WO1992004149A1 - Method for automatically supplying, checking and placing refractory bricks in metallurgical reactors and vessels - Google Patents

Abstract

A device is provided for lining the inside of metallurgical reactors and vessels with refractory bricks, said device being characterized in that it can, in a self-contained manner, supply the materials, control their quality and remove rejects as appropriate, place each brick in the lining according to a specific programme determining the form of lining to be obtained, and continuously form an expansion joint outside the wear wall being built. For this purpose, the main operative portion of the device is composed of a vertical tower placed on the vessel to be constructed and unsupported therein. Said tower supports a translatable carriage within the vessel for the stepwise positioning of a brick placing arm. The materials are supplied from a depalletizing conveyor, pass through a device for checking them individually, and are transferred to the tower on the vessel to be lined. They are transported to the point where they are to be placed by a circular feeder platform, a vertical supply conveyor and a moving belt connected to the brick placing arm. This arm receives the bricks one at a time and places them accurately in order to form a continuous wall. All of these operations are performed without human intervention.

Description

 AUTOMATIC PROCESS FOR SUPPLYING, MONITORING AND ASSEMBLING REFRACTORY BRICKS in REACTORS or CONTAINERS FOR METALLURGICAL USE

The process which is the subject of the invention relates to a fully robotic device, allowing the internal lining in refractory bricks of reactors or containers for metallurgical use, mainly but not exclusively the containers which allow the transport and the pouring of liquid metals. , which is designated by the term "ladles".

The process according to the invention is particularly useful because it performs all the sequences and operations which are, in accordance with the prior art, carried out in a difficult working environment and conditions by masons in a fully automatic manner. specialists in the field of industrial fumigation.

The general designation of the operations and sequences that this device performs respectively is as follows:

- the supply of bricks, the format of which can vary during the same assembly, by gripping them from the pallets where they are stored

- the geometric control and sorting of these bricks continuously, according to their dimensional specification required by the lining, that is to say the adequacy of each brick according to the future position it will occupy in the wall of the container

- continuous quality control of each brick, by measuring its physical properties and excluding them from the assembly cycle if the material does not comply with predefined standards

- the transfer of these bricks without human intervention inside the enclosure or the container during masonry

- the removal of each brick according to a pre-established program and which respects the shape of the wall to be produced

- the continuous manufacture on the upper surface of the lining of an expansion joint in powder material. The subject of the invention is a process which is particularly useful for the internal production of wear linings in refractory bricks for steelworks pockets, pockets used in the preparation and transport of liquid metal.

In accordance with the prior art, the manual lining of these steel bags in refractory bricks is still in use. It is carried out by specialized personnel who use bricks whose shapes and dimensions are constantly subjected to numerous adaptations according to the metallurgical function which the container must fulfill.

In the case of steel metallurgy, experience has shown that these industries for the most part now prefer wear linings in so-called "basic" bricks. Most of these bricks are bricks composed of cooked or tempered magnesia, carbon-magnesia, magnesia-dolomite or cooked or tempered dolomite. The role of these qualities, however diverse they may be, is to constantly adapt the wear of the coating to chemical and thermal stresses, very severe stresses that the bags used nowadays as reactors for producing metal undergo.

It is clear that there is considerable technical and economic interest when the production of the coating can be carried out with the greatest care. The metallurgist wishes a great reproducibility in the making of his wear lining, by ensuring the most perfect internal tightness of the container against liquid metal infiltrations, infiltrations fatal to the life of this one.

Advantageously, the process which is the subject of the invention guarantees this quality and this perfect reproducibility in the making of the brick lining. According to the current state of the art in manual assembly processes, the difficult conditions of unsanitary work of workers in hot and dusty atmospheres, cause imprecise, risky and unreliable assemblies.

The main purpose of the invention is to eliminate this arduous nature of the work of men who must work in these extremely confined places by penetrating inside the containers. They undergo conditions of intense heat there, dangerous dusts obliging them to the permanent port of respiratory masks. It is clear that this important characteristic of the invention will eliminate the majority of bodily accidents during the work of operators, very numerous accidents during the fall of bricks, during their manual manipulation during their transfer or their implantation in the container.

