RU2601041C2 - Electric melting furnace - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: invention can be used for maintenance of an electric melting furnace. Furnace consists of fixed bearing frame and supported on frame in working position melting vessel, a cart for changing vessel,to be displaced between parking position (P) parking and transfer position (Ü), having a retainer for melting reservoir, disconnecting melting reservoir in transfer position from bearing frame and mounted in retainer of cart for changing vessel transfer device, wherein by means of transfer device bearing frame can be dropped relative to transfer position (Ü) for changing from operating position (A) so that during lowering melting vessel first, is installed on retainer, and then being raised from bearing frame is detached from it, bearing frame is equipped with props to complete tilting.

EFFECT: invention makes it possible to install lifting or tilting mechanism fixed at shaft and support melting vessel on a stationary holder, wherein cart for replacement of reservoir is used only for intended purpose.

21 cl, 5 dwg

Description

The invention relates to an electric melting furnace, which includes a stationary mounted support frame and a melting tank resting on the supporting frame in the working position, including a trolley for changing the tank, moved between the parking position and the transfer position, having a latch for the melting tank.

An electric arc furnace (EAF) is used as a large installation, in particular, for industrial melting of steel scrap, in order to regenerate steel during the recovery process. Such an electric smelting furnace has a melting tank in which steel scrap is melted or, accordingly, pyrometallurgically processed. A melting tank is, for example, a so-called lower tank having a classically laid lining, which must be regularly serviced or repaired. The smelting vessel may, however, contain, along with the lower vessel, the upper vessel, for example, side water-cooled panel walls and burner panels, which must also be serviced. Therefore, with the so-called replacement tank technology, it is required to remove the melting tank, for example, at regular intervals for maintenance or, in an emergency, from the vicinity of the furnace itself. In all cases, the melting tank must thus be moved or, accordingly, removed from its working position, in which the melting process takes place.

Electric melting furnaces, in particular, are made in the form of shaft furnaces with a permanently installed upper tank or shaft. The mine serves to load the melting tank and, for example, also pre-heat the mixture intended for melting. Access to the melting tank by means of the workshop crane is then absent, since the melting tank in its working position is blocked by the fixedly installed furnace elements.

Therefore, from EP 0 385 434 B1, a so-called trolley for a shaft furnace tank is known. A known tank trolley includes a melting tank, covering the melting tank frame part, which can walk personnel, and a mechanism for moving and tipping, including its own hydraulic installation. All components move simultaneously on the trolley for the container or, accordingly, form a movable unit. The hydraulic unit is used to lower the melting tank from the mine above it, as well as tipping the melting tank to drain the slag or to release the steel melt.

To remove the melting vessel from the vicinity of the furnace, the melting vessel is lowered from the shaft located above it or, accordingly, the upper vessel, and then the entire truck for the vessel from the working position is moved to the parking position. There, the tank trolley can be serviced or, for example, the melting tank can be lifted using a workshop crane. The parking position is also the position of the extraction of the melting capacity. The trolley for the tank is constantly supported on wheels and rails, that is, it has its own rail track. Wheels and rails during the melting process are constantly loaded with technological fluctuations, as well as the high dead weight of the trolley for a tank with a filled melting tank and a hydraulic installation. In order to ensure technological reliability, in addition, the lifting and tipping hydraulics are made redundantly, so that, in particular, the overturned melting tank, even if the lifting cylinder fails, can again move back to the horizontal initial position by means of the redundant lifting cylinder.

The known electric melting furnace has a different, narrower rail track for a bucket carriage moving along it, which has its own movement drive. The bucket trolley carries a casting bucket for placing molten steel. The bucket trolley must be able to move, starting from the electric furnace, through the parking position of the trolley for the tank beyond, so that the trolley for the tank can move to this place. Therefore, the rail track of the bucket trolley must extend beyond the parking position.

In well-known electric smelting furnaces, both trolley for containers and bucket trolleys can be removed from the vicinity of the furnace in only one single direction. In other words, both rail tracks end at the electric furnace.

