CN201353635Y - Extra Large Section Round Billet Continuous Casting Machine - Google Patents

Abstract

The utility model discloses a round billet conticaster with an extra large section (diameter phi 800mm to 1000mm), which is characterized in that the conticaster consists of the crystallizer with a foot roll, a crystallizer vibration device, a dummy ingot driving device, a billet discharging device, a protective temperature preserving device and a crystallizer electromagnetic agitating device. The crystallizer with the foot roll contacts liquid steel and a steel pipe is formed. An outer layer is a stainless steel water jacket and an outermost layer is a carbon steel outer shell, which are connected by an upper flange and a lower flange. A crystallizer water tank adopts the cold circulation system with one entrance and two exits. The crystallizer vibration device is of non-sine electric form. The utility model has the advantages of novel structure, compact and reasonable configuration, better billet quality and lower cost.

Description

Extra Large Section Round Billet Continuous Casting Machine

technical field

The utility model relates to a round billet/tube billet continuous casting device in the technical field of metallurgical industry continuous casting, in particular to a round billet/tube billet continuous casting device with a diameter of 800-1000 mm.

Background technique

The continuous casting machine is the main equipment of the continuous casting process in the modern metallurgical industry. Its structural characteristics and working principle not only determine the working efficiency and production cost of the continuous casting machine, but also directly affect the product quality. So far, there are mainly three types of billet/round billet continuous casting machines: vertical, horizontal, and full arc, and they are widely used in industrial production practices. Their products are used in petroleum, chemical, machinery and other industries, but in Before the continuous casting machine is put into production, even in the world, whether it is ordinary steel or special steel tube billet/round billet, the maximum cross-section does not exceed

As the country's economic development continues to be optimistic about the market for large seamless steel pipes, the demand for billets with extra large cross-sections is increasing day by day. Before that, large ingots were mostly used as billets, and their output, quality, and yield were not satisfactory. For this reason, we have been While exploring the replacement of continuous casting slabs with extra-large cross-sections, it is a difficult problem that we need to solve to develop a process and equipment for continuous casting machines with extra-large cross-sections with a diameter of 800-1000 mm.

Contents of the invention

The purpose of this utility model is to meet the domestic and foreign new energy wind power generation large-scale bearings, petroleum, chemical industry, machinery, shipbuilding and other industries for forgings, ultra-thick wall seamless steel pipe manufacturing needs, to provide a high-quality, large cross-section tube blank / round Billet vertical continuous casting machine.

The utility model extra-large cross-section round billet continuous casting machine is realized through the following technical measures. The continuous casting machine is characterized by a vertical type, which consists of a crystallizer with foot rollers, a crystallizer vibration device, an ingot supporting device, a billet discharge device, It is composed of protective heat preservation cover, crystallizer electromagnetic stirring device and other parts.

The crystallizer with foot roller is in contact with the molten steel with a copper tube, the outer layer is a stainless steel water jacket, and the outermost layer is a carbon steel shell, which is connected by upper and lower flanges; in order to ensure that the tube billet has sufficient support strength at the lower mouth of the mold The thickness of the shell, the water tank of the crystallizer adopts the system of one inlet, two outlets and one cooling cycle; the taper of the copper tube of the mold is calculated according to the solidification shrinkage parameters of the main steel types given. In order to ensure the size of the water joint, the water jacket requires strict tolerances limit.

Two rows of foot rollers with adjustable clearance are densely distributed under the copper tube of the crystallizer.

The foot roll area is a secondary cooling area, with water mist nozzles evenly distributed, and the water volume is controlled according to the pouring speed of the tube billet and the steel type to be poured. The secondary cooling water is quickly connected by the water receiving plate of the vibrating device.

The crystallizer vibrating device is non-sinusoidal electric, and the frequency can be changed according to different pouring speeds to ensure constant negative slip time. The mold vibrating device is guided by plate rings and driven symmetrically by double servo motors. The first and second cooling water are provided centrally by the water receiving plate of the vibrating device.

