Patent Application
20080058981
The invention relates to a continuous casting installation with at least one robot for carrying out process-controlled or automated interventions on the continuous casting installation and accessing assigned auxiliary devices. Furthermore, the invention relates to a method for operating a continuous casting installation including a robot.
The present invention extends to all types of continuous casting installations in which molten metal from a molten metal container, such as for example a casting ladle, is directed via a tundish into a chilled mould, shaped there under intensive cooling to form an at least partly solidified strand of any desired cross section and continuously conveyed out of the continuous casting installation. According to the characteristics of the moulds that are used, the casting installations may be equipped with oscillating tubular and plate moulds, track moulds, rotating casting rolls with side plates (two-roll casting installations) or moulds with circulating belts. The strands may have cross sections of slabs, thin slabs, strips, blooms or billets and any other desired preliminary shaping cross sections of any desired dimensions.
Robots are used on a continuous casting installation for carrying out recurrent work and to eliminate operating problems in hazardous areas in which the operating personnel are subjected to great heat exposure, emanating from the liquid metal and the cast metal strand, or spattered slag and metal. Robots are already used at the open continuous casting mould to observe the surface of the molten bath, to eliminate deposits baked on the inner sides of the mould walls, to feed in casting powder, to measure temperatures and take samples and the like. Furthermore, robots are used for changing the shroud, changing the casting tube and for changing closure plates of the side gate nozzle and for blowing open the outflow opening at tundishes and casting ladles. Furthermore, it is known to use robots for inspecting the cast strands or the cut-off slabs, blooms and billets and for the elimination of defects, for example by flaming, in the outlet region of a continuous casting installation.
For example, the use of a multifunctional robot on a continuous casting mould is already known from EP-B 371 482, the robot on the one hand receiving data relating to the casting process from measuring devices on the mould and on the other hand acquiring measuring data itself on the mould by a detection system, for example an optical detection system, and using this information to prepare and implement a plan of action with priority assignment. A stationary robot is concerned here, the location of which is chosen specifically for use on the mould and is accordingly not suitable for performing activities likewise occurring in areas of the continuous casting installation neighbouring the continuous casting mould.
Robots which are likewise assigned to a single working area at a continuous casting installation are known from U.S. Pat. No. 5,067,553, JP-A 5-169206, JP-A 9-109100, JP-A 7-60434 and JP-A-293615.
More extensive use of robot technology on the casting platform of a continuous casting installation previously led to a massing of such robots and to confused operations proceeding in confined spaces. JP-A 3-71959 discloses the use of two robots on a casting platform of a multistrand continuous casting installation, each robot being assigned a runway and the robot being able to assume an operating position on this runway to exchange casting tubes on a large tundish and carry out cleaning work at the outlet openings of the tundish and the casting tubes. Each robot is assigned a demarcated working area, it not being possible for one robot to work in the working area of another robot, so that if one robot fails the other robot cannot take over this work and interventions on the continuous casting installation by the operating personnel are necessary. Altogether, the proliferation of robots increases the investment costs and operating costs, without at the same time achieving improved availability of the individual robot.
The object of the present invention is therefore to avoid these disadvantages and difficulties of the known prior art and to propose a continuous casting installation with at least one robot of the type described at the beginning and a method for operating a continuous casting installation including a robot, with which different interventions on a continuous casting installation can be carried out at various working positions which lie outside the range of a single operating position of a robot.
A further aim of the invention is to increase the degree of utilization and the availability of the robot or robots used.
This object is achieved according to the invention by the continuous casting installation being assigned a runway, by the robot being assigned a travelling mechanism and the travelling mechanism being displaceably guided on the runway, by at least one parking position and at least two operating positions being defined for the robot on the runway and each operating position being assigned working areas on the continuous casting installation that can only be reached from this operating position, by the distance between each operating position of the robot and the assigned operating area or supply area being fixed within the minimum and maximum range of the robot arm and by the robot being equipped with a data transmitting and receiving device and the latter being connected by signalling technology to a central control device or a process computer of the continuous casting installation.
The fixing of a runway on the continuous casting installation, or in zones of a continuous casting installation, which is taken past a number of potential working areas in such a way that these working areas lie within the range of predetermined operating positions of a robot which can be made to move on the runway has the effect of overcoming the restricted, only single operating capability of the robot and creating a much more efficient operating capability. Depending on demand, the robot can be guided by a central control device or the process computer of the continuous casting installation to each desired operating position and carry out the interventions necessary there.
Operating positions for the robot define locations of the robot along the runway from which one or more working areas on the continuous casting installation lie within the range of the robot gripper. In embodiments of the robot in which the robot stand is secured on the travelling mechanism fixedly or rotatably about a vertical axis, the operating positions of the robot on the runway are defined by the position of the travelling mechanism alone. In the case of embodiments of the robot in which a swiveling mechanism with a jib is arranged on the travelling mechanism, and the actual robot is only fastened on the projecting end of the jib, the swiveling angle of the jib of the swiveling mechanism is also decisive in addition to the position of the travelling mechanism for defining the operating position of the robot.