DE 429 667 C2 describes a steelmaking plant comprising a metallurgical vessel fixed to an annular support member and devices for feeding a charge and discharging liquid molten material. The upper part of the tank and the lower part of the tank located under the annular bearing element are fixed to the bearing element with the possibility of detachment and replacement.

An object of the present invention is to provide an improved electric melting furnace.

The problem is solved by means of an electric melting furnace according to claim 1 of the claims. The furnace has a permanently installed supporting frame. In the working position of the melting tank, the melting tank rests on a supporting frame or, accordingly, is mounted on it. An electric melting furnace also includes a trolley for changing containers. The trolley for changing the capacity has a lock for the melting capacity and can be moved between the parking position and the transfer position. An electric melting furnace also includes a transfer device for transferring the melting vessel to a trolley for changing the vessel. The transfer device is designed so that when the trolley for changing the capacity is in the transfer position, disconnect the melting capacity from the carrier frame and install or, accordingly, fix it in the latch of the capacity trolley.

In the operating position, the melting tank, therefore, rests on only one supporting frame, which is installed stationary, for example, on the foundation. The trolley itself for changing the capacity is not loaded. Therefore, the supporting frame can be made accordingly massive, without the need to optimize its weight according to the load on the wheels or rails. The aforementioned lack of constant load on rails and wheels is thus prevented.

The stationary carrier frame also preferably has, as a rule, a hydraulic tipping device, which is necessary for tipping the melting tank, in particular for releasing molten steel or for draining slag. This hydraulics also does not have to be installed on the trolley anymore, but can be more simply installed on a carrier frame in a simpler way and thus leads to no load on the rails. The supporting frame has, for example, for example, a base which is actually stationary mounted on the foundation and hydraulically actuated and thus movable. However, this holder, in contrast to the cart on wheels, is also considered to be installed permanently here. Then the melting tank is mounted on a movable holder.

As a rule, in the electric melting furnace according to the invention, the melting tank in the working position interacts with the stationary shaft of the furnace located above it. For example, gas-tight contact between the stationary shaft of the furnace and the melting tank can be carried out by lowering the melting tank together with the supporting frame or, accordingly, the holder. In other words, the carrier frame then also has a lifting mechanism. Here also take place. advantages of stationary frame support. As a rule, there is thus a combined lifting / tipping mechanism.

The invention is based on the idea of installing the known lifting / tipping mechanism stationary in the vicinity of the furnace, that is, for example, under the shaft, and lean the melting tank on a stationary holder. Also, the transmission device can be installed permanently. The trolley for changing the capacity is used only for changing the capacity. During the duty cycle, i.e. during operation of the melting furnace, the rail tracks and the wheels of the trolley to change the tank are practically unloaded, so that the danger that the wheels or rail tracks will undergo constant deformation in the working position is significantly reduced. The entire lifting / tipping mechanism, including its associated hydraulics, can be installed permanently. The trolley itself no longer needs hydraulics to change capacity. The drive of its movement can be performed purely electrically. Due to the significantly reduced masses, the power of the trolley movement drives for changing the capacity can thus be significantly reduced.

In accordance with the invention, the transmission device is implemented as follows. In the transfer position, the trolley for changing the tank is located under the melting tank in the working position. The carrier frame or, accordingly, its holder can be lowered relative to the trolley in the transmission position to change the tank or, accordingly, the base. The lowering of the melting capacity from the operating position occurs in such a way that during lowering the melting capacity will first snap onto the latch, i.e. on the trolley for the tank, and the trolley for the tank perceives the weight or, accordingly, the function of supporting the melting tank. Then, the carrier frame continues to lower, so that the melting vessel rises from the carrier frame and is disconnected from it.

The carrier frame in the sense of a transmission device must have only one perpendicularly acting lifting device. However, the combined lifting / tipping device in the supporting frame is ideal, since it also makes it possible to use tipping of the melting tank in the working position.

In one of the preferred embodiments, the container trolley is a rail vehicle, that is, has wheels that can be moved along a fixed track.

