JPS5989979A - Furnace device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The invention comprises a first vessel having a first chamber intended for the melt and at least one inductor unit connected to this first chamber; The inductor unit includes a block made of ceramic material and a magnetic core for a closed magnetic circuit, formed with at least two legs and at least two yokes, surrounding the magnetic core. Also comprising a primary winding, said block is formed with a through hole surrounding one of said legs, and said block has a surface for defining a roof 0 which acts as a secondary winding formed by said melt. The present invention relates to a furnace device comprising the following.

A device of the above-mentioned class Illi is known, inter alia, from the specification of Japanese Patent No. 777.547.

In such equipment, the metal present in the furnace chamber - usually aluminum or aluminium - is normally removed for long periods of time, for example several hours or hundreds of hours, when melting and melt feeding are not taking place. It is desirable to maintain the contained alloy in a molten state.

However, the use of inductors for such heat retention of the melt is hampered by the high ambient temperatures, so the primary winding of an inductor of the above type is usually driven through cooling channels. It is quite uneconomical since it requires extremely powerful cooling with the aid of a coolant. The problem sought to be solved by the present invention is to reduce the power required for heat retention while maintaining the inductor, which is highly advantageous for melting purposes, without significant additional expense. It is an object of the present invention to provide a furnace device in which the This is achieved by using a heat source specifically designed for heat retention.

The furnace apparatus according to the invention is characterized in that the apparatus also includes a second container having a second chamber, and the blocks are positioned adjacent to each other and extend to one side in each of the holes. and two mutually opposed confining surfaces and two channels for molten metal, each of said channels extending between and opening at said confining surfaces, said block characterized in that it is mounted between said first and second containers, with each of said limiting surfaces in contact with one of said containers.

Conventional furnace inductors include a cover of metallic material, and connection of the inductor to the furnace vessel is made by seven-lunging the shell to the vessel. According to a further development of the invention, the inductor described above does not have a shell of this kind, thus eliminating eddy current losses that would otherwise occur.

According to a further development of the invention, said ceramic body is made of a material that withstands relatively high compressive stresses, such that the inductor is fixed by installing stones between the two furnace vessels. It is made as a self-supporting stone.

Mounting and unloading can therefore be carried out very quickly, which means that furnace inductors for channel induction furnaces generally have to be replaced at relatively short time intervals, for example annually. This is advantageous because it does not.

The term "contraction distance" generally refers to the length of the channel in the inductor along which a solidified metal object forms when the furnace is powered down. On further cooling, this object will shrink, since its contraction is to some extent prevented by the channels mentioned above.
Easily cracks. As a result of this crack formation, the inductor's secondary circuit is often broken. The inductor according to the invention also has a shorter contraction distance compared to prior art inductors, as evidenced by the fact that the channels of this inductor open towards the two furnace chambers. It has the advantage of being This contraction distance has thus been reduced by approximately 1/3 compared to prior art inductors.

In a first preferred embodiment of the invention, the first
and/or the second chamber also includes a heat source arranged above the melt, which heat source can be activated when the inductor is switched off and whose maximum power is Although less than the maximum power of the inductor, it is sufficient to maintain the molten metal in a liquid state for at least 24 hours. In this way, it is possible to avoid solidification of the molten metal present in the inductor channel with a relatively low heat retention power of the heat source.

In still another preferred example of the present invention, the above-mentioned 2
The number of channels between the two furnace chambers is at least 4 and preferably at least 6, divided into 2 or 6 pairs, each one of which is connected to one phase included in a two-phase or polyphase system. The primary coils 13', 13''t, supplied by
It surrounds 13m. Thus, in this case the device according to the invention has been expanded to make it possible to be supplied with a two-phase or a six-phase' commercial flow. This means that the capabilities of the device are significantly improved and efficiency is concerned. It was possible to achieve efficiency increases of 10% or more. In the case of low power operation, it is also possible to shut off one of the phases and still achieve a heat retention effect; this comes at the expense of the reactive loading of this network, but this can be recovered by using a compensator.

