BATCH CHARGE CONVEYING SYSTEMS FOR ELECTRIC INDUCTION FURNACES

Abstract

A batch charge conveying system is provided for multiple electric induction furnaces where each one of the multiple furnaces has a separate charge conveying apparatus. An assembled batch charge is loaded on a single assembled batch charge transport apparatus that selectively delivers the assembled batch charge to a separate charge conveying apparatus associated with one of the multiple electric induction furnaces.

Claims

1. A batch charge conveying system for two or more electric induction furnaces, the batch charge conveying system comprising: a separate charge conveying apparatus for conveying an assembled batch charge to each one of the two or more electric induction furnaces, the separate charge conveying apparatus having a conveying charge load end and a furnace charge load end; and a single assembled batch charge transport apparatus for receiving a selected charge materials forming the assembled batch charge on the single assembled batch charge transport apparatus, the single assembled batch charge transport apparatus having an assembled batch charge transport driver system arranged to move the single assembled batch charge transport apparatus with the assembled batch charge to a conveyor charge loading station adjacent to the conveying charge load end of one of the separate charge conveying apparatus for transfer of the assembled batch charge to the one of the separate charge conveying apparatus.

2. The batch charge conveying system for two or more electric induction furnaces of claim 1 further comprising a single batch charge loading station for the single assembled batch charge transport apparatus to receive the selected charge materials, the assembled batch charge transport driver system arranged to move the single assembled batch charge transport apparatus between the single batch charge loading station and the conveyor charge loading station for each of the separate charge conveying apparatus.

3. The batch charge conveying system for two or more electric induction furnaces of claim 1 further comprising a batch charge loading station for the single assembled batch charge transport apparatus collocated with the conveyor charge loading station for at least one of the separate conveying apparatus.

4. The batch charge conveying system for two or more electric induction furnaces of claim 1 further comprising a means for moving of the separate conveying apparatus between a conveyor charge loading position for the transfer of the assembled batch charge from the single assembled batch charge transport apparatus to the separate conveying apparatus and a conveyor furnace charge loading position for the transfer of the assembled batch charge from the separate conveying apparatus.

5. A method of conveying an assembled batch furnace charge to one of a separate charge conveying apparatus for each one of a plurality of electric induction furnaces, the method comprising sequentially performing the following steps: (a) loading an assembled batch charge onto a single assembled batch charge transport apparatus at a batch charge loading station; (b) moving the single assembled batch charge transport apparatus with the assembled batch charge to a selected one of a separate batch charge loading station associated with each of the separate charge conveying apparatus; (c) transferring the assembled batch charge on the single assembled batch charge transport apparatus input position to the separate charge conveying apparatus at the selected one of the separate batch charge loading station to form an unloaded single assembled batch charge transport apparatus; and (d) moving the unloaded single assembled batch charge transport apparatus to the batch charge loading station and sequentially repeating steps (a) through (c) at the remaining separate batch charge loading stations associated with each of the remaining separate charge conveying apparatus to optimize process time when repeatedly melting, melt heating, and melt drawing in each of the plurality of electric induction furnaces with charging each of the plurality of electric induction furnaces with a single assembled batch charge transport apparatus.

6. The method of claim 5 wherein the step of loading the selected assembled batch charge is performed at one of the separate batch charge loading stations.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The appended drawings, as briefly summarized below, are provided for exemplary understanding of the invention, and do not limit the invention as further set forth in this specification and the appended claims.

[0012] FIG. 1(a) and FIG. 1(b) diagrammatically illustrate one example of an in-line batch charge conveying system where a single stationary batch charge assembly station serves a single electric induction furnace via a charge conveying apparatus.

[0013] FIG. 2 diagrammatically illustrates one example of a single stationary batch charge assembly apparatus selectively servicing one of two electric induction furnaces via a switchable conveying system supplying an assembled batch charge selectively to one of the two furnaces by switching of the conveying path leading to one of the two furnaces.

[0014] FIG. 3 diagrammatically illustrates another example of a batch charge conveying system supplying an assembled batch charge to each one of two induction furnaces where each of the two induction furnaces has a dedicated batch charge assembly station.

[0015] FIG. 4(a) through FIG. 4(e) diagrammatically illustrate one example of a batch charge conveying system of the present invention where a single assembled batch charge transfer apparatus selectively supplies an assembled batch charge to any one of two induction furnaces.

[0016] FIG. 5(a) and FIG. 5(b) diagrammatically illustrate another example of a batch charge conveying system of the present invention where a single assembled batch charge transfer apparatus selectively supplies an assembled batch charge to any one of two induction furnaces.

DETAILED DESCRIPTION OF THE INVENTION

[0017] FIG. 4(a) through FIG. 4(e) illustrate one example of a batch charge conveying system 40 of the present invention for two or more electric induction furnaces. Although the embodiment of the invention in the figures is for two electric induction furnaces, other embodiments of the invention comprise batch charge conveying systems for more than two furnaces where the object is to optimize process time with repeated process cycles of: delivering an assembled batch charge to each furnace; melting the charge and melt heating in each furnace;

[0018] and drawing the melt from each furnace where the batch charge conveying system utilizes a single assembled batch charge transport apparatus for delivering the assembled batch charge to each furnace.