In another preferred embodiment of the invention, the travel path of the trolley for changing the container extends from the transmission position in at least two different directions. In other words, the trolley for changing the container in two different directions can move out of the furnace area. Namely, due to the stationary structure, in particular, it is possible to make a supporting frame like a bridge, under which a trolley for a container can pass. This gives greater flexibility to the design of the entire smelter or, accordingly, the corresponding use of the area. Thanks to the extended movement of the trolley for the tank, the workshop crane is unloaded, which leads to additional logistics benefits. In particular, in combination with vn rail vehicle rails for the trolley to change the capacity can be laid continuously under the supporting frame to implement paths of movement on both sides of the vicinity of the furnace.

In another preferred embodiment, the tank change trolley has a lock for the casting bucket. This ensures the double function of the trolley for the tank, since on the one hand, when the casting bucket is installed, it can be used for discharge, and on the other hand, for transportation of the melting tank. The installation requires only one single trolley in the form of a trolley to change the capacity and, thus, for example, only one single rail line. The latches for the casting ladle and the melting tank can either be interchangeably mounted on the main frame of the trolley to change the tank, or both can be constantly present in parallel without interfering with each other.

In this embodiment, the idea of the invention can be summarized as follows: the well-known so-called bucket trolley is transformed into a multi-function trolley, here called a capacity change trolley. The entire lifting and tipping mechanism for operating the furnace is permanently installed under the furnace. In principle, this kind of multifunctional trolley for this purpose should have a wider track than the well-known bucket trolley, but at the same time still pass into a stationary tipping mechanism, that is, a supporting frame. The multi-function trolley should then also be designed in such a way that the mechanism in the carrier frame can be used to mount the container on the bucket trolley. That is, a multifunctional trolley in comparison with known solutions should only be performed somewhat more massive. The necessary travel path or, accordingly, the travel path of the multi-function trolley can be reduced to a minimum, since it must be removed from the furnace area - to the parking position - only so that it is possible to remove the melting tank or casting ladle. At the same time, it is possible to avoid the aforementioned longer travel path of known trolleys for containers and bucket trolleys.

Other applications of the trolley for changing containers are also possible in alternative embodiments, for example, an additional lock for the slag vessel.

In another preferred embodiment of the invention, a container module is provided that comprises a melting tank and a frame portion rigidly connected to it. The carrier frame itself can then be made simpler, since in the working position, that is, with the capacity module installed, the frame part partially ensures the stability of the entire structure. The frame part has, for example, a work platform intended for passage, which covers the melting tank and which also has to undergo maintenance and, thus, can be removed or, accordingly, be serviced together with the melting tank. In this case, the entire module is always manipulated, i.e. the module is installed either on a supporting frame or on a trolley for a container or, accordingly, moves with the latter.

In another preferred embodiment, the container trolley includes, in addition, a mounting device mounted on it for the carrier frame or, accordingly, its components. Since, as a rule, there is a pit under the furnace, which, if necessary, serves for the placement of molten steel, this area under the furnace is poorly accessible by means of traditional maintenance vehicles. Therefore, dismantling one of the hydraulics components installed now stationary could be difficult. Therefore, the corresponding mounting device is, for example, a holding device for the hydraulic cylinder of the supporting frame. The mounting device can also serve for a melting tank located in the vicinity of the furnace or, accordingly, a tank module, for example, for a closing mechanism for the outlet. Thus, the multifunctionality of the trolley for changing containers is also provided here.

In the well-known electric melting furnace, the lifting / tipping hydraulics are generally made redundantly to ensure appropriate process reliability. According to one preferred embodiment of the invention, an emergency lifting device acting on the melting vessel and / or on the supporting frame can be mounted on the container trolley. Due to this measure, only a single execution of the lifting / tipping hydraulics of the supporting frame is possible, and in an emergency case, a tank for a tank with a mounted emergency lifting device can be brought in and, with its help, the melting tank or, respectively, the cart module can be lifted or placed again. The emergency lifting device can, for example, also act on the trolley module or the carrier frame holder. Therefore, to maintain technological reliability on the furnace plant itself, no more redundant tipping mechanism is required. In particular, the emergency lifting device can, for example, be combined with a dismantling device for a possibly faulty tipping cylinder on a tank trolley.