These inductor blocks can be configured into one modular system in order to obtain a melting device with the melting capacity of each wing and while using only one size of the inductor blocks.

In the following, the invention will be explained in more detail with reference to the accompanying drawings, in which: FIG.

The figures 1 to 4 show two furnace vessels 1 and 1.
A furnace arrangement consisting of ' is shown. The furnace vessels 1 and 1' are identical to each other, but whereas the furnace vessel 1 is provided with an outlet opening 2 for the molten metal, the corresponding opening of the furnace vessel 1' is sealed or excluded. They are different from each other in that they are Each of the furnace vessels 1 and 1' has a vessel 3 and 3' made of sheet metal with a lining 4 and 4' of ceramic material, respectively, and includes a furnace chamber 5 and 5', respectively. Furnace induction 16 is connected to two furnace vessels 1 and 1'
are arranged between. The furnace inductor 6 includes an inductor block 7 made in the form of one single stone made of ceramic material. In effect, the inductor block γ
is made as a parallelepiped block provided with through holes 8, 9 and 15. 2 in these holes
8 and 9 are horizontally extending, substantially linear, mutually parallel inductor channels. Each of the inductor channels 8 and 9 has a hydraulic connection made through two openings 10 and 10' provided in the two furnace vessels 1 and 1', respectively, to the two furnace chambers 5 and 5'. form between.

The through hole 15 has a substantially circular cylinder with a vertical cylindrical axis 15' and is arranged between the two horizontal inductor channels 8 and 9 and has a leg 11 belonging to the transformer core 12. together with the primary winding 13 surrounding the section. The inductor block 7 has a layer 14 of thermally insulating material, for example ceramic felt, so as to reduce the loss of heat from the inductor to the surrounding air. The inductor blocks I rest on section beams 16 each positioned outside the reactor vessel;
It is fixed in position by a pair of upper tension rods 17 and a pair of lower tension rods 18. The elongated rods 17 and 18 are inserted at their respective ends into lugs 19 which are attached to the furnace chambers 5 and 5' and have nuts 20. The nuts 20 are tensioned and the contact surfaces of the inductor block 7 are thus forced into the furnace chambers 5 and 5 with such force that a pressure-tight connection is obtained between the openings 10° 10' and the inductor channels 8 and 9, respectively. ′ is pressed against the corresponding surface.

Since the inductor 6 is arranged and fixed as described above, its mounting and unloading can be carried out with considerable savings in labor and time. For example, when removing the inductor, the four nuts 20 are loosened more or less easily, so that the inductor can be removed by a horizontal movement or lifted straight up.

Each one of the two furnace vessels 1 and 1' has a cover 22 and 22', respectively, in the form of a box made of sheet metal with a lining of heat-resistant, heat-insulating material. Each cover is provided with a heat source in the form of an electrical resistor 23 and 23' respectively, and said electrical resistor is connected to an alternating current network (not shown) via a corresponding circuit breaker and this inductor is connected to an alternating current network (not shown). It can be switched on and off regardless of whether it is supplied with current or not.

One of each of the two heating elements 23 and 23' is capable of applying less than 15% of the maximum force of the inductor 6, preferably less than 5% thereof, to iJ.
It has the greatest power to The force jointly provided by the two heating elements 23 and 23' is sufficient to keep the melt in a liquid state for several hours, preferably several days, when the inductor is switched off. be. The maximum force of inductor 6 is sufficient for this inductor alone to provide the necessary dissolution efficiency, but this force is also
It can be further increased by using at least one of the thermal elements 23 and 23'.

During normal operation, the surface level of the molten metal is reduced so that the molten metal present in the two furnace chambers 5 and 5', in the two openings 10 and 10' and in the two inductor channels 8 and 9 The quantities cooperate with each other to form a secondary circuit surrounding the transformer leg 11.

When the cover 22' is in the position shown in phantom in FIG. 2, the material to be melted, e.g. aluminum,
Charging takes place by feeding magnesium or an alloy containing these metals or certain of them into the furnace chamber 5'.

