US2441416A - Cooled electrode for metal heating - Google Patents

Description

y 1948. R. K. HOPKINS 2,441,416

COOLED ELECTRODE FOR METAL HEATING I Filed June 1, 1945 2 Sheets-Sheet l ummmmxmxqrmxaxmm ATTORNEY y 11, 1948- R. K. HOPKINS 2,441,416

COOLED ELECTRODE FOR METAL HEATING Filed June 1, 1945 2 Sheets-Sheet 2 37 I INVENTOR 5 KObePZKHO I/ZMS BY- ATTO R N EY Patented May 11, 1948 2,441,416 v COOLED ELECTRODE ron METAL HEATING Robert K. Hopkins, New York, N. Y., assignor to The M. W. Kellogg Company, New York, N. Y., a corporation of Delaware Application June 1, 1945, Serial No. 596,992

3 Claims.

The present invention relates to an electrode device adapted especially for use in conjunction with casting operations.

After molten metal has been deposited in a mold, it may be desirable to heat thismetal in order to control its solidification and/or to hottop" it, i. e., maintain the top portion of the metal fluid until the last to feed and fill the shrinkage cavity below. For that purpose, one or more non-consumable electrodes may be lowered into the filled mold until the lower ends of the electrodes are immersed in a floating layer of slag or flux, and are spaced above the top of the deposited metal by gaps of predetermined length. Current of suitable intensity discharged across these gaps effects the necessary heating of the deposited metal. During this heating operation, the deposited metal shrinks and its level gradually falls. The electrodes are mounted for downward movement in order to maintain these current discharge gaps substantially constant in length as the metal level falls.

In one type of electrode hot-topping device employed, the electrodes are of metal and hollowed to permit cooling by a liquid such as water. Therefore, conduit means must be provided to deliver cooling liquid to and from the electrode device during hot-topping operations. This conduit means usually takes the form of long flexible hose which are cumbersome, and which are a source of annoyance and trouble because of loose connections, fouling, etc. The use of water in longconduits is also undesirable because of the tendency of this water to freeze during the winter while not in use in an open shop.

One object of the present invention is to provide a new and improved electrode device which has no long cumbersome hose connections, and which includes a compact, self-contained, circulatory unit comprising a motor-driven pump and one or more liquid-cooled electrodes.

In accordance with certain features of the present invention, the electrode device includes a portable head having a receiver, a motor driven pump, and one or more liquid-cooled depending electrodes, all closely united into a compact self-contained unit. This unit is connected by a beam or'arm to a hoist by which the electrodes may be moved up and down with respect to a mold in which the hot-topping operations are to be carried out.

Various other objects, features and advantages of the invention will be apparent from the following particular description, and from an inspection of the accompanying drawings, in which:

Fig. 1 is a top plan view of an electrode device embodying the present invention, and shown in connection with a mounting for said device and with molds in which hot-topping operations are adapted to be carried out by said electrode device, said device being shown positioned in readiness for hot-topping operations;

Fig. 2 is a view partly in side elevation and partly in vertical section of the arrangement shown in Fig. 1;

Fig. 3 is a view partly in side elevation and partly in vertical section of the arrangement shown in Fig. 1, the electrode device, however, being shown in inoperative retracted position; and

Fig. 4 is a vertical section of the electrode circulating system of Fig. 2, but on an enlarged scale.

Referring to the drawings, there is shown a plurality of molds |0, which may be of any suit" able shape or design according to the desired shape of the metal to be produced, and which may be of any suitable material from which molds are usually made, such as cast iron.

The cast metal H is produced in any-manner and deposited in molten condition in the mold l0 until the desired level therein has been reached. The metal ll may be deposited underneath a protective layer of flux or slag l2, or if desired, this flux may be charged into the molds l0, after they have been filled to the desired levels with molten metal I I.

My new and improved electrode device for hot-topping metal in molds such as those described, has a head l4 comprising a receiver [5, a motor-driven pump it for circulating a cool ing liquid in and out of said receiver, and one or more non-consumable electrodes I! connected to and depending from said receiver, all of said members being closely united into a compact selfcontained unit. Although only two electrodes I! are shown, a number of these may be provided forming a so-called sunflower group.

The receiver I5 'is desirably provided with radiating fins 20, and is divided by a substantially horizontal partition 2! into two superposed compartments 22 and 23. The upper wall of the receiver l5 has a hole 24 through which the electrode circulating system may be emptied or filled with a suitable cooling liquid 25 such as water. This hole 24 is normally closed by a screw plug 26.

The bottom receiver wall 21 has a substantially horizontal bed-plate extension 28 on which is mounted an electric motor 29 for driving the pump l6. Motor 29 has its frame directly connected to the casing of the pump IE to form a small compact power pump unit. Pump it, which may be of the rotary type, has an outlet connection 30 joined to the inlet of the upper receiver compartment 22 and an inlet connection 3| joined to the outlet of the lower receiver compartment 23.