[0019] In FIG. 4(a) a single assembled batch charge transport apparatus 20 is positioned between two charge conveying apparatus 14a and 14b. Charge conveying apparatus 14a is adjacent to batch charge loading station a with conveying apparatus 14a provided to supply an assembled batch charge to electric induction furnace 16a and with charge conveying apparatus 14b provided to supply an assembled batch charge to electric induction furnace 16b. In this embodiment of the invention a single batch charge loading station a for assembled batch charge transport apparatus 20 is located separate from conveying apparatus batch charge loading stations b and c for conveying apparatus 14a and 14b respectively. Selected charge materials are delivered to batch charge loading station a by a suitable material handling and transfer apparatus, for example, a charge material conveyor upon which measured portions of different charge materials are deposited at different charge material storage stations and transferred to assembled batch charge transport apparatus 20 at loading station a to form an assembled batch charge on the assembled batch charge transport apparatus.

[0020] In FIG. 4(a) both conveying apparatus 14a and 14b are shown in the retracted position (withdrawn from furnaces 16a and 16b respectively) with their right ends (14a and 14b) adjacent to conveyor charge loading stations b and c respectively where the assembled batch charge on assembled batch charge transport 20 can be selectively transferred to the right end of either conveyor apparatus 14a or 14b when the assembled batch charge transport is moved from charge loading station a to either conveyor charge loading station b or c respectively.

[0021] After the assembled batch charge load is transferred and loaded on assembled batch charge transport station 20 in FIG. 4(a), assembled batch charge transport apparatus 20 selectively moves to conveyor charge loading station b in FIG. 4(b) and the assembled batch charge on the assembled batch charge transport station 20 is transferred to charge conveying apparatus 14a, which is in the conveyor charge load position at loading station b, while in FIG. 4(b) a previously assembled batch charge on the assembled batch charge transport 20 has been transferred to conveyor apparatus 14b and the conveyor apparatus 14b has moved to the furnace charge load position to load antoher previously assembled batch charge into the crucible of furnace 16b.

[0022] Transfer of the assembled batch charge on assembled batch charge transport apparatus 20 to conveying apparatus 14a or 14b can be accomplished by a transfer means such as a power driven belt or a vibratory transfer table on the assembled batch charge transport apparatus or a power driven hinged open-box bed on the transport apparatus that dumps the assembled batch charge onto the selected charge conveying apparatus.

[0023] After a previously assembled batch charge has been melted, heated to a required melt temperature and drawn from furnace 16a, conveying apparatus 14a with the assembled batch charge loaded in FIG. 4(b) moves from the retracted conveyor position to the furnace charge load position for loading of the assembled batch charge into the crucible of furnace 16a as show in FIG. 4(c) while charge conveyor apparatus 14b moves from the furnace charge load position in

[0024] FIG. 4(b) to the retracted conveyor position adjacent to conveyor charge load station c as shown in FIG. 4(c) and empty (unloaded) assembled batch charge transport apparatus 20 moves to batch charge loading station a as shown in FIG. 4(c).

[0025] After the assembled batch charge load is transferred and loaded on assembled batch charge transport apparatus 20 in FIG. 4(c), assembled batch charge assembly station 20 selectively moves to conveyor charge loading station c in FIG. 4(d) and the assembled batch charge on the assembled batch charge transport station 20 is transferred to charge conveying apparatus 14b, which is in the conveyor charge load position at station c as shown in FIG. 4(d).

[0026] In FIG. 4(e) after the previously assembled batch charge has been melted, heated to a required melt temperature and drawn from furnace 16b in FIG. 4(d), conveying apparatus 14b with the assembled batch charge loaded in FIG. 4(d) moves from the retracted conveyor position to the furnace charge load position to load the assembled batch charge load into the crucible of furnace 16b as show in FIG. 4(e) to begin a new batch melt while conveyor apparatus 14a moves from the furnace charge load position to the retracted conveyor position adjacent to load station c and empty (unloaded) assembled batch charge transport apparatus 20 moves to batch charge loading station a.

[0027] In one embodiment of the invention the apparatus and process described in FIG. 4(a) to FIG. 4(e) can be sequentially repeated after the apparatus and process shown in FIG. 4(e) by returning to the apparatus and process described sequentially from FIG. 4(b) through FIG. 4(e). With the batch charge conveying system of the present invention a single assembled batch charge transport apparatus 20 is used to optimize process time and efficiency by transferring an assembled batch charge to a charge conveyor apparatus associated with a furnace that is completing the melting and drawing process cycles while other furnaces in the system are beginning or are in the melting and drawing process cycles.