If the melt reaches the outlet opening 2, further charging will result in the molten metal flowing out from the opening 2. 1st
The furnace arrangement illustrated in FIGS. 4 to 4 is based on special heat-holding furnaces (known per se) in which the volume of the furnace chamber is at least twice and preferably at least five times larger than the volume of the furnace chamber 5. Therefore, it can be suitably used in conjunction with the device (not shown in FIG. 5).

Thus, the outlet opening 2 is suitably provided with an outlet, -Ix
The molten metal flowing out through the inlet and outlet is supplied to the special heat holding furnace.

In cases where a special heat-holding furnace already exists,
It is advantageous to use two practically identical furnace vessels as in the furnace arrangement described above. This is because this is advantageous from a manufacturing point of view.

In other cases, the apparatus shown in FIGS. 1 to 4 differs only in that the furnace vessel 1 is replaced by a furnace vessel 25 which differs in size and design. It is advantageous to use instead the device shown in FIG. 5, which is different. The furnace vessel 25 has a thermally insulating cover 26 on the underside of which heating elements 21 in the form of electrical resistors are arranged. The furnace volume 8a25 consists of a furnace chamber 2B defined by a cover 25 in the upper direction. A vertical partition wall 30' divides the furnace chamber 28 into two compartments 29 and 30 which are arranged adjacent to each other and communicate with each other. Ward lI! The only way for the melt in II 29 to flow into compartment 30 is through an overflow wedge 32 located in partition 30'. The furnace chamber 5' is charged with aluminum in solid state. This figure shows the situation in which the entire amount of charged aluminum has been melted and only furnace chambers 5 and 28 contain molten metal. This means that the surface level 34 in the compartment 29 is
It is a pity that it is on the same plane as the inner surface level 35. As charging continues, the molten metal flows over the overflow wedge 32 and flows through the overflow wedge 32. 1130, thus raising the superficial level 33 of the melt present in this compartment. Compartment 30 contains at least twice as much liquid metal as compartment 29, and preferably at least 6 times more. The compartment 29 communicates with the inductor channel of the inductor 6 through an opening 31 provided in the wall of the furnace vessel 25 . The vertical distance between the overflow edge 32 and the cover 26 should be less than 40% of the average texture of the oven chamber 28.

The inductor 6 is cooled with air by a blower driven by a blower motor 37.

The embodiments of the invention described with reference to the accompanying drawings constitute only two of the many possible embodiments of the invention.

Thus, for example, the air heating grate 23, 23' and 27 can be replaced by a different persimmon heat source, for example a gas burner.

Although FIG. 6 shows inductors for a six-phase supply - one inductor per phase, the concept can also be applied to a two-phase supply. In FIG. 1, two furnace vessels or chambers 1 and 1' are shown and are identical to each other. (The furnace vessel 1 has a venting device (not shown) similar to known devices.) FIG. 1 shows a furnace vessel enclosed within a shell 3 of thin sheet steel, with reference numerals 10 and 10' indicating the long openings into these chambers.

FIG. 4 (and FIG. 1) shows an inductor 6 arranged between said furnace chambers and comprising an inductor block 1 made in the form of a stone of ceramic material. Two channels 8 and 9 interconnect the chambers and are included in the secondary circuit of the channel furnace inductor. Its second coil is designated by the symbol 13. Reference numeral 12 indicates an iron core, and reference numeral 11 indicates a leg.

The device according to FIG. 3 is identical to the device described above, and the inductor is made as a parallelepiped block. The inductor has a layer 14 of thermally insulating material and has through holes 15 for the primary coil and core.

The inductor 6 is fastened to the chamber 1 by tension rods 1B, 17 (see FIG. 5). That is, the rod is inserted at each end into a lug 19 which is tightened into the chamber 1 and is provided with a lug 20. Said nut is screwed tightly, thus contacting surface 21 of said inductor block
is pressed against the corresponding surface 21 of said chamber.

