MXPA97001452A - Automatic system for the connection of pneumatic and hydraulic hoses on a mixed electrode for ovens of a - Google Patents

Abstract

The present invention relates to a system for connecting at least one of pneumatic hoses and hydraulic hoses on composite electrodes for arc furnaces, comprising at least one electrode, each electrode having at least one hollow adapter associated in its part lower with a replaceable graphite element, each electrode that cooperates with an electrode support arm and is displaceable axially relative to the electrode arm, the hoses that are associated at one end with a first connection assembly associated with support means, the adapter including a second connection assembly solidly connected functionally coinnt with the first connection assembly, the first and second connection assemblies comprising matching connecting elements equipped with elements for automatically interrupting a fluid flow and capable of being temporarily activated, the system that is characterized because the means of s The ports associated with the first connection assembly have a first inactive position connected to the electrode support arm and a second working position released from the electrode support arm and connected to the second connection assembly, a transition from the first inactive position to the second working position of the support means that takes place according to an electrode placement in a defined position of coupling and decoupling

Description

AUTOMATIC SYSTEM FOR THE CONNECTION OF PNEUMATIC AND HYDRAULIC HOSES ON AN ELECTRODE MIXED FOR ARC OVENS DESCRIPTION OF THE INVENTION This invention relates to an automatic system for the connection of pneumatic and hydraulic hoses on mixed electrodes for arc furnaces, as set out in the main claim. To be more exact, the automatic connection system according to the invention is used for the connection of hoses that transport cooling and actuating fluids to the cooled adapter element on electrodes of a mixed type used in electric arc furnaces. The invention is used both in electric arc furnaces fed with direct current and with those fed with alternating current. The system according to the invention helps, accelerates, and automates the connection / disconnection operations of the hydraulic and pneumatic hoses during the steps of removal and replacement of the electrodes. Furthermore, the system according to the invention does not cause any impediment to the vertical movement of the electrodes during the operational steps of the furnace, since, at least during these operational steps, the connecting assembly of the hydraulic and pneumatic hoses is integrated with the electrode and moves vertically with it. The state of the art includes mixed electrodes formed with a hollow cylindrical adapter made of a metallic material, and secured to the electrode support arm; A consumable cylindrical graphite element is fixed to the lower end of the adapter element, from which the electric arc is ignited. The electrode of a mixed type provides several advantages, compared with those made entirely of graphite; The adapter in a direct current fed furnace can have the function of an auxiliary reactor, thus reducing the size and complexity of the external reactors normally used in the plant supplying said furnaces. The adapter, appropriately sized, in a furnace fed with alternating current, allows the currents circulating in the three phases to be balanced, thus reducing the disadvantages of the state of the art that arise from an unbalanced system. An additional advantage provided by the use of mixed electrodes is that they do not require prior processing for the adaptation of the graphite element, for this processing it is necessary, rather, electrodes made entirely of graphite; The reason for this is that the electrode is supported by the electrode support arm in the adapter, and not in the graphite element.

The lack of prior processing makes possible an enormous saving of material, costs and processing times. On the other hand, said mixed electrodes require a system to cool the adapter, in order to avoid that the latter is capable of being damaged due to the high temperature of the oven. The cooling of the adapter is normally done by circulating inside it a cooling fluid, usually air or water, which is fed through external hoses. According to the state of the art, these hoses are free and flexible, and are secured at one end to the upper part of the adapter. However, it is known that the electrodes, during the work cycle, have to be able to slide axially relative to the electrode support arm, to adjust the height of the electrodes relative to the molten metal bath, in accordance with the wear of the graphite segment, and also have to be able to be disassembled quickly and easily, in order to make possible the normal maintenance and replacement operations of the graphite segment. The cooling hoses form a great obstacle, since they have to be disconnected to perform the electrode removal operations. Actually, as it is possible to adjust the axial position of the electrode, the disassembly of the electrode is especially difficult since the disconnection of the sleeves has to be done with the hand Also, to perform this operation, the operator of the machine has to climb on the electrode support arm and in this way be exposed to the risk of accidents and infringe the specific safety rules in force. In order to avoid this problem, the hoses are equipped with connection means to adjust the axial position of the electrode. According to this embodiment, the hoses are connected to a first connection assembly, which includes a plurality of elements that connect the hoses, and is solidly fixed to the electrode support arm. The adapter element of the electrode includes a second connection assembly, which is solidly fixed to the upper part of the adapter and coincides with the first connection assembly and is connected to the cooling conduits located within the latter. Both connection assemblies include automatic closing means, which prevent the fluid contained therein from leaving the hoses when the connection assemblies are disconnected. When the electrode is lowered to its working position, the second connection assembly, located on the electrode, cooperates with the first connection assembly placed on the electrode support arm, thus allowing the cooling fluid to circulate inside the adapter. .

