184 are preferably connected between the

bus tubes

172 and 174 and the respective openings 152 and 154 in the header.

Unions

186 and 188 are preferably provided in the

pipes

182 and 184 so that the header 132 may readily be disconnected from the

bus tubes

172 and 174.

It will be seen from FIGS. 1 and 2 that the distribution header 132 is spaced laterally from the contact shoes 8183. The tubes 120-130 extend laterally between the shoes and the header. The tubes 120-430 are sufficiently long and flexible to provide for the slight clamping movement between the clamping members v24 and 26. It will be seen that all of the tubes 120-130 are spaced outwardly from the electrode 22. The tubes 120-126 for the contact shoes 81 and 82 are curved outwardly away from the electrode 2.2, and also away from the

other tubes

128 and 130.

The tubes 120-1'30 are arranged so that the contact shoes 81-83 may be removed very quickly and easily from the electrode head. Thus, as illustrated in FIGS. 1 and 2, the tubes 120-130 are removably connected to the distribution header 132 by means of end plates 190. Bolts 192 are employed to secure the plate 190 to the header 132. In addition, the

tubes

128 and 130 are connected to the contact shoe 83 by means of similar end plates 194 which are secured to the shoe by means of bolts 196.

The operation of the electrode head has already been described, but it may be helpful to olfer a brief summary. The electrode head 20 is clamped to the electrode 22 by swinging the lever arm 76 clockwise, as shown in FIG. 2, so as to apply clamping pressure between the electrode and the contact shoes '81, 82 and 83. The contact shoes conduct the electric current to the electrode. The tubes 120-130 carry the electric current to the shoes 81-83 from the header 132, which receives the current from the

bus tubes

172 and 174.

The

bus tubes

172 and 174 also supply cooling water or other fluid coolant. The water flows to and from the header 132 through the

pipes

182 and 184, and then to and from the shoes 81-83 through the tubes 120-130. Cooling water is supplied to the passages 48 in the side supporting members 46 through the hoses 62.

The three

contact shoes

81, 82 and 83 engage the electrode 22 around almost its entire periphery, so that a large total area of contact is provided between the electrode and the shoes. Thus, the electrode head affords a high current carrying capacity, while minimizing the heating of the shoes due to the passage of the electric current to the electrode.

The contact shoes '81-83 will last for a long time, but may eventually have to be replaced due to the effects of occasional arcing between the electrode and the shoes. It is an easy matter to remove the

shoes

81, 82 and '83 from the electrode head 20, without removing the electrode head from the mast arm 36. New contact shoes may be installed immediately, so that it is not necessary to send the electrode head back to the factory for rebuilding. The shoes 81-83 may be removed by unscrewing the

bolts

86 and 90 and disconnecting the tubes 120-130. The tubes are disconnected by removing the

bolts

192 and 194.

It will be evident that the electrode head may be maintained and serviced at extremely low cost. Moreover, new contact shoes may be installed very quickly so that the electrode head will be out of service for only a very short time.

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. An electrode head for a generally cylindrical electric furnace electrode or the like, comprising:

the combination of a base adapted to be disposed 0pposite one side portion of the electrode,

a generally semi-circular clamping band mounted on said base for extending around the electrode,

a curved clamping member movably mounted on said base opposite said clamping band,

first and second arcuate contact shoes mounted on said clamping band for engaging the electrode at angularly spaced points,

means for removably securing said first and second contact shoes to said clamping band,

a third arcuate contact shoe mounted on said curved clamping member for engaging the electrode in opposition to said first and second shoes,

means removably securing said third contact shoe to said curved clamping member,

a clamping mechanism for moving said curved clamping member relative to said base,

each of said shoes having inlet and outlet openings therein and a passage therein extending between said inlet and outlet openings for conducting a fluid coolant,

a plurality of electrically conductive tubes connected to all of said inlet and outlet openings in said shoes for carrying the fluid coolant to and from said shoes while also carrying electric current to said shoes, and

means removably securing said tubes to said shoes whereby said shoes may readily be removed from said electrode head.

2. An electrode head according to claim 1, including:

a coolant distribution header having inlet and outlet connections for receiving and discharging the fluid coolant to and from said tubes, and

means removably securing said tubes to said inlet and outlet connections on said header,

said header having passages therein for distributing the fluid coolant to all of said shoes.

3. An electrode head according to claim 1,

in which said base comprises a pair of side members connected to the opposite ends of said clamping band,

said side members having passages therein for conducting the fluid coolant, and

means for circulating the fluid coolant to and from said passages in said side members.

References Cited UNITED STATES PATENTS 1,335,895 4/1920 Hughes 13l8 2,632,780 3/1953 Whitehouse 13-16 3,026,444 3/1962 Slocombe et al. 1316 XR 3,072,732 1/ 1963 Maloney 13-16 BERNARD A. GILHEANY, Primary Examiner. H. B. GILSON, Assistant Examiner.