Said covers, each with a resistive heating element, are not shown but are evident from the patent application document #ilI.

According to the invention, the device has two or six inductors 6 (in the case of six phases), each inductor having a chamber 1 (FIG. 6).
It has two channels 38, 39, 40 and 41, 42, 43 respectively extending between them. These terminals thus connect the primary coils 13', 13', respectively.
Included within the secondary circuit of the six channel Nohi furnace inductors with 13'' coils 13', 13',
13"' are arranged on the iron core (Fig. 7), each of which is connected to the sixth
It is positioned as shown in the figure.

The six (or two) inductor locks 6 are identical to each other and are tightened by tension rods 17, 18 and tension bolts 44.

These bricks are fastened by four tension bolts and arranged with layers of ceramic felt between them. Inductor channel 3B- between said two chambers
43 is also illustrated in FIG. These six blocks 6, which are connected to each other, are positioned together with the transformer core 12 and the coil 13 on one stand.

The charging section and overflow section 1' and 1 are each fastened by a bolt 44 located on one side of each inductor block. A butt stitch for the container (chamber) is also illustrated in FIG.

It is also possible to use two or more inductor blocks for each phase.

FIG. 10 shows an inductor block forming a modular system, for example, forming a melting furnace for aluminum, thus obtaining a melting device with various melting capacities;
Moreover, it shows the possibility of using one single size inductor block 45.

These blocks 45 are located adjacent to each other and/or in a row between the two containers 1, 1'.
i can be determined. FIG. 10 shows an example of different power selections, namely 130KW.

Showing 260 KW, 90 KW, 1520 KWl and 780 KW.

The device according to the above can be modified in various ways within the scope of the claims.

[Brief explanation of drawings]

Fig. 1 is a view from above of a first practical example of the furnace equipment according to the present invention, and Fig. 2 is a view perpendicular to the vertical plane passing through the line u-n in Fig. 1. Elevation view of the same equipment, Figure 6 is a horizontal cross-sectional view along line m and m in Figure 2, Figure 4 is a horizontal sectional view along line 1
Fig. 5 is a vertical cross-sectional side view of the second working material of the present invention; Fig. 6 is a polyphase Figure 7 shows the inductor for magnetic feeding, Figure 7 shows the installation of the primary coil in the case of multi-phase, and Figure 8 shows the inductor 1! in the case of multi-phase. FIG. 9 is a view similar to FIG. 8 except when viewed from the side; FIG. 10 is a view showing a module system according to the invention. 1.1'...Furnace vessel, 2...Outlet opening, 3,3'
...Container, 4.4'...Lining, 5.5'...
・Furnace chamber, 6...furnace inductor, 7...inductor block,
8,9.15... Through hole, 10, 10'... Opening, 11... Leg, 12... Transformer magnetic core, 13...
- secondary winding, 14... layer of thermally insulating material, 15... vertical cylinder axis, 16... section beam, 17.
18... tension rondo, 19... lug, 20...
Nut, 21...Contact surface, 22, 22'...Cover, 23, 23'...'1 section air resistor, 25...
-Furnace vessel, 26...thermal insulation cover, 28...furnace chamber,
29.30...Division, 30'...Vertical partition wall, 3
2... Overflow wedge, 33.34... Surface level, 36... Exit opening, 37... Blower motor, 38.39; 40.41; 42.43... Channel, 44... ·bolt. F/6.2 r-tυ l FIG, 4 FIG5 F/(3,6 R FIG, 7 38- FIG, 70

Claims (1)