Each electrode i1 is of a. material having high heat conductivity such as copper, and comprises an outer shell 35 closed at the bottom by a substantially hemi-spherical tip and connected at its upper open end to the lower side of the lower receiver compartment 23, as for example, by a threaded connection to the bottom receiver wall 21. Extending into each electrode I1 is a slender open-ended pipe 36, concentric with the outer shell 35 and forming therewith an annular flow chamber 31. The lower end of this inner pipe 36 is spaced a short distance from the lower end of the outer shell 35. The upper section of this inner pipe 36 passes through the lower receiver chamber 23 and through the partition 2|, is secured to said partition, as for example, by a threaded. connection thereto, and opens into the upper receiver compartment 22 for communication therewith.

By means of the arrangement described, cooling liquid flows from the upper receiver compartment 22 into the upper ends of the inner electrode pipes. 35 and downwardly through said pipes. The cooling liquid is discharged from the lower ends of inner electrode pipes 36 directly against the hottest parts of the electrodes I! at the lower tips of their outer shells 35, and is returned upwardly through the outer flow chambers 31 into the lower receiver compartment 23.

The compact, self-contained power pump, circulating electrode unit I4 described is mounted through a substantially horizontal beam 40 to a hoisting device 4|, located in a pit or housing 39, which raises and lowers said unit. In the specific form shown, the bed plate 28 of the electrode unit l4 is connected to beam 40, which in turn is slidable in a cross-head 42, and which is locked in adjusted slide position in said cross-head by a locking screw 43. The cross-head 42 is connected to one end of an oblique arm 44, the other end being rigid with a sleeve 45 embracing the upper end of an upright rod 46, and adjustably locked thereto against rotation by means of a clamping screw 41. The lower end of this rod 46 fits into a socket 48, and is held therein against rotation by a pin 50 in said rod seated in a V-notch in the upper end of said socket. Socket 48 is connected to an upright bar 52 which is guided for vertical movement along a fixed rod 53, and which is vertically moved from a hoist motor 54 through a. suitable reduction gearing 55, which may include a threaded connection between the lower end of said. bar and a rotatably driven axially fixed embracing sleeve (not shown).

The device is shown in Fig. 2 in its uppermost position with the electrodes I! raised above a mold 10. When it is desired to lower the electrodes l I into the mold H) for hot-topping operations, the motor 54 is operated to lower the bar 52, and in turn the electrode circulating unit l4. Current is supplied to the electrodes I! in any suitable manner, and the metal il in the molds I0 is grounded to maintain the circuits through the current discharge gaps intervening between said electrodes and said metal.

The electrode circulating unit I4 may be adjusted slidably through the cross-head 42 or angularly through the sleeve 45 to position the electrodes l'l directly above any one of the four molds I9 shown.

When the device is not in use, it may be retracted and stored out of the way by sliding the beam 40 to the right through the cross-head 42, lifting the rod 46 out of the socket 48, and supporting the part of the device above said socket on suitable brackets (not shown) in the housing 39.

The circulating liquid 25 may be water as described, or if desired, it may be a liquid having a lower freezing temperature. If additional radiation for the cooling liquid is required during use, this may be provided by passing this liquid through a coil or radiator of some suitable design without materially affecting the compactness self-contained characteristics of the device.

As many changes can be made in the above apparatus, and many apparently widely different embodiments of this invention can be made without departing from the scope of the claims, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. An electrode unit comprising a receiver divided into two compartments, a pump having an outlet connected to one of said compartments and an inlet connected to the other of said compartments, and a non-consumable hollow electrode connected directly to said receiver and having two adjoining flow chambers extending therealong and connected in series, one of said chambers being in communication with one of said compartments, and the other chamber being in communication with the other compartment; said receiver, said pump, and said electrode being united closely to form a compact, self-contained unit.

2. An electrode unit comprising a receiver divided into two adjoining compartments by a partition, a pump having an outlet connected to one of said compartments and an inlet connected to the other of said compartments, and a nonconsumable hollow electrode connected directly to said receiver and containing an open-ended inner pipe passing through one compartment and communicating with the other compartment, said inner pipe defining with the outer wall of said electrode an annular chamber connected in series with the passage in said inner pipe and communicating with said one compartment; said receiver, said pump and said electrode being united closely to form a compact, self-contained unit.

3. A hot-topping rig comprising a receiver divided by a substantially horizontal partition into two superposed compartments, a bed-plate rigid with the wall of said receiver, an electric motor supported on and secured to said bed-plate. a pump connected directly to said motor and operated therefrom, said pump having an outlet connected to the upper compartment and inlet connected to the lower compartment, and a nonconsumable hollow electrode connected directly to the underside of said receiver and containing an open-ended inner pipe passing through the lower compartment and communicating with the upper compartment, said inner pipe defining with the outer wall of said electrode an annular chamber connected in series with the passage in said inner pipe and communicating with the lower compartment; said receiver, said pump and said electrode file of this patent:

UNITED STATES PATENTS being united closely to form a compact, self- Number Name Date contained unit. 1,294,688 Machlet Feb. 18, 1919 ROBERT K. HOPKINS. 5 ,231,33 SOmes Apr. 28, 1942 REFERENCES CITED FOREIGN PATENTS Number Country Date he o l wing references are of record in the 9,200 Great Britain 1887

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