CN216263380U

CN216263380U - Device for electromagnetically conveying cold steel

Info

Publication number: CN216263380U
Application number: CN202120984475.4U
Authority: CN
Inventors: 宁哲; 曾红波; 艾新港; 李胜利; 刘海啸; 窦莹莹
Original assignee: University of Science and Technology Liaoning USTL
Current assignee: University of Science and Technology Liaoning USTL
Priority date: 2021-05-10
Filing date: 2021-05-10
Publication date: 2022-04-12
Anticipated expiration: 2031-05-10

Abstract

The utility model belongs to the technical field of continuous casting in ferrous metallurgy industry, and particularly relates to a device for electromagnetically conveying cold steel, which is characterized by comprising an insulating guide groove, a coil, a feeding funnel, a power supply, a PLC (programmable logic controller) and a gas protection system, wherein an opening at one end of the insulating guide groove is connected with the feeding funnel, an opening at the other end of the insulating guide groove is communicated with the side wall of a water outlet arranged between a tundish and a crystallizer through a connecting fastener, the coil is wound on the insulating guide groove, and two ends of the coil are respectively connected with the power supply and the PLC; the gas protection system comprises a protective gas tank, a gas pipeline and a regulating valve on the gas pipeline, and the gas pipeline is communicated with the insulating guide groove. The utility model has the advantages that: 1) cold steel can be added by utilizing the original water gap, and the method has good adaptability to the plate blank or square billet with smaller casting size; 2) the problem of air holes in the steel billet is solved. 3) The speed of adding cold steel into the crystallizer can be controlled; 4) the device has simple structure and low operation and maintenance cost.

Description

Device for electromagnetically conveying cold steel

Technical Field

The utility model relates to the technical field of continuous casting in the ferrous metallurgy industry, in particular to a device for electromagnetically conveying cold steel.

Background

In recent years, continuous casting technology has been greatly improved, and internal quality defects such as billet center segregation and porosity are gradually highlighted along with the continuous improvement of the drawing speed. The method is an effective means for eliminating center segregation and improving the internal quality of the billet. The continuous casting crystallizer steel strip feeding technology inserts a steel strip into a crystallizer, changes the distribution of a temperature field in the crystallizer, melts and absorbs heat in the crystallizer by the steel strip, reduces the superheat degree of molten steel and the temperature gradient of the section of a casting blank, ensures that the temperature distribution is more favorable for the implementation of an isometric crystal crystallization process, and is favorable for improving the nucleation rate of the casting blank, thereby improving the quality of the continuous casting blank, optimizing the solidification structure of the casting blank, and having good application prospect in industry. In China, some enterprises have already finished the experimental work of steel strip feeding process equipment of a continuous casting crystallizer, but the liquid level of the crystallizer can fluctuate in the steel strip feeding process, the problems of slag entrapment and the like occur, the quality of continuous casting billets is seriously influenced, and the industrial mass production cannot be realized.

Patent publication No. CN102974791A discloses a steel strip feeding system for a continuous casting mold, in which a steel strip is fed into an electromagnetic vibrator from a guide pipe and then into the mold, and the electromagnetic vibrator by means of an electromagnet imparts forced resonance to the steel strip when the steel strip is fed into the mold. However, the electromagnetic vibration guide pipe can disturb the crystallizer protective slag layer to generate slag entrapment, and the inserted guide pipe can be corroded and damaged in high-temperature molten steel to pollute the molten steel. Patent publication No. CN107900298A discloses a crystallizer belt feeding device for producing high-quality continuous casting slabs; the steel strip penetrates into the feeding strip guide groove to be fed to the thickness center of the crystallizer, the defects are that the structure is complex, the cost is increased, and meanwhile, the problem that casting blank quality is influenced because protective slag on the surface of molten steel is brought into the molten steel when cold steel enters the crystallizer exists. Patent publication No. CN206065356U discloses a protection device for a variable slag line for feeding strip steel to a continuous casting crystallizer and the continuous casting crystallizer, wherein the protection slag is discharged through the protection device and then a cold steel strip is vertically added into a protection pipe. The defect is that the exposed molten steel can be oxidized to influence the quality of casting blanks.