Claims: (1) a first chamber (5) intended for the melt and at least one inductor unit (
6), said inductor unit (6) comprising a block (7) made of ceramic material, at least two legs and at least two meeters; Magnetic core (12) for a closed magnetic circuit formed
A primary volume containing and surrounding this magnetic core, 1il
J (13), said block (7) is formed with a through hole (15) surrounding one of said legs, said block (7) as a secondary winding formed by said melt. A furnace apparatus comprising a surface for defining a working loop, said furnace apparatus also comprising a second container (1') having a second chamber (5'), and said block (7) are positioned adjacent to each other such that said holes (
15), two mutually opposed confining surfaces (21) and two channels (8) for the molten metal extending to one side in each case.
, 9), each of said channels extending between and opening in said limiting surfaces (21), said block (7) extending each of said limiting surfaces (21) into one of said containers. A furnace apparatus characterized in that it is installed between the first container (1) and the second container (1') in contact with each other. (2. In the furnace apparatus according to claim 1, the first chamber (5) and/or the second chamber (5') also include a heat source (23') arranged above the molten metal. (3) In the furnace apparatus according to claim 1, L
Furnace device, characterized in that the heat source is an electrical resistor (23') supported by a cover (22) and configured as a heating element. (4) A furnace system according to claim 1, characterized in that the two furnace chambers are hydraulically connected to each other by the inductor channels (8, 9). (5) In the furnace apparatus according to claim 4, the first (5) and second (5') furnace chambers are the first (1) and second (1') furnace vessels, respectively. Each of said two furnace vessels has a furnace opening (10, 10M) provided in the side wall, so that two furnace chambers (5, 5') are provided in said inductor. said first (5) and said second (5') furnace chambers are arranged on one side of each of said furnace openings (10, 10') and said inductor channels (8, 9).
) A furnace apparatus characterized in that it is hydraulically interconnected by. (6) In the furnace apparatus according to claim 5, the first (1) and the second (1') furnace vessels extend between the two furnace vessels to transmit tensile force. A furnace apparatus characterized in that the inductor (6) is pressed against one side of each inductor (6) by a plurality of members (17, 18). (7) In the furnace apparatus according to claim 5, the inductor channel (8,
9) A furnace apparatus characterized in that it is substantially symmetrical with respect to a virtual vertical plane (■-■) laterally intersecting the plane. (8) In the furnace apparatus according to claim 5, at least one of the furnace vessels (1, 1') is provided on a clay wall portion and is hydraulically connected to an upper portion of the furnace chamber. The furnace apparatus is further characterized in that it has a tapping device (2) for molten metal. (9) In the furnace apparatus according to claim 1, the second furnace chamber (5') is provided with a vertical partition (30'),
a subsection (2) directly connected to said inductor channel;
9), and a large section (30) having an outlet opening (36) for molten metal near the bottom of the furnace chamber, and a large section (30) having an outlet opening (36) for the molten metal near the bottom of the second furnace chamber, and A partition (30') or an overflow wedge (32) is provided over which the molten metal flows from said small compartment (29) to said large compartment (30), said inductor Furnace apparatus, characterized in that the supply of molten metal from the channel to the large section takes place only by flowing over the overflow wedge (32) and through the small section (29). α0) In the furnace apparatus according to claim 1, the number of channels between the two furnace chambers is at least 4.
books, preferably at least 6, with 2 said channels.
or a primary winding divided into six pairs, each pair fed by one phase included in a two-phase or polyphase system (
13', 13', 13'') and its magnetic core. (11) The furnace apparatus according to claim 10, in which the separate inductors A furnace device characterized in that the chambers (44) are connected to each other by chambers (44). (b) In the furnace device according to any one of claims 1 to 11, 1) No.1
(18) In the furnace apparatus according to any one of claims 1 to 12, the inductor block is provided with an opening device. Furnace device, characterized in that it is provided in standard dimensions and is intended to be integrated into a modular system in order to obtain melting devices with various melting capacities. a→ In the furnace device a according to claim 2,
The heat source (23') can be activated even after the inductor has been switched off, and its maximum power is less than the maximum power of the inductor (6), but at least A furnace device characterized in that it is sufficient to remain in a liquid state for 24 hours. (15) In the furnace apparatus according to claim 1, the volume of the second furnace chamber (5') is smaller than that of the first furnace chamber (5').
5) A furnace device characterized in that the volume is at least twice as large as the volume of item 5).