Working areas of the robot are special areas or individual locations on the continuous casting installation where interventions are performed by the robot, starting from a predetermined operating position.
Supply areas comprise, in spatial terms, storage places with auxiliary devices, such as tool stores, utility stores and similar devices, which have fixed positions for tools, spare parts and utilities to be received and deposited by the robot. Stored in the auxiliary devices are firstly tools for the robot that are required for carrying out the interventions, such as for example tongs, measuring probes, grinding heads, secondly spare parts for the continuous casting installation, such as casting tubes or slide valve plates, and thirdly utilities for the continuous operation of the continuous casting installation, such as for example casting powder. The tool stores and utility stores provided in the respective supply areas may be formed by stationary or mobile auxiliary devices, the mobile auxiliary devices, for example a utilities carriage, possibly only being brought into the supply area of a specific operating position when required, and stocked up away from its supplying position.
The parking position is defined as the position of the robot on the runway at which it stops when it is carrying out interventions and waits for a new operating signal from the central control device or the process computer. When a number of robots are assigned to one runway, a number of parking positions are accordingly defined. In the case of two robots, the two parking positions are preferably arranged at opposite ends of the runway.
The carrying out of process-controlled or automated interventions by the robot also comprises the alternative possibility of an intervention that is manually remote-controlled by the operating personnel. These manually remote-controlled interventions can take place from the control room or by means of other portable control units.
The runway for the robot is preferably formed by a track system or by at least one running rail in the manner of an overhead monorail conveyor or craneway. Moving to predetermined operating positions is achieved by corresponding control devices (position transmitters, displacement monitoring systems).
To be able to serve a multiplicity of working areas on the continuous casting installation, it is expedient if the runway has branches with the inclusion of customary points. This allows operating positions away from a main runway to be defined and assumed and a number of robots can be used without them hindering one another.
Alternatively, individual sections of the runway are formed in such a way that they can be adjusted in height by means of lifting mechanisms or can be swiveled by swiveling mechanisms, in order to change the operating position of the robot on the runway in such a way that best-possible access to the assigned operating area is achieved.
Each robot is assigned a travelling mechanism, on which it is supported or suspended, depending on the design of the runway. To increase the size of its operating area, the travelling mechanism may be assigned a robot swiveling mechanism, whereby at least two operating positions are defined for the robot with the swiveling position of the robot swiveling mechanism. The swiveling mechanism preferably comprises an extending jib, on the extending end of which the robot is arranged. The jib may be adapted to requirements of the operating environment, possibly for example also made adjustable in height.
The robot is preferably fixed in its respective operating position by an arresting device, to avoid positional changes caused by reaction forces from the interventions.
To be able to carry out interventions on the continuous casting installation as quickly and efficiently as possible, it is expedient if each operating position of the robot on the runway is assigned at least one operating area at the continuous casting installation and a supply area at an auxiliary device, such as for example a tool store or a utilities store.
Consequently, all the utilities necessary for carrying out an intervention are available for the robot within the range of its robot arm, without it having to perform additional manipulating movements to change the tool or transport the spare part.
The runway may extend along the entire continuous casting installation and at different heights and may also comprise upward and downward slopes, preferably when the runway is formed as a running rail of an overhead conveyor. The runway is preferably restricted to the casting platform and/or to the delivery area of the continuous casting installation. Here, the runways are preferably arranged in a horizontal plane.
According to a preferred refinement, two robots are arranged on one runway, one robot preferably performing the interventions on the continuous casting installation as the primary robot and the second robot being used as an auxiliary robot when there are conflicts of priority for the work to be carried out and when there are problems with the primary robot. A different distribution between the robots of the work to be carried out, for example by priority assignment of individual robots to specific operating positions or assignment by manual remote control is quite possible, and is within the scope of the invention.
The invention also comprises a method for operating a continuous casting installation including at least one robot which can be displaced on a runway between a parking position and at least two operating positions and is characterized in that control signals are issued from a process computer or a central control device to the robot and, on the basis of these control signals, a selected operating position is moved to and automated interventions on the continuous casting installation are performed by the robot, the control signals for the interventions to be carried out on the continuous casting installation being issued by the process computer or a central control device to the robot in the sequence of the priority of the interventions to be carried out.
The operation of the robot is defined and controlled by the process computer of the continuous casting installation or a central control device, the activities to be carried out being determined with regard to the quality of the products to be produced. The basis for the priority assignment is formed by a continuous diagnosis of the casting process, consequently the continuously gathered measurement data and model calculations in comparison with default data.
The robot itself also carries out on the continues casting installation observations of the state of the casting process as it proceeds and gathers measurement data. These measurement data are transmitted to the process computer or a central control device, are processed by the process computer or the control device and results of this data evaluation are converted into control signals for the robot or the continuous casting installation.