[0028] Movement and repositioning of the single assembled batch charge transport apparatus 20 in all embodiments of the invention, for example, between loading stations a, b and c in

[0029] FIG. 4(a) through FIG. 4(e), can be accomplished by an assembled batch charge transport driver, for example, a wheelset (wheel-axle assembly) attached to the single assembled batch charge transport apparatus where the wheels move over rails installed at ground level or in structure associated with supporting material handling equipment.

[0030] Summarizing one embodiment of the invention, the batch charge conveying system for two or more electric induction furnaces has a separate charge conveying apparatus for conveying an assembled batch charge to each one of the two or more electric induction furnaces with the separate charge conveying apparatus having an assembled batch charge receiving end and an assembled batch charge furnace delivery end. A single assembled batch charge transport apparatus receives selected charge materials forming the assembled batch charge on the single assembled batch charge transport apparatus. The single assembled batch charge transport apparatus has an assembled batch charge transport driver arranged to move the single assembled batch charge transport apparatus with the assembled batch charge to a separate conveying apparatus batch charge load station adjacent to the assembled batch charge receiving end of a selected one of the separate charge conveying apparatus for transfer of the assembled batch charge to the selected one of the separate charge conveying apparatus.

[0031] In all embodiments of the invention selection of the order in supplying the assembled batch charge to a furnace's charge conveying apparatus can be made by a furnace control system based upon where in the process cycle of loading charge; melting charge; melt heating and drawing each furnace in a particular multiple furnace system; a furnace in a multiple furnace that is finishing the drawing of the melt from the furnace generally has the highest priority for delivery of an assembled batch charge for the next batch process of induction melting, heating and drawing of melt from the furnace as known in the art.

[0032] FIG. 5(a) and FIG. 5(b) illustrate another embodiment of the invention where the single batch load charge loading station a in FIG. 4(a) through FIG. 4(e) is integrated into at least one of the charge conveying apparatus batch loading stations b and c as illustrated by reference sign (b+a) in FIG. 5(a) and FIG. 5(b) so that as shown in FIG. 5(a) assembled batch charge transport apparatus 20 can be loaded with an assembled batch charge at loading station (b+a) and then selectively transfer the assembled batch charge to charge conveying apparatus 14a for delivery to electric induction furnace 16a at the same loading station (b+a) or move to loading station c and transfer the assembled batch charge to conveying apparatus 14b for delivery to electric induction furnace 16b.

[0033] The process of the present invention can also be used in an arrangement of three or more induction furnaces where the single assembled batch charge transport apparatus moves among multiple charge conveying apparatus dedicated to each of the three or more induction furnaces to deliver an assembled batch charge to a selected one of the multiple charge conveying apparatus while the furnaces associated with the other multiple charge conveying apparatus perform process steps associated with inductively heating, melting and/or drawing molten material from the furnaces.

[0034] In another embodiment of the invention a method of conveying a selected assembled batch furnace charge from a single assembled batch charge transport apparatus to a selected one of a separate charge conveying apparatus for each one of a plurality of electric induction furnaces is provided. In this embodiment the method the sequentially performed steps include:

[0035] (a) positioning the single assembled batch charge transport apparatus adjacent to a batch charge receiving end of the selected one of the separate charge conveying apparatus;

[0036] (b) transferring the selected assembled batch furnace charge on the single assembled batch charge transport apparatus to the batch charge receiving end of the selected one of the separate charge conveying apparatus;

[0037] (c) processing an inputted change in the selected assembled batch furnace charge and an inputted change in the selected one of the separate charge conveying apparatus in a furnace batch conveyor control system;

[0038] (d) loading the selected assembled batch furnace charge processed in step (c) on the single assembled batch charge transport apparatus;

[0039] (e) positioning the single assembled batch charge transport apparatus to an assembled batch charge delivery station adjacent to the batch charge receiving end of the selected one of the separate charge conveying apparatus processed in step (c);

[0040] (f) transferring the selected assembled batch furnace charge processed in step (c) on the single assembled batch charge transport apparatus to the batch charge receiving end of the selected one of the separate charge conveying apparatus processed in step (c); and

[0041] (g) sequentially repeating steps (c) through (f) to convey the selected assembled batch furnace charge from a single assembled batch charge transport apparatus to the selected one of the separate charge conveying apparatus for each one of a plurality of electric induction furnaces.

[0042] In the description above, for the purposes of explanation, numerous specific requirements and several specific details have been set forth in order to provide a thorough understanding of the example and embodiments. It will be apparent however, to one skilled in the art, that one or more other examples or embodiments may be practiced without some of these specific details. The particular embodiments described are not provided to limit the invention but to illustrate it.

[0043] Reference throughout this specification to one example or embodiment, an example or embodiment, one or more examples or embodiments, or different example or embodiments, for example, means that a particular feature may be included in the practice of the invention. In the description various features are sometimes grouped together in a single example, embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of various inventive aspects.

[0044] The present invention has been described in terms of preferred examples and embodiments. Equivalents, alternatives and modifications, aside from those expressly stated, are possible and within the scope of the invention.