Protection device for electrode lifting mechanism of electric arc furnace

Abstract

The utility model discloses a protection device for an electric arc furnace electrode lifting mechanism, which is characterized in that a cross arm is connected with a water-cooled cable, the cross arm is fixed on a stand column water tank below the cross arm through a hanging screw rod, an insulation sleeve covers the hanging screw rod, a spraying ring is fixed on the cross arm, and spraying is realized at the position corresponding to the water-cooled cable; a protective cover is fixed on the outer side of the stand column water tank, and protection is achieved at the position corresponding to the insulating cover. According to the utility model, the electromagnetic valve automatic switch can be used to spray and cool the outermost water-cooled cable, so that the service life is prolonged; and a cross arm hanging screw insulating sleeve is protected, so that the arcing accident caused by damage to the insulating sleeve due to splashing of steel slag caused by relatively high moisture in waste steel during charging is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of metallurgical equipment, in particular to a protective device for an arc furnace electrode lifting mechanism. Background Art

[0002] Electric arc furnace steelmaking is also known as "electric furnace steelmaking method". It uses the lifting electrodes on the top of the electric arc furnace to form a discharge gap with the scrap steel in the furnace, generate an arc, convert electrical energy into heat energy, and heat and melt metal and slag to produce liquid steel with the help of radiation and the direct action of the arc. The side of the electric furnace steel outlet is called the back of the furnace, and the side of the furnace door is called the front of the furnace. There are 3 electrode lifting mechanisms on one side of the furnace body. Each electrode lifting mechanism is equipped with an electrode lifting column with a horizontal electrode cross arm, and the end is a water-cooled electrode clamp to clamp the electrode extending into the furnace. The function of the electrode lifting mechanism is to adjust the arc length in the furnace (change the power), respond promptly and quickly to accidental factors that affect the arc power in the furnace, and maintain the stability of the given arc power in each process stage. The furnace body is placed on the tilting furnace base at the bottom. The upper platform of the furnace base is the steelmaking operation platform. The furnace base is placed on a concrete foundation. The arc beam is meshed with the horizontal rail beam on the foundation. The tilting mechanism is operated by the oil cylinder to make the furnace body and the electrode lifting mechanism tilt as a whole to the back of the furnace to discharge steel or to the front of the furnace to discharge slag. A railway line is laid between the concrete foundations, and ladle cars and slag cars enter and exit along this line.

[0003] At present, the ultra-high power electric arc furnace has been put into operation since 1995. It adopts a furnace top large basket with scrap steel and molten iron automatically fed into the charge structure. Due to the use of retained steel and scrap steel operation, the open flame is relatively large when the large basket with a crane is used to add scrap steel. The entire charging time is maintained at 1.5 minutes. In this process, the water-cooled cable on the outermost cross arm is subjected to the baking of the open flame. Although the surface of the water-cooled cable rubber sheath is wrapped with asbestos cloth, the normal service life of the water-cooled cable is unstable, ranging from a few days to 2 months. If there is a lot of water in the scrap steel, it is very easy to cause slag splashing. Occasionally, slag will splash onto the cross arm tightening screw, adhere to the ground and arc, and the arcing column at the tightening screw will leak. The cross arm grounding at the leaking point cannot supply power for smelting.

[0004] To solve this kind of problem, the conventional method is to immediately stop the furnace and replace the water-cooling cable to avoid power supply overheating when there is a large cable leakage. If there is slag splashing and the column arcs and leaks, the power supply will be stopped immediately, the slag will be cleaned, the leaking column will be treated and the insulating parts will be replaced. When the electrode is at a high position, the no-load voltage on the secondary side will be detected until the three-phase voltage is stable before continuing production. Summary of the invention

[0005] Purpose of the utility model: In order to overcome the shortcomings of the background technology, the utility model seeks to protect a protective device for an arc furnace electrode lifting mechanism.

[0006] Technical solution: The arc furnace electrode lifting mechanism protection device disclosed by the utility model has a cross arm connected to a water-cooling cable, the cross arm is fixed to a column water tank below by a tightening screw, an insulating sleeve covers the tightening screw, a spray ring is fixed on the cross arm, spraying is achieved at the position corresponding to the water-cooling cable; a protective cover is fixed on the outside of the column water tank, protection is achieved at the position corresponding to the insulating cover.

[0007] Furthermore, the spray ring is placed at the cross arm at the upper end of the outermost water-cooling cable, and is an annular structure extending downward from the cross arm and circumferentially surrounding the water-cooling cable.