The corresponding emergency lifting device can, for example, operate purely electrically, so that for this no hydraulic components must also be mounted on the container trolley. For hydraulically operated, and only in rare emergency cases emergency lift, mobile hydraulic generator, which is not an integral part of the capacity trolley, can also be purchased to operate the emergency lift device in a serious case.

The concepts of the emergency lifting device as well as the mounting device, considered individually, could, for example, also be transferred to the well-known bucket carriage in traditional electric melting furnaces. There, one could also do without the redundancy of the existing hydraulic systems, for example, with the well-known trolley for containers. Installation work on a known trolley for a container or other furnace components could also be facilitated by means of mounting devices on a bucket trolley. In this sense, these embodiments are respectively independent of the above remaining embodiment of the electric melting furnace. Then the main idea is to no longer carry out the tilting and / or lifting mechanism that is redundantly redundant in a known electric melting furnace, and install the corresponding emergency lifting components and / or mounting devices on a mobile device, in particular a bucket trolley.

For a further description of the invention, reference is made to exemplary drawings. It is shown, in each case, on a schematic sketch in principle:

FIG. 1: an electric melting furnace equipped with a melting tank in the working position, and a trolley for changing the tank in the packaging position;

FIG. 2: part of the electric melting furnace of FIG. 1 equipped with a trolley for changing containers with an alternative lock;

FIG. 3: the system of FIG. 2 with a melting tank transported on a trolley to change the tank to the parking position;

FIG. 4: a part of the melting furnace of FIG. 1 when using a trolley to change the capacity as a bucket trolley in the exhaust position;

FIG. 5: the system of FIG. 2, equipped with an alternative trolley for changing containers with an emergency lifting device and a device for dismantling the hydraulic cylinder.

In FIG. 1 is a perspective view of an electric melting furnace 2, which essentially has a melting container 4, a lid 6 that covers this container from its upper side, and also a shaft 8 that serves to heat the not shown melted material. The melting container 4 is rigidly connected to the frame part 10 and forms together with her module 12 capacity. The frame part 10 is coated or, respectively, lined with refractory material. The module 12 of the tank and, at the same time, the melting tank 4 rests on a supporting frame 14, which is permanently mounted on the floor of the steel mill workshop not shown.

In FIG. 1 shows a melting vessel 4 in operating position A, in which it is integrated in an electric melting furnace 2 so that it can be used to melt steel scrap. The carrier frame 14 together with the container module 12 forms in cross section a U-shaped bridge under which the rails 16 are laid. On the rails 16 there is a trolley 18 for changing the container, so that it can move in the direction of the arrow 20 or against it. In FIG. 1 shows a trolley 18 for changing containers in the parking position P. A trolley 18 for changing the container from the parking position P in the direction of the arrow 20 can be moved to the one indicated in FIG. 1, the dashed line indicates the transfer position x, in which it is substantially completely under the melting tank 4. The rails 16 form a path 17 of movement that extends from the electric furnace 2 in two different directions 19 a, b, namely, in the direction of arrow 20 and against him. The trolley 18 for changing the container can thus, starting from the transmission position Ü, move in two directions 19 a, b.

The trolley 18 for changing the capacity has a latch 22 in the form of four supports 24, on which the melting capacity 4 or, accordingly, the entire module 12 of the trolley can be installed. The electric melting furnace 2 comprises a transmission device 26 in the form of a lifting mechanism 28 formed by several hydraulic cylinders 30. The supporting frame 14 is divided into an upper holder 34 and a base 36. The upper holder 34 is movably held relative to the stationary base 36 by means of a lifting mechanism 28. Strictly speaking, the module 12 capacity relies only on the holder 34 of the supporting frame 14.

In FIG. 2 in addition to FIG. 2, in a side view along arrow II, an electric melting furnace 2 of FIG. 1, here, however, only the tank module 12 and the supporting frame 14 with the base 36 and the holder 34 and hydraulic cylinders 30. The cart 18 for changing the tank in FIG. 2 shows in one of the alternative embodiments with additional supports 38, which form an alternative latch 22 for the melting tank 4 or, accordingly, the module 12 of the tank.