Vice versa, when the electrode is raised to its inactive position, the two connection assemblies are disconnected and release the electrode. This mode makes it possible to easily disassemble the electrode to carry out the maintenance and replacement of the graphite segment, but it does not make it possible to adjust the axial position of the electrode, since each displacement of the electrode causes the uncoupling of the connection assemblies, between them, and the resulting interruption of the circulation of the cooling fluid. EP-A-0167485 shows a device, substantially of the type described above, which serves to assist and accelerate the connection of the cooling water hoses after each electrode replacement. This device comprises a connection assembly, which is fixedly attached to the arm supporting the electrode; the assembly is connected on one side to the hoses that supply the cooling water, and on the other side includes openings for the insertion of conduits for the water supply, these conduits being connected to the electrode adapter. Also included is a guide element, attached to the adapter, by means of which the water supply conduits are guided inside the connection assembly, during the step of placing the new electrode, until the conduits are connected. with the assortment hoses. This mode, if, on the one hand, it helps the connection operations of the various elements each time the electrode is changed, does not allow the electrode to be moved vertically, once the connections have been made, in order to adjust the length of the electrodes in the course of the melting process inside the furnace. This is because the connection assembly is fixed on the electrode support arm, and therefore can not move with the electrode and follow its vertical adjustment movements. So to overcome the disadvantages of the state of the art, detailed above, and to obtain other advantages, the applicants hereof have designed, tested and modalized this invention. The invention is set forth and characterized in the main claim, while the dependent claims describe variants of the idea of the main mode. The purpose of this invention is to modalize, in a mixed electrode including a cooled adapter associated in the lower part with at least one segment of graphite, a system for connecting the pneumatic or hydraulic hoses that perform the cooling and / or the power transmission, the system allowing fully automatic operations to connect / disconnect the various elements. A further purpose of the invention is to obtain a system that includes an assembly for connecting the hoses, which, in the operational position of the electrode, is integrated with the cooled adapter and, therefore, can follow the movements of the electrode as This is adjusted vertically, as the melting cycle of the furnace progresses and according to the progressive wear of the graphite segment. According to the invention, the system comprises a first connection assembly, to which the hoses transporting the cooling fluid and possibly also a driving fluid are connected. This first connection assembly is associated with the support means, which have a first inactive position, assumed at least in the steps of replacement or maintenance of the electrode, where they are solidly attached to the support arm of the relative electrode by means of subjection. This secure positioning of the support means on the electrode support arm ensures that, as long as the electrode is disconnected from the furnace and the supply of cooling fluids is interrupted, the first connection assembly has a secure and stable position. The system according to the invention also includes a second connection assembly, solidly associated with the electrode adapter, usually near the top of the adapter. The configuration of this second connection assembly is substantially coincident with the first connection assembly. To be more exact, the second connection assembly includes connection openings for the passage of fluid, the openings being located in positions corresponding to the matching openings on the first connection assembly. In addition, the second connection assembly includes connections to the conduits for the fl uids, both cooling fluid and drive fluid, within the adapter. The complementary openings that provide the connection and passage of the fluid, which are included in the first and second connection assemblies, are equipped with automatic closing devices, which interrupt the passage of the fluid when they are not connected between them. In addition, the first and second connection assemblies are equipped with matching, reciprocal coupling / decoupling means, which are automatically actuated. In the system according to the invention, when the electrode is progressively lowered to be placed in its working position, the second connection assembly, solid with the adapter, is placed in cooperation with the first connection assembly, which in that moment is fixedly placed on the electrode support arm. This cooperative position automatically causes the release of the support means on the first connection assembly of the electrode support arm, and at the same time, the coupling of the support means to the second connection assembly, which is solid with the adapter.