Other characteristics of the invention will appear on reading the following description and, in particular by way of example, a more detailed description of the entire device shown during the construction of an internal wall of a pocket. steelworks, made with reference to Figures 1 to 4 of the accompanying drawings in which:

Figure 1 schematically shows all the organs of the instal¬ lation in a first embodiment.

Figure 2 shows the depalletization manipulator and the brick model used in the example.

Figure 3 shows in more detail the brick routing and control line.

FIG. 4 represents the brick stacking manipulator in the working position in the pocket.

The invention can be better understood from this particularly useful application of the method, application which describes below, the cycle of setting up a standard brick model marketed by producers of refractory materials. The brick shape described in 6 in FIG. 2 is one of the most commercial geometrical shapes and it is the one that was used in this example.

In accordance with the prior art, this form of brick makes it possible to generate, by its manual deposit in scrolls, most of the radii of gyration of the refractory wall, radii varying according to the different pocket volumes. It is clear that there is considerable economic interest in using with the device which is the subject of the invention, the brick formats most widely used in manual assembly. However, it should be noted that the format taken here as an example is not exclusive to the device presented and that the method according to the invention applies to other models and formats of bricks or shaped refractory pieces.

The description which follows as an example gives, without any limiting character, an illustration of the advantages of the complete device. APPLICATION EXAMPLE

The device which is the subject of the invention is developed in its entirety according to FIG. 1 .11 comprises the three main parts described respectively according to FIGS. 2, 3, and 4. The description below in the example confers the construction of a refractory wall made of magnesia and magnesia-carbon bricks for metallurgical vessels in pockets, vessels with a capacity of more than 80 tonnes of liquid steel

The container to be lined is placed in a construction pit, this in order to avoid brick transfers in too distant horizontal planes.

The depalletizing robot and the brick control unit have been voluntarily shown in separate sets to better understand the device which is the subject of the invention. All the mechanisms are under the control of a central computer which manages the cycle automata, and which processes all the information necessary for the proper accomplishment of tasks in real time, it is also responsible for monitoring the use of materials and their accounting allocation in inventory monitoring.

Figure 2 describes depalletization. A manipulator robot (1) grips the bricks according to four pallet storage areas. These pallets generally have a useful surface for removing bricks of 1200 mm x 1200 mm. This gripping is ensured in this example by suction cups (15) mounted on a transfer carriage (14) itself movable in rotation on its support barrel (13) mounted on a carriage (12). The assembly covers with the raceway (11) a surface with a grip angle of 180 °. The raised brick is placed on the transfer in (5).

The performances chosen for the trips are as follows:

- Movement speed along the X and Y axes: _ 1 m. s ^" '

- Lifting speed of the gripper: ≥ 0.3 m. s ^"1

Drum rotation speed (at its end): ≥ 0.6 m. s -1

The parts are supplied individually at high flow rate according to the program defined in the computer. Advantageously, the routing of bricks of different formats and qualities can be carried out according to their precise destinations in construction. Figure 3 describes the brick routing and control line. Very advantageously the machine operates a continuous and systematic control on all of these. This control is autonomous and allows the materials to be validated piece by piece before their final transfer to the stack.

The bricks, after being placed on a feeding belt, enter a protected enclosure (21), where their shapes and dimensions are checked. This control can be done, for example, by a camera specialized in these tasks, a shape recognition video camera. Connected to the calculator, this camera gives the information necessary to organize the scrap (broken corners, shape not corresponding to the mounting indices).

Weighing (23) is performed for density control during the shape control operation. After measuring its physical characteristics, the brick is transferred to the evacuation table (24) where its disposal is carried out if necessary, by a drawer (25). A lifting chain (26) then transfers this brick to the stack.

Figure 4 explains the active part of construction of the lining in the container. Very advantageously, the process is based on the principle of the continuous introduction of materials, without there being at any time the introduction of pallets or packages of bricks inside the container. This stacking manipulator according to Figure 4 consists of a vertical tower (31) which is completely removable and introduced by a lifting means into the container to be built. This introduction can for example be done using a lifting crane. This tower is placed on the container in a horizontal plane (P _H ). It pivots along an axis of gyration (P _v ).

All of the mechanisms of this vertical tower (31) are suspended, without support or support with the interior of the container. The support points of this vertical mechanism and therefore its three-dimensional geometric references are located outside the metal tank.