When the trolley 18 for changing the container is in the transfer position Ü, using the transfer device 26, the melting tank 4 or, accordingly, the entire module 12 of the container can be lowered in the direction of arrow 32 relative to the other components of the electric melting furnace 2 and the trolley 18 for changing the container. The melting tank 4 is then mounted on the latch 22. When further carried out by the transmission device 26, lowering the carrier frame 14 in the direction of arrow 32, the latter is disconnected from the module 12 of the vessel or, respectively, the melting vessel 4, and it is disconnected from the carrier frame 14. Then it rests only on the cart 18 to change the capacity. The various supports 40 belonging to the supporting frame 34, which can support the holder 34 in different positions, are completely rotated along arrows 42 to allow the holder 34 to be completely lowered in the direction of arrow 32.

After the module 12 of the tank is released or, respectively, disconnected from the carrier frame 14 or, respectively, from the holder 34, it can, together with the trolley 18 for capacity against the direction of arrow 20, again move to the parking position P. In FIG. 3, this situation is shown in the image in accordance with FIG. 2 together with the supporting frame 14 completely lowered in the direction of the arrow 32 or, respectively, the holder 34 and the supports 40 fully turned.

In FIG. 4 shows essentially the components of FIG. 2, 3 in the image in accordance with FIG. 1. It can be seen here that the melting vessel 4 consists of a lower vessel 44 lined with refractory material and consisting of the panel walls of the upper vessel 46. In FIG. Figure 4 shows, in addition, one of the alternative embodiments of the container change trolley 18, which further has a latch 48 for the casting bucket 50. The container change trolley 18 is also located here in the outlet position S located between the parking position P and the transfer position x. In this case, the casting bucket 50 is located under the outlet port of the melting tank 4 not shown. Here, the lifting mechanism 28 simultaneously has a tipping function, while the hydraulic cylinders 30 can be actuated in various ways. The discharge is then carried out by tipping the holder 34 together with the container module 12 about the tipping axis 53 in the direction of the arrow 54. In particular, the melting container 4 is tipped so that the steel melt not shown through the outlet flows into the casting ladle 50. For this, in addition to moreover, the correspondingly longer, facing the trolley 18 for the capacity of the support 40 rotate in the direction of the arrows 42. The two shorter of the respective supports 40 remain in the shown in FIG. 4 position. Then, in the tipping position, the holder 34 or, accordingly, the module 12 of the tank relies on these supports. This prevents further tipping over and provides a predetermined inclined position of the melting tank 4.

In FIG. 5 shows another alternative embodiment of a trolley 18 for a container. This trolley is equipped with 56 emergency lift device. For example, if the hydraulic cylinders 30 fail in the aforementioned tipping position when the trolley 18 for the container approaches the electric melting furnace 2, it is possible to place the emergency lifting device 56 under the holder 34, the supporting frame 14 or the melting capacity 4. Then, the supporting frame 14 together with the capacity module 12 using the emergency lift device 56, it again rises back to the initial position shown. The embodiment of the lifting mechanism 28 shown in all the figures may be implemented as follows. In each case, only one single hydraulic cylinder 39 is provided in one place of the supporting frame 14. This is the opposite of the known lifting devices, in which the hydraulic cylinders 30 should always be made in pairs redundant, which is necessary to ensure the technological reliability of the electric melting furnace 2. Due to the presence of emergency lift devices 56 can do without redundant hydraulic cylinders 30.

In FIG. 5 shows another alternative embodiment of a tank trolley 18, in which the trolley comprises a mounting device 58. In this example, the mounting device 58 is a device for dismantling the hydraulic cylinders 30. As the trolley 18 for the tank or, accordingly, the mounting device 58 approaches the hydraulic cylinder 30, this hydraulic cylinder can be held. Then, the hydraulic cylinder can be disconnected from the rest of the structure of the supporting frame 14 and with the help of the trolley 18 for changing the tank, as shown in FIG. 5, exported or, accordingly, replaced.