In this form, the first connection assembly assumes a second solid working position with the electrode, enabling free movement and adjustment of the axial position of the electrode during the work cycle; all the hoses connected to the first connection assembly follow the electrode in its axial movement. According to a variant, the release of the support means of the first connection assembly from the electrode support arm, and the coupling of the support means to the adapter, are remotely controlled during the passage in which the electrode is it goes down to its operating position and the first and second assemblies are in their reciprocal cooperation position. The decoupling of the electrode from the cooling hoses, connected to the first connection assembly, takes place in reverse fashion by repositioning the electrode in the coupling / uncoupling position. At the same time, and automatically, the support means of the first connection assembly is released from the adapter and reconnected to the electrode support arm, thus enabling the release of the second connection assembly, which is solid with the adapter , of the first connection assembly and in this way the dismantling and removal of the electrode. The appended figures are presented as a non-restrictive example, and show a preferred embodiment of the invention, as follows: Figure 1 is a three-dimensional view of a mixed electrode equipped with an automatic connection system according to the invention; Figure 2 shows an example of a side view of the mixed electrode of Figure 1, in its inactive position with the first connection assembly anchored to the electrode support arm; Figure 3 shows the same side view of Figure 2, with the electrode lowered to the coupling / uncoupling position; Figure 4 shows the same side view of Figure 2, with the first connection assembly secured to the electrode. The reference numeral 10, in the appended figures, generally denotes an automatic system as a whole for the connection of pneumatic or hydraulic hoses 1 1. The reference number 12 denotes an electrode of a mixed type, which consists of a hollow cooled adapter 13, made of a metallic material and a consumable and replaceable segment 14, made of graphite. The adapter 13 contains conduits, not shown here for the transport and passage of cooling fluids and power supply. The electrode 12 is supported by an electrode support arm 15, by means of a fastener and can slide axially relative to the arm 1 5, in order to alter, as the fusion cycle proceeds, the distance of the segment of graphite 14 from the molten metal bath to the interior of the furnace; and to allow the electrode 12 to be removed, when it is necessary to replace it, maintain it or integrate it into the graphite segments 14. The elevation of the electrode 12 is done in a known manner, by means of an appropriate crane by means of a hook 16. According to With the invention, lower attachment means 23 are provided on the electrode support arm 15, and support means 17 cooperate with these lower attachment means 23 by matching coupling means 24. On the support means 17, there is a first connection assembly 18a, to which the hoses 1 1 carrying cooling fluid and possibly a fluid for operating actuators or other drive systems possibly included within the adapter 13 are attached. The first connection assembly 18a comprises a plurality of first elements of connection 19a, equipped with means for interrupting the flow of the fluid, which are not shown here. A second connection assembly 18b is solidly fixed to the adapter 13 by means of a bracket support 21 and comprises a plurality of second connection elements 19b, which coincide in number and in position with the first connection elements 19a included in the first connection assembly 18a. These second connection elements 19b also include n means for interrupting the flow of fluid, which are not shown here. On the adapter 13 are included guide means 20 which prevent rotation of the electrode 12, thus maintaining the first and second connection assemblies 18a, 18b aligned during the axial movement of the electrode 12. The electrode 12 is lowered from its inactive position elevated, which can be caused for maintenance or replacement operations, which is shown in Figure 2, towards its coupling / uncoupling position, shown in Figure 3, thus leading the second connection assembly 18b to cooperate with the first connection assembly 18a. In this case, a release actuator 22, placed on the mobile support means 17, causes the automatic decoupling of the mobile support means 17 from the electrode support arm 15, and at the same time, causes the means of movable support 17 are coupled with the support 21. To be more exact, in this case, this coupling takes place by means of an automatic connection between the first coupling elements 25 included on the mobile support means 17, and the second joining means 26 included on the underside of the support 21. According to a form of the embodiment of the invention, the actuation of the actuator 22 can be governed by a sensor 27, which identifies the end-of-path position of the electrode 12, with the second connection assembly 18b located in cooperation with the first connection assembly 18a. According to another embodiment of the invention, this coupling / uncoupling can be completely mechanical; the mere descent of the electrode 12 causes the mechanical coupling between the first and second connection assemblies 18a, 18b, while the elevation of the electrode 12 causes mechanical decoupling between the first and second connection assemblies 18a, 18b, according to a configuration analogous to that of "pens or biros" by means of an oppressible button. Once the first connection assembly 18a has been anchored to the second connection assembly 18b and, therefore, to the adapter 13, and once the relative connection elements 19a and 19b have been connected, the means for interrupting the flow of fluid are deactivated and the cooling fluid and the drive fluid are allowed to flow. The position of the first solid connection assembly 18a with the adapter 13 allows the electrode 12 to move axially in a completely independent manner, both from the position where the hoses 1 1 are connected, and also from the position of the support arm of electrode 15. Figure 4 shows an example of a possible position, which electrode 12 can assume, since the first connection assembly 18a is solid with the electrode 12. According to a variant, the decoupling of the mobile support means 17 from the electrode support arm 1 5, and the coupling of the mobile support means 17 with the support 21 are performed by means of actuators. 22 respective, and separated.

