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RU-2861642-C2 - ELECTROSLAG REMELTING PLANT AND METHOD OF CONTROLLING ELECTROSLAG REMELTING PLANT

RU2861642C2RU 2861642 C2RU2861642 C2RU 2861642C2RU-2861642-C2

Abstract

FIELD: metallurgy. SUBSTANCE: invention relates to special electrometallurgy, particularly, to electroslag remelting furnaces. Installation comprises devices for balancing the weight of carriages with equipment fixed on them, a consumable electrode or a formed ingot and is equipped with drives of their vertical movement, which have a control system, according to the number of carriages. Each balancing device consists of two units, one of which is a movable unit and is suspended at the free end of said flexible link, and the second - the fixed unit is installed on the fixed support, as well as from the counterweight load, part of which is supported by the unit suspended on the free end of the flexible connection, and the other part of the load is supported by the fixed unit installed on the fixed support, at that, it is equipped with a control system of the weight ratio of the parts of the counterweight in the form of a part suspended on the free end of the said flexible connection, and a part resting on a fixed unit mounted on a fixed support, and between the carriage and the drive of its vertical movement, a dynamometric device mechanically connected to it is introduced, which measuring output is connected to the input of the counterweight weight ratio control system. In the method, the balancing force is controlled by changing the weight of the parts of the counterweight, the direction of the vertical force acting on the drive for moving the carriage is kept constant, and the value of said force is kept in the specified range, at remelting of the consumable electrode, the speed of the displacement drive of at least one carriage is controlled and maintained in the specified range. EFFECT: ensuring smoothness and accuracy of electrode and tray movement, as well as high reliability of the installation and safety of its operation. 8 cl, 5 dwg

Inventors

  • NEKHAMIN SERGEJ MARKOVICH
  • Orlovskij Evgenij Genrikhovich

Dates

Publication Date
20260506
Application Date
20240109

Claims (8)

  1. 1. An electroslag remelting plant comprising process equipment for a consumable electrode and an ingot being formed, at least one carriage with process equipment secured thereto, configured to move along a vertical column guide containing fixed blocks in the upper part, through which a flexible connection connected at one end to the carriage is thrown, connected at its free end to devices made according to the number of carriages for balancing the weight of the carriages with the equipment, consumable electrode or ingot being formed secured thereto, wherein the plant is equipped according to the number of carriages with drives for their vertical movement, having a control system, characterized in that each balancing device consists of two units, one of which is a movable unit and is suspended at the free end of the said flexible connection, and the second is a fixed unit mounted on a fixed support, as well as from a counterweight load, part of which is supported on a unit suspended at the free end of the flexible connection, and the other part the load is supported on a fixed unit mounted on a fixed support, and is equipped with a control system for the ratio of the masses of the parts of the counterweight load in the form of a part suspended on the free end of the said flexible connection and a part resting on a fixed unit mounted on a fixed support, and between the carriage and the drive for its vertical movement a dynamometric device is introduced, mechanically connected to it, the measuring output of which is connected to the input of the control system for the ratio of the masses of the parts of the counterweight load.
  2. 2. The installation according to paragraph 1, characterized in that one carriage is located below the other, wherein the technological equipment in the form of a consumable electrode head is secured on one carriage by means of an electrode holder, and on the other carriage, located below the first, the technological equipment for the formed ingot is secured by means of a bracket, made in the form of a pallet on which the ingot is formed.
  3. 3. The installation according to paragraph 2, characterized in that the fixed units of the balancing system of the upper and lower carriages are combined into a single structure, in which the movable unit of the device for balancing the weight of the upper carriage is located above the movable unit of the device for balancing the weight of the lower carriage, between the upper and lower mentioned movable units, as well as between the lower mentioned movable unit and the fixed unit of the device for balancing the weight of the carriages, channels for moving a part of the counterweight load are made, including a device for regulating the intensity of movement of the load.
  4. 4. The installation according to paragraph 1, characterized in that the said movable and fixed units are made in the form of containers, and the parts of the counterweight load are bulk material or dispersed material.
  5. 5. The installation according to paragraph 1, characterized in that the said movable and fixed units are made in the form of containers, and parts of the counterweight load are liquid.
  6. 6. A method for controlling an electroslag remelting installation, in which, during the remelting of a consumable electrode, the installation is controlled according to paragraph 1, wherein at least one carriage is moved vertically, on which the consumable electrode is secured by means of an electrode holder, a vertical force acting on the drive for moving at least one carriage is determined, and at least one carriage is affected by a balancing force of the mass of parts of the counterweight load, characterized in that the balancing force is adjusted by changing the mass of parts of the counterweight load, the direction of the vertical force acting on the drive for moving the carriage is maintained constant, and the magnitude of said force is maintained in a given range, during the remelting of the consumable electrode, the speed of the drive for moving at least one carriage is monitored and maintained in a given range.
  7. 7. The method according to item 6, in which a pallet with an ingot being formed is secured to the second carriage.
  8. 8. The method according to claim 6, in which, when the speed of the drive for moving at least one carriage of a given range increases, the balancing force is changed by changing the masses of the parts of the counterweight load until the movement of the carriage stops, and when the speed of the drive for moving at least one carriage decreases to an acceptable limit, the operation of the drive for moving at least one carriage is blocked.

Description

The claimed inventions relate to special electrometallurgy and can be used in installations for electroslag smelting of solid and hollow ingots or blanks. An electroslag remelting (ESR) installation is known, containing a column with carriages for moving the crystallizer and electrodes mounted on it, having individual drives in the form of hydraulic cylinders and balanced by means of a counterweight, wherein the hydraulic cylinders are connected to the carriage housings, and the rods are pivotally fixed on the column [USSR A.s. 505310, C21C 5/56, issue dated 22.04.1974]. A disadvantage of this device is that when smelting large ingots and blanks, due to the long carriage strokes exceeding 10 or even 20 meters, it is technically and economically impossible to manufacture hydraulic cylinders with the specified stroke. Furthermore, in the event of an oil leak, the hydraulic drive does not provide self-braking of the carriages, which could lead to a serious accident. This technical solution also has a drawback related to the installation layout. To reduce the bending moment acting on the column and carriages, it is advisable to position the hydraulic cylinders between the column on one side and the electrode with the mold on the other. However, placing hydraulic cylinders in this zone of the ESR, which is subject to strong thermal radiation and possible accidental slag releases, poses an increased fire hazard. A furnace for electroslag remelting is known, comprising a column, a carriage with a drive for vertical movement along a toothed rack secured to the column, an electromagnet, a vertical spring-loaded rod with a wedge, an accelerating gearbox, a gear mounted on the carriage, a generator electrically connected to the electromagnet, the rod of which has a bevel that engages with a bevel on the vertical spring-loaded rod with a wedge located under a roller, wherein the gearbox is connected to the accelerating gearbox, the output shaft of which is connected to the generator [USSR A.S. 615689, C21C 5/56, issue dated 02/08/1977]. The use of a rack and pinion drive in this technical solution predetermines its drawbacks. The inherent backlash of a rack and pinion drive prevents the required smoothness and precision of carriage movement in operational situations where the direction of carriage movement or the direction of forces acting upon it changes. This is particularly true for the mold carriage when melting hollow blanks using a counter-movement system with the electrode and mold/mandrel. Due to the sharply varying forces exerted on the mandrel during shrinkage of the hollow blank, backlash in the rack and pinion drive results in jerky movement of the mold/mandrel, which poses the risk of slag breaking through the gap between the blank and the mold. Another significant drawback of the rack and pinion drive is the lack of self-braking of the carriages, which, in the event of a drive link failure, leads to an emergency fall of the carriage. To prevent such an accident, special structural elements are incorporated into this device. As a result, the design of the ESR furnace becomes significantly more complex, reducing its reliability. In addition, the emergency braking measures of the carriages under consideration are active and are triggered only when the accident has already significantly developed, as a result of which they are not sufficiently reliable. A method for controlling an electroslag remelting unit is known, in which, during the electroslag remelting process, the actual weight of the electrode is measured and compared with the specified weight, and based on their difference, a corresponding signal is sent to the control body [German Patent 1934218, C21C 5/52, issued on July 5, 1969]. A drawback of this technical solution is that it does not address the problem of column curvature changes during the remelting process under the variable cantilever load caused by the widely varying weight of the consumable electrode. When smelting large ingots by remelting a single electrode, the mass of which can vary from 100 tons or more to zero during the remelting process, the changing column curvature causes the electrode to shift relative to the crystallizer axis, resulting in deterioration in the quality of the smelted ingot. An electroslag remelting installation is known, containing technological equipment, at least one carriage with the technological equipment fixed to it, placed with the possibility of movement on a column guide, on the upper part of which fixed blocks are fixed, through which a flexible connection connected to the carriage is thrown, passing through movable blocks connected to a balancing device in the form of a counterweight [USSR A.s. 473430, C21C 5/56, dated 22.04.1974]. The disadvantage of this device is that it largely retains the shortcomings of the previous technical solution, as the counterweight can only balance the weight of the carriage and the crystallizer. The weight of the cons