Claims (21)

1. An electric melting furnace (2), comprising a stationary mounted support frame (14) and a melting tank (4) resting on this frame in the operating position (A),
trolley (18) for changing the tank, moved between the parking position (P) and the transmission position

having a latch (22) for the melting tank (4),
disconnecting melting tank (4) in the transfer position

from the carrier frame (14) and the transmission device (26), which is installed in the latch (22) of the carriage (18) for changing the capacity, while the carrier frame (14) can be lowered relative to the transmission position by means of the transmission device (26)

bogies (18) for changing the container from the operating position (A) in such a way that during lowering the melting tank (4) is first installed on the latch (22), and then, rising from the carrier frame (14), is disconnected from it, and the carrier the frame is equipped with supports (40), made with the possibility of full reclining. 2. An electric melting furnace (2) according to claim 1, comprising propagating from the transmission position

in at least two different directions (19a, b) the path (17) of the movement of the trolley (18) for changing the tank. 3. An electric melting furnace (2) according to claim 1 or 2, wherein the trolley (18) for changing the container has a latch (48) for the casting bucket (50). 4. An electric melting furnace (2) according to claim 1 or 2, comprising a vessel module (12), comprising a melting vessel (4) and a frame part (10) rigidly connected to it. 5. An electric melting furnace (2) according to claim 3, comprising a vessel module (12), comprising a melting vessel (4) and a frame part (10) rigidly connected to it. 6. An electric melting furnace (2) according to claim 1 or 2, comprising a mounting device (58) mounted on a trolley (18) for changing the capacity for the support frame (14) and / or the melting vessel (4). 7. An electric melting furnace (2) according to claim 3, comprising a mounting device (58) mounted on a trolley (18) for changing the capacity for the support frame (14) and / or the melting vessel (4). 8. An electric melting furnace (2) according to claim 4, comprising a mounting device (58) mounted on a trolley (18) for changing the capacity for the supporting frame (14) and / or the melting vessel (4). 9. An electric melting furnace (2) according to claim 5, comprising a mounting device (58) mounted on a trolley (18) for changing the capacity for the supporting frame (14) and / or the melting vessel (4). 10. An electric melting furnace (2) according to claim 1 or 2, comprising an emergency lifting device (56) installed on a trolley (18) for changing the tank, acting on the melting tank (4) and / or the supporting frame (14). 11. An electric melting furnace (2) according to claim 3, comprising
mounted on the trolley (18) for changing the tank, acting on the melting tank (4) and / or the supporting frame (14) emergency lifting device (56). 12. An electric melting furnace (2) according to claim 4, comprising an emergency lifting device (56) installed on a trolley (18) for changing the tank, acting on the melting tank (4) and / or the supporting frame (14). 13. An electric melting furnace (2) according to claim 5, comprising an emergency lifting device (56) installed on a trolley (18) for changing the tank, acting on the melting tank (4) and / or the supporting frame (14). 14. An electric melting furnace (2) according to claim 6, comprising an emergency lifting device (56) installed on a trolley (18) for changing the tank, acting on the melting tank (4) and / or the supporting frame (14). 15. An electric melting furnace (2) according to claim 7, comprising an emergency lifting device (56) installed on a trolley (18) for changing the tank, acting on the melting tank (4) and / or the supporting frame (14). 16. An electric melting furnace (2) according to claim 8, comprising an emergency lifting device (56) mounted on a trolley (18) for changing the tank, acting on the melting tank (4) and / or the supporting frame (14). 17. An electric melting furnace (2) according to claim 9, comprising an emergency lifting device (56) mounted on a trolley (18) for changing the tank, acting on the melting tank (4) and / or the supporting frame (14). 18. An electric melting furnace (2) according to claim 1 or 2, wherein the trolley (18) for changing the capacity is a rail vehicle. 19. An electric melting furnace (2) according to claim 3, wherein the trolley (18) for changing the capacity is a rail vehicle. 20. An electric melting furnace (2) according to claim 6, wherein the trolley (18) for changing the capacity is a rail vehicle. 21. An electric melting furnace (2) according to claim 7, wherein the trolley (18) for changing the capacity is a rail vehicle.

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