According to another variant, coupling / uncoupling are remotely controlled by a machine operator. The decoupling of the electrode 12, from the hoses 11, is carried out by returning the electrode 12 to the coupling / uncoupling position, ie, bringing the support means 17 back to a position where they cooperate with each other. the electrode support arm 15. In this position, the decoupling actuator 22 releases the mobile support means 17 from the bracket support 21, and at the same time, reassembles the mobile support means 17 to the support arm of the electrode 15, thereby allowing the uncoupling of the first and second connection assemblies 18a, 18b, from one another, after reactivating the means for interrupting the flow of the fluids associated with the connecting elements 19a, 19b. As described above, the system 10 for connecting hoses 1 1, according to the invention, takes place in a fully automatic manner, without requiring manual action by the personnel in the electrode support arm 1. situation makes the operations of assembling and disassembling the electrode fast and safe, and eliminates the problems described above and forms the set of demands of businessmen in this field for a long time. At the same time, the axial movement of the electrode 12 is in no way damaged or impaired during the operation steps of the furnace, since the graphite segment is progressively consumed.

Claims (10)

1 .- A system for the connection of pneumatic and / or hydraulic hoses (11) on mixed electrodes (12) for arc furnaces, the electrodes (12) comprise at least one hollow adapter (13) associated in the lower part with a replaceable graphite element (14), the electrode (12) cooperating with an electrode support arm (15) and being axially displaceable relative to said electrode support arm (15), the hoses (11) being associated at one end with a first connection assembly (18a) associated with support means (17), the adapter (13) including a second connection assembly (18b) solidly joined, functionally coinciding with the first connection assembly (18a) , the first (18a) and second (18b) connection assemblies comprise matching connection elements (19a, 19b) equipped with elements to automatically interrupt the flow of fluid and capable of being temporarily activated, the system characterized in that the Supporting members (17) associated with the first connection assembly (18a) have a first temporarily inactive solid position with the electrode support arm (15) and a second working position released from the electrode support arm (15) , and temporarily solid with the second connection assembly (18b) associated with the adapter (13), the transition from the first inactive position to the second working position of these support means (17) takes place in accordance with the placement of the electrode (12) in a defined coupling / uncoupling position.

2. The connection system of claim 1, wherein the support means (17) include lower coupling means (24), capable of being temporarily activated and cooperating, in the first inactive position, with the lower attachment means coinciding (23) included on the electrode support arm (15) and also include upper coupling elements (25), capable of being temporarily activated and cooperating with the matching joining means (26) included on the adapter (13) in the second work position.

3. The connection system of claim 1 or 2, wherein the coupling / uncoupling, between the coupling / coupling means (24, 23, 25, 26) takes place mechanically, according to the descent of the electrode to the coupling / uncoupling position.

4. The connection system of claim 1 or 2, wherein the upper (25) and lower coupling means (24) of the support means (17) are governed by at least one release actuator (22) .

5. The connection system of claim 4, wherein the actuator (22) is remotely controlled.

6. The connection system of claim 4, wherein the actuator (22) is governed by a sensor that identifies the end-of-path position of the electrode (12).

7. - The connection system of any of the preceding claims, wherein the adapter (13) comprises axial guide means (20) capable of aligning and centering the first (18a) and second (18b) connection assemblies.

8. The connection system of any of claims 1 to 7, inclusive, wherein the union / release actuator (22) is of a hydraulic type.

9. The connection system of any of claims 1 to 7, inclusive, wherein the union / release actuator (22) is of a pneumatic type.

10. The connection system of any of claims 1 to 7, inclusive, wherein the union / release actuator (22) is of an electrical type.