The dummy supporting device is composed of rigid dummy rod, dummy head, lifting transmission mechanism, guiding mechanism, etc. The upper part is connected with the rigid dummy rod with special shaped dummy head. To prevent deviation, the surrounding guide mechanism is set; the dummy device is used for pouring operation and leading the casting slab out of the mold and supporting the casting slab, and performs stepless speed regulation according to the casting speed.

The billet discharge device is used for stripping, flipping and conveying of the cast billet. When the dummy supporting device is lowered to the set position, the dummy removing device enters the bottom of the dummy head, and after slow cooling, the dummy bar is separated from the dummy rod and turned over together with the tube billet by the turning mechanism. And place the tube blank on the conveying roller table.

The electromagnetic stirring device of the crystallizer is an external coil placed in the lower part of the crystallizer, and its inner diameter can accommodate the crystallizer and part of the foot roll.

The utility model has advanced technology, novel structure, compact and reasonable configuration, and adopts the vertical type to eliminate the straightening deformation generated when the arc continuous casting machine straightens the tube billet/round billet, which will easily lead to the tube billet produced. / internal defects of the round billet, no indentation defects on the surface of the tube billet / round billet. Compared with the die-casting steel ingots currently used in the manufacture of these products, the billets have the advantages of better quality and lower cost, so the tube billets/round billets produced by this continuous casting machine can replace large die-casting steel ingot. Greatly improve the yield of billet products, thereby saving energy consumption and reducing the discharge of three wastes. Bring greater economic and social benefits to owners. The construction period is short, the investment is low, the operating cost is low; the operation is convenient and the operation is reliable; it fully meets the production requirements.

Description of drawings

Fig. 1 is a structural layout diagram of the extra-large cross-section round billet continuous casting machine of the present invention.

Fig. 2 is a structural diagram of the utility model crystallizer.

Fig. 3 is the crystallizer vibrating device of the present utility model.

Detailed ways

The utility model extra-large cross-section round billet continuous casting machine mainly includes: water-cooled crystallizer 1, crystallizer electromagnetic stirring system 2, crystallizer vibration device 3, ingot supporting device 4, protective insulation section 5, billet discharge device 6, ingot removal device Device 7 and secondary cooling chamber 8 .

The cross-section of the water-cooled crystallizer 1 is very large, and the crystallizer water tank 11 adopts a strong cooling structure design. In order to ensure that the thickness of the exit billet shell meets the requirements, the crystallizer water tank 11 adopts a system of one inlet, two outlets, and one cold cycle. The taper and water gap design of the mold copper tube 9 fully ensure the effective contact heat conduction between the cast slab and the mold surface. Keeping the slab in contact until the exit of the mold reduces possible cracks and surface defects such as dimples. The taper of the mold copper tube is calculated according to the solidification shrinkage parameters of the main steel grades given, and the maximum coverage value is determined so that it can basically adapt to the requirements of different steel grades and pouring conditions. In order to ensure the size of the water joint, the water jacket 10 requires strict tolerance limits. The mold is self-calibrating to ensure a constant water gap under all conditions. The housing is fitted with rubber gaskets, allowing the copper tubes to move freely during alignment. Intermittent changes in the temperature of the copper pipe wall, unstable heat transfer will cause the cooling water to boil. This situation can cause permanent copper tube deformation, and the high wall temperature also increases the precipitation of dissolved salts in the cooling water. Copper tube and copper tube wall thickness are designed to avoid permanent deformation under high temperature working conditions. After reaching the design life, it can be repaired and used for 2 cycles.

The double row of foot rolls 13 below the crystallizer is the casting slab support, and the purpose of adopting the double row of foot rolls is to guide the dummy head to insert into the crystallizer when the dummy rod is put on and to guide the casting slab after it goes out of the mold. If the slab/dummy head is not guided, it may scratch the copper tube wall at the bottom of the mold, shorten the service life of the mold, and cause surface defects in the slab. Practice has proved that the correct use of foot rolls can reduce mold wear and reduce the impact on slab quality under different pouring conditions.