[0008] Furthermore, a plurality of spray ports are circumferentially spaced apart on the spray ring.

[0009] Furthermore, the spray ring is connected to a water pipe and is remotely controlled by a solenoid valve; the solenoid valve is connected to an output terminal of a state signal of the electric furnace.

[0010] Furthermore, the outer contour of the protective cover is consistent with the corresponding position of the column water tank.

[0011] Furthermore, the protective cover is provided with a positioning hole for hanging on the column water tank.

[0012] Beneficial effects: Compared with the prior art, the advantages of the utility model are: using the solenoid valve to automatically switch to spray cool the outermost water-cooled cable to increase its service life; protecting the insulating sleeve of the cross arm tightening screw to avoid slag splashing caused by the large amount of water in the scrap steel during feeding, which can damage the insulating sleeve and cause arcing accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0014] Figure 2 This is a top view of the spray ring of the utility model;

[0015] Figure 3 This is a top view of the protective cover of the utility model. Implementation

[0016] like Figure 1-3The arc furnace electrode lifting mechanism protection device shown in the figure has a horizontal arm 1 connected to a water-cooled cable 2, and the horizontal arm 1 is fixed to the column water tank 3 below by a tightening screw, and the tightening screw is covered by an insulating sleeve, which is characterized in that: a spray ring 4 is fixed on the horizontal arm 1, and spraying is achieved corresponding to the position of the water-cooled cable 2; the spray ring 4 is placed at the horizontal arm at the upper end of the outermost water-cooled cable 2, and is an annular structure extending downward from the horizontal arm and surrounding the water-cooled cable 2 circumferentially, and multiple spray ports are arranged at intervals in the circumference. The spray ring 4 is connected to a water pipe and remotely controlled by a solenoid valve; the solenoid valve is connected to the electric furnace status signal output end, and the valve is opened by interlocking with the electric furnace finished steel shaking lock signal in the preparation, spray cooling the water-cooled cable in advance, and resisting open flame baking when the furnace cover is unscrewed, thereby achieving the purpose of extending the life of the water-cooled cable.

[0017] A protective cover 5 is fixed on the outside of the column water tank 3 to provide protection for the position of the corresponding insulating cover. The outer contour of the protective cover 5 is consistent with the corresponding position of the column water tank 3 and is made according to the outer dimensions of the column water tank. The protective cover 5 is provided with a positioning hole 6 for hanging on the column water tank 3. After installation, the insulating sleeve of the cross arm tightening screw is protected to prevent slag splashing caused by the large amount of water in the scrap steel during feeding, which may damage the insulating sleeve and cause arcing accidents.

[0018] After the device was put into use, the service life of the water-cooling cable during the electric furnace smelting process was greatly improved (the service life was increased to 6 months) and the occurrence of arcing accidents was reduced (the electric furnace downtime was 100 minutes / year), reducing the electric furnace downtime caused by such accidents.

Claims

1. A protective device for an arc furnace electrode lifting mechanism, wherein a cross arm (1) is connected to a water-cooling cable (2), the cross arm (1) is fixed to a column water tank (3) below by a tightening screw, and an insulating sleeve covers the tightening screw, characterized in that: A spray ring (4) is fixed on the cross arm (1) to achieve spraying at a position corresponding to the water-cooling cable (2); a protective cover (5) is fixed on the outside of the column water tank (3) to achieve protection at a position corresponding to the insulating cover.

2. The arc furnace electrode lifting mechanism protection device according to claim 1, characterized in that: The spray ring (4) is placed at the cross arm at the upper end of the outermost water-cooling cable (2), and is an annular structure that extends downward from the cross arm and circumferentially surrounds the water-cooling cable (2).

3. The arc furnace electrode lifting mechanism protection device according to claim 2, characterized in that: The spray ring (4) is provided with a plurality of spray openings at intervals in the circumferential direction.

4. The arc furnace electrode lifting mechanism protection device according to claim 1, characterized in that: The spray ring (4) is connected to a water pipe and is remotely controlled via a solenoid valve; the solenoid valve is connected to an electric furnace status signal output terminal.

5. The arc furnace electrode lifting mechanism protection device according to claim 1, characterized in that: The outer contour of the protective cover (5) is consistent with the corresponding position of the column water tank (3).

6. The arc furnace electrode lifting mechanism protection device according to claim 1, characterized in that: The protective cover (5) is provided with a positioning hole (6) for being hung on the column water tank (3).

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