Therefore, in the existing strip feeding technology, one type is to directly add cold steel strips into a crystallizer through a steel feeding device, and the technology can cause casting powder to be involved into a casting blank to influence the quality of the casting blank in the steel feeding process; the other type is that a slag discharging device, such as a slag discharging baffle plate, a slag discharging cover and the like, is adopted, the device occupies a large space at the upper part of a crystallizer, brings inconvenience to production operation, is complex, increases later maintenance cost, and in long-term work, refractory materials on the slag avoiding device soaked in molten steel can fall into the molten steel to influence the quality of a casting blank, and meanwhile, the exposed molten steel can be oxidized to influence the quality of the casting blank; the last type is that the slag adhesion phenomenon is reduced through an electromagnetic vibration mode, but the vibration steel feeding of the type has great influence on the fluctuation of the steel liquid level, the slag rolling phenomenon is serious, and the quality of the casting blank is still reduced.

Disclosure of Invention

The utility model aims to provide a device for electromagnetically conveying cold steel, which overcomes the defects of the prior art, conveys the cold steel to a water gap by electromagnetic force to add the cold steel, reduces the requirement on the upper space of a crystallizer, can adapt to almost all types of crystallizers, can solve the problems of slag entrapment and the like of cold steel feeding of the continuous casting crystallizer, improves the nucleation rate of casting blanks inside casting blanks or steel ingots, optimizes the solidification structure of the casting blanks or the steel ingots, and improves the quality of the continuous casting blanks.

In order to achieve the purpose, the utility model adopts the following technical scheme:

the device for electromagnetically conveying cold steel is characterized by comprising an insulating guide groove, a coil, a feeding funnel, a power supply, a PLC (programmable logic controller) and a gas protection system, wherein an opening at one end of the insulating guide groove is connected with the feeding funnel, an opening at the other end of the insulating guide groove is communicated with the side wall of a water outlet arranged between a tundish and a crystallizer through a connecting fastener, the coil is wound on the insulating guide groove, and two ends of the coil are respectively connected with the power supply and the PLC; the gas protection system comprises a protective gas tank, a gas pipeline and a regulating valve on the gas pipeline, and the gas pipeline is communicated with the insulating guide groove.

Further, connect the fastener structure and include mount pad, sealing washer, guide slot joint and spiral buckle, the mount pad is inlayed in the lateral wall of the resistant material of mouth of a river down, and the guide slot connects and matches for the other end external diameter of steel and insulating guide slot, and the external screw thread on spiral buckle and the mount pad meshes mutually.

Further, the sealing ring is a graphite sealing ring.

Further, the axis that the guide slot connects has an contained angle of tilt up 5~30 degrees, and its cooperation section with the other end of insulating guide slot is no less than 50 mm.

The connecting fastener provided by the utility model can be used as a substitute of the whole or a section of the lower nozzle to protect the nozzle from being damaged, the electromagnetic conveying device is filled with protective gas to balance the internal and external air pressure of the electromagnetic conveying device, so that molten steel is prevented from flowing back, and the cold steel is subjected to the action of Lorentz force to be sent out to enter the lower nozzle of the tundish and enter the crystallizer in compliance with the flowing of the molten steel.

Compared with the cold steel blown by carrier gas, the cold steel is added by electromagnetic force, so that the problem of air holes in the steel billet is solved; in addition, the device does not contact with high-temperature molten steel in the whole working process, thereby avoiding hot corrosion and molten steel scouring of the device and being beneficial to prolonging the service life of the electromagnetic device.