The secondary cooling device is based on the solidification characteristics of the super-large cross-section billet, and adopts the narrow zone secondary cooling method. Only the secondary cooling device in the foot roll area is provided, and the special water channel in the mold and the water receiving plate 17 of the vibration device and the The external water pipes are connected, and the spraying device 12 is evenly distributed with four drainage mist nozzles, and the water volume is controlled according to the pouring speed of the tube blank and the steel type to be poured. Considering the design of the billet with super large cross-section, the ideal cooling distribution is realized according to the distribution law of the heat transfer coefficient of the billet from the forced cooling of the mold to the cooling of the billet by air convection and radiation. A reasonable distribution of cooling intensity effectively determines the length of the liquid core and the average surface temperature of the slab.

The crystallizer electromagnetic stirring device 2 is used to improve the quality of the slab and improve the flexibility of the process operation. The advantage of electromagnetic stirring in the crystallizer is that the number of surface and subcutaneous inclusions is reduced, and their distribution on the cross-section of the slab is more uniform. The centripetal force generated by the swirling of the molten steel can make the inclusions in the molten steel gather in the center to prevent entrainment in the solidified slab shell; it can avoid sticking slag, the molten steel makes the slag leave the mold wall, and the slag gathered in the center of the meniscus is easy to skim off; For carbon steel and low alloy steel, the electromagnetic stirring process technology is used to accelerate the diffusion of concentration along the axis and reduce the central segregation peak. Usually the center segregation degree of these steels is lower than that of high carbon steel, so the main purpose is to ensure a good solid phase structure and reduce the center porosity.

The crystallizer vibrating device 3 is non-sinusoidal electric. The frequency can be changed according to different pouring speeds to ensure constant negative slip time. The crystallizer vibrating device is equipped with a buffer device 14, which uses a plate ring guide 15 and double servo motors 16 to drive symmetrically. The crystallizer vibration device driven by a servo motor can adjust the frequency, amplitude and vibration curve online to ensure the surface quality is guaranteed, the depth of vibration marks is reduced, and the solidified billet shell has sufficient lubrication effect.

The basic factor considered in the selection of vibration parameters is the negative slip time, that is, the time interval during which the movement speed of the mold is faster than that of the slab when the mold and the slab move in the same direction, and its relationship with the vibration parameters is:

NST＝60/πf·arccos(VC×1000/πfs)

In the formula: f - the number of vibrations per minute (l/min)

VC——pouring speed (m/min)

S—stroke (mm)

The frequency is changed according to different pouring speeds to ensure a constant negative slip time, and the results of the changes are automatically controlled by the continuous casting and recorded by the computer.

The water receiving plate 17 of the vibrating device provides the quick connection of primary and secondary cooling water collectively.

Dummy support device 4 is composed of rigid dummy rod, dummy head, lifting transmission mechanism, guiding mechanism, etc. The upper part is connected with the rigid dummy rod with special shaped dummy head. In order to prevent deviation, the surrounding guide mechanism is set. The device adopts motor drive, variable frequency speed regulation, coordinates casting through PLC control and other systems, and can steplessly adjust speed according to process requirements. The dummy device 4 is used for pouring operation and leading the slab out of the crystallizer and supporting the slab.

In order to ensure the quality of the slab, the slab protection and heat preservation section 5 is set to ensure that the slab is slowly cooled to the temperature required by the process to discharge the slab. The heat preservation section is equipped with an observation window and a billet exit door.

The blanking device 6 is composed of equipment such as an ingot stripping device 7, a turning mechanism and a conveying roller table, and is used for stripping, turning, and conveying of the billet. When the dummy dummy device 4 pulls the billet down to the set position, the billet discharge door is opened to open, the overturning mechanism raises the billet, the dummy dummy device 7 enters to disengage the dummy head, and the dummy bar continues to drop to the initial position. The turning mechanism turns over together with the tube blank and puts the tube blank on the conveying roller table and sends it to the