When at least two robots which can be made to move on a runway are used, a first robot which can be made to move on the runway, as the primary robot (master robot), receives all the control signals and carries out interventions on the continuous casting installation and a further robot which can be made to move on the runway, as the auxiliary robot (slave robot), is preferably assigned to a parking position.
If there is a conflict of priorities of control signals, the primary robot and the auxiliary robot are activated and both robots are directed to the respective operating positions while excluding the possibility of them hindering one another.
Further advantages and features of the present invention emerge from the following description of non-restrictive exemplary embodiments, reference being made to the accompanying figures, in which:
On the casting platform 1 of a continuous casting installation, the layout of which is in no way restricted, the outlines are shown of a casting ladle 2 with a ladle nozzle 3 (shroud) and a tundish 4 positioned under it, with a submerged casting tube 5, which protrudes into a continuous casting mould 6. A further tundish 4′ is indicated by dashed-dotted lines in a standby position on the casting platform 1.
On this casting platform there are a wide variety of possibilities for having a robot carry out process-controlled and automated interventions on the casting installation, for which either the operation of a number of stationary robots or the operation of at least one mobile robot is necessary. A runway 7 is laid over the casting platform 1 in such a way that a multiplicity of working areas A1, A2, A3, A4 can be served by a single robot 8, starting from a number of operating positions E1, E2, E3 along the runway. The robot 8 is located in a waiting position in the parking position P1 at one end of the runway 7. A further parking position P2, which can likewise be used, is located at the opposite end of the runway 7. Supply areas V1, V2, V3 are provided at auxiliary devices H1, H2, H3 on the casting platform and these are assigned to operating positions E1, E2, E3 and are set up within the range of the robot arm 15. If the space conditions on the casting platform do not allow this, individual supply areas may also be set up outside the range of operating positions of the robot. The operating time of the robot for the completion of an intervention is then extended however by the period of time taken for necessary supplying movements.
From the operating position E1, the robot 8 can carry out interventions in the working areas A1 (casting ladle) and A4 (tundish) which relate to the ladle nozzle 3 and the shroud, and also the pouring-in area of the tundish 4. Among the activities to be carried out at time intervals in these working areas are, for example, changing of the shroud, burning clear the ladle nozzle or feeding the casting powder into the tundish. The spare parts and utilities necessary for these interventions, such as for example a replacement shroud, the necessary specific casting powder of the predetermined quality and amount or a burner, are taken by the robot from the assigned supply area V1, where these utilities are kept readily available in stock at predetermined places of the store of the auxiliary device H1.
Starting from the operating position E2, the robot 8 can carry out interventions in the operating areas A2 (mould) and A4 (tundish) which relate to the pouring-out area of the tundish 4, the submerged casting tube 5 and the opening on the inlet side of the continuous casting mould 6. Among the activities in these working areas are for example feeding casting powder into the tundish, changing of the submerged casting tube, burning clear the tundish outlet opening, feeding casting powder into the mould, observing the level of the bath in the mould, taking samples from the mould, etc. The utilities and spare parts necessary for these interventions, such as for example a casting powder appropriate for the quality of steel to be cast and the casting conditions at the given time, submerged casting tubes, sublances etc, are taken by the robot from the auxiliary device H2 in the supply area V2.
Starting from the operating position E3, the robot 8 can perform interventions on a further tundish 4′ in the working area A3 (tundish changing stand), taking the required utilities from the auxiliary device H3 in the supply area V3.
The parking position P2 is available to the robot as a second parking position if only one robot is provided on the casting platform. Alternatively, a further robot 8′ may wait at the parking position P2 to perform operations, whereby a much more efficient plan of action can be realized. If, for example, interventions of equal priority, neither of which can be delayed, must be carried out both in the working area A1 and in the working area A2, the control system or the process computer will direct the robot 8 from its parking position P1 to the operating position E1 and the robot 8′ from its parking position P2 to the operating position E2 assigned to it.
On the casting platform 1 there is the control stand 18, from which the continuous casting installation is monitored and operated in a largely automated manner by a process computer or a central control device. The process computer 19 or the central control device and also the individual robot or number of robots are assigned data transmitting and data receiving devices 20, 21, via which all the information necessary for carrying out the interventions are transmitted, preferably on a radio link.
In order to bring the robot into favourable operating positions, various special designs of the runway are possible.
In addition, branches can be used on the runway, using conventional points known from the railways. Upward sloping sections and downward sloping sections may be provided on the runway, it being possible for example to use cogwheel mechanisms to overcome upward and downward slopes.
The invention is not restricted to the use of particular types of robot. Particularly suitable for use on the casting platform of a continuous casting installation are buckling-arm robots or portable robots, as are universally offered by many manufacturers for the widest variety of operating possibilities and with special adaptations.
| Number | Date | Country | Kind |
|---|---|---|---|
| A 911/2004 | May 2004 | AT | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP05/04569 | 4/28/2005 | WO | 9/6/2007 |