This advantage sought in the invention makes it possible to overcome all the drawbacks and location errors which are the case with the current state of the art of manual construction carried out by operators. According to a preferred embodiment in the invention, a transfer band (34) feeds a rotary circular plate (37). This plateau rotates around the axis of gyration (P _v ). Very advantageously, it offers the possibility of feeding the transfer chain (35) by the pneumatic cylinder (36), both integral in rotation with the vertical tower (31) and whatever the angular position of this tower around the 'axis (P _v ).

At the desired moment, when a brick is presented in position by the rotary plate (37), the jack (36) pushes this brick into a cell of the chain (35) which descends this brick towards a horizontal belt (40) supplying the manipulator (33) which will position it in the wall.

The carpet (40) and work manipulator (33) assembly is vertically translated by the carriage (32), itself integral in rotation with the tower (31). The combination of these simple movements, generated by a "step by step" movement, guarantees the precise laying of the bricks at the desired location in the wall. A position sensor (41), which can for example be an opto-electronic sensor, permanently informs the computer of the azimuthal situation of the point of removal of the brick for perfect control of the stacking of the wall, according to, but not exclusively, stacking in scrolls (helicoid) in one or more steps in the case of the application example.

According to another characteristic of the invention, provision can be made to continuously form an expansion joint (39) necessary during the rise at very high temperature of the lining during use of the container. This joint is made on the upper surface of the brick wall by a free interval of 10 to 30 mm, continuously filled with a powdery refractory mass using a nozzle (42), positioned at the end of a flexible tube and pre-adjusted at the start of assembly. In the case of the example, the pulverulent product used can be a dolomite or magnesia powder. This powder is stored in a container (38) located at the top of the vertical tower (31) of which it is integral in rotation. This characteristic allows, if necessary, the filling of additional quantity of refractory powder in the container (38), this during the current stacking cycle and without disturbance.

Claims

1) Process for the automatic production of a lining of refractory bricks in metallurgical reactors or containers, characterized in that a completely autonomous device is used which does not require any manual intervention by operators inside the container. 2) Method according to claim 1, characterized in that the device consists of a brick depalletization chain, a continuous material control chain and a vertical rotary tower, introduced into the container to be garnished and fixed on the external part of it, this tower supporting by its mast the stacking manipulator 3) Method according to claims 1 or 2, characterized in that the bricks are supplied one by one, without human intervention, from their storage area on pallets, to the depositing manipulator working in the container. 4) Method according to claim 3, characterized in that a piece-by-piece control is carried out on these bricks during this supply and that this control comprises a dimensional measurement and a measurement of the physical characteristics of the materials. 5) Method according to claim 1 or 2, characterized in that the working tower is introduced and suspended vertically in the container, and that the points of removal and fixing of this tower on the container are external to this container. 6) Method according to claim 1 or 2 or 5, characterized in that this tower supports its own device for supplying bricks, distributed piece by piece by a circular plate, and that this device is in rotational movement around a vertical axis of gyration. 7) Method according to claim 5 or 6, characterized in that the internal mast of this tower is without contact with the interior of the container and that this mast supports a forklift which is integral with it in rotation, the carriage itself provided with a vertical translational movement. 8) Method according to claim 7, characterized in that the active extremity of the arm of this internal carriage supports a brick stacking manipulator whose displacement of a step by step type, generates the making of the refractory wall , from the bottom to the top of the container, as well as a device for continuously making thermal expansion joints, back to this wall. 9) Method according to claim 7 or 8, characterized in that the azimuthal position of the drop point of each brick is controlled by sensors whose permanent information allows to perform a precise auto¬ correction of this drop point by a loop d position control, loop managing the movement of the brick manipulator. 10) Method according to claim 8, characterized in that the expansion joint external to the refractory lining of wear during assembly is carried out continuously by flow of pulverulent material through a calibrated nozzle, nozzle fixed at the end a flexible and adjustable pipe, this assembly being integral in movement with the arm of the forklift. 11) Method according to claim 10, characterized in that the mass flow rate of powdery refractory product, flowing from a tank located at the top of the vertical mast, is controlled by a necking device on this nozzle.