Compared with the prior art, the utility model has the beneficial effects that:

1) cold steel can be added only by utilizing the original water gap, the upper space of the crystallizer is enlarged, and the method has good adaptability to casting plate blanks or square blanks with smaller sizes;

2) the utility model provides a new cold steel adding method, namely a method for adding cold steel into a pouring box water outlet to enter a crystallizer, so that the cold steel is prevented from being involved in casting powder while being added;

3) the cold steel is added by electromagnetic force through the internal and external air pressure of the protective gas balance electromagnetic conveying device, and compared with the method of blowing the cold steel by carrier gas, the problem of air holes in the steel billet is solved.

4) The speed of adding cold steel into the crystallizer can be controlled according to actual process parameters and requirements thereof;

5) the electromagnetic conveying device is not contacted with the high-temperature molten steel flowing out of the tundish, so that the hot corrosion of the device and the scouring of the molten steel are avoided, and the service life of the electromagnetic conveying device is prolonged;

6) the connecting fastener can be used as a substitute for the whole or a section of the lower nozzle to protect the nozzle from being damaged, so that the damage resistance of the existing nozzle is improved;

7) the device has the advantages of simple structure, low operation and maintenance cost and wide universality.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment of an electromagnetic cold steel conveying device of the utility model;

FIG. 2 is a schematic structural diagram of an embodiment of the method for electromagnetically conveying cold steel according to the utility model, which shows the state of adding cold steel;

fig. 3 is a schematic view of a connecting fastener according to an embodiment of the present invention.

In the figure: 1-molten steel, 2-tundish, 3-electromagnetic conveying device, 4-cold steel, 5-crystallizer, 6-water outlet, 7-tundish temperature measuring device, 8-insulating guide groove, 9-coil (multiple groups), 10-feeding hopper, 11-connecting fastener, 12-power supply, 13-PLC controller, 14-exhaust valve, 15-air inlet valve, 16-exhaust pump, 17-pressure controller, 18-gas flowmeter, 19-protective gas tank, 21-water outlet refractory, 22-mounting seat, 23-guide groove joint, 24-sealing ring and 25-spiral buckle.

Detailed Description

The technical solution of the present invention is further illustrated by the following examples:

in the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Referring to fig. 1-3, which are schematic structural views of an embodiment of an electromagnetic cold steel conveying device of the present invention, the electromagnetic cold steel conveying device includes an insulating guide slot 8, a coil 9, a feeding funnel 10, a power supply 12, a PLC controller 13, and a gas protection system, wherein an opening at one end of the insulating guide slot 8 is connected to the feeding funnel 10, an opening at the other end is communicated with a drain 6 arranged between a tundish 2 and a crystallizer 5 through a connecting fastener 11, the coil 9 is wound on the insulating guide slot 8, and two ends of the coil 9 are respectively connected to the power supply 12 and the PLC controller 13; 16. an exhaust line and a control valve on the line; the gas protection system comprises a protective gas tank 19, a gas pipeline and a regulating valve on the gas pipeline, and the gas pipeline are communicated with the insulating guide groove 8.

Connect fastener structure and include mount pad 22, sealing washer 24, guide slot joint 23 and spiral buckle 25, mount pad 22 inlays in the lateral wall of lower mouth of a river resistant material 21, and guide slot joint 23 matches for steel and the other end external diameter of insulating guide slot 8, and spiral buckle 25 meshes with the external screw thread on the mount pad 22 mutually. The seal ring 24 is a graphite seal ring. The axis of the guide groove joint 23 is provided with an included angle which inclines upwards by 5-30 degrees, and the included angle is not less than 50mm with the matching section of the other end of the insulating guide groove 8, so that the moving resistance of cold steel is reduced.

The utility model creatively provides the idea of adding cold steel at the water gap of the tundish, which is completely different from the traditional method, other cold steel adding devices are not designed on the liquid level of the crystallizer steel, and the design and installation are only needed to be carried out at the middle part of the original water gap, so that a large area of operable space is saved for the liquid level of the crystallizer; the utility model avoids the direct contact of the device with the molten steel and prolongs the service life of the cold steel conveying device. The utility model can simply and quickly control the adding speed of cold steel through actual casting parameters and can continuously add the cold steel; the utility model can avoid the backflow of the molten steel in a mode of balancing air pressure. In the continuous casting process, in order to prevent the molten steel from flowing backwards into the electromagnetic conveying device in the casting process and damaging the electromagnetic conveying device and polluting the molten steel, a set of gas shield system is arranged and designed outside the insulated guide groove, so that the negative pressure caused by the downstream flow of the molten steel in the casting process can be balanced, the backflow of the molten steel is avoided, and the cold steel conveying device is independent from the outer side of the water gap and does not influence the molten steel.

The insulating guide groove designed by the utility model is mainly made of calcium carbonate material, and the connecting fastener 11 ensures that the electromagnetic conveying device is stably connected with the tundish sewer opening, so that the two refractory materials can be prevented from being extruded and damaged. The sealing ring 24 is fixed by a spiral buckle 25, so that the drain 6 is stably connected with the electromagnetic conveying device 3. Before casting, firstly filling cold steel 4 in a feeding funnel 10, then closing an upper opening of the funnel to seal a cold steel conveying device, then opening an exhaust valve 14, opening an exhaust pump 16 through a pressure controller 17 to exhaust air in an electromagnetic conveying device, closing the exhaust valve 14 after exhausting, then opening an air inlet valve 15, opening a gas flowmeter 18 through the pressure controller 17, adding argon in an argon gas storage tank 19 into the electromagnetic conveying device 3 to balance air pressure, at the moment, the electromagnetic conveying device enters a working state, detecting the temperature in a tundish through a tundish temperature measuring device 7 and returning the temperature to a PLC 13, controlling the current in a coil 9 through the PLC 13, moving the cold steel 4 to a tundish water outlet 6 under the action of the force generated by the coil 9 in a magnetic field, and enabling the cold steel to flow into a crystallizer in compliance with the molten steel. The entering of cold steel changes the distribution of a temperature field in the crystallizer, the cold steel is solidified and then melted in the crystallizer, the superheat degree of molten steel and the temperature gradient of the section of a casting blank are reduced, the temperature distribution is more favorable for the implementation of an isometric crystal crystallization process, and the nucleation rate of the casting blank is favorably improved.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical scope of the present invention and the equivalent alternatives or modifications according to the technical solution of the present invention and the inventive concept thereof.

Claims

1. The device for electromagnetically conveying cold steel is characterized by comprising an insulating guide groove, a coil, a feeding funnel, a power supply, a PLC (programmable logic controller) and a gas protection system, wherein an opening at one end of the insulating guide groove is connected with the feeding funnel, an opening at the other end of the insulating guide groove is communicated with the side wall of a water outlet arranged between a tundish and a crystallizer through a connecting fastener, the coil is wound on the insulating guide groove, and two ends of the coil are respectively connected with the power supply and the PLC; the gas protection system comprises a protective gas tank, a gas pipeline and a regulating valve on the gas pipeline, and the gas pipeline is communicated with the insulating guide groove.

2. The apparatus of claim 1, wherein the connecting fastener structure comprises a mounting seat, a sealing ring, a guide groove joint and a spiral buckle, the mounting seat is embedded in the side wall of the drain nozzle refractory, the guide groove joint is made of steel and matched with the outer diameter of the other end of the insulating guide groove, and the spiral buckle is meshed with the external thread on the mounting seat.

3. An electromagnetic cold steel conveying apparatus according to claim 2, wherein the sealing ring is a graphite sealing ring.

4. The device for electromagnetically conveying cold steel according to claim 2, wherein the central axis of the joint of the guide groove has an included angle of 5 to 30 degrees inclined upward, and the length of the central axis of the joint of the guide groove is not less than 50mm from the matching section of the other end of the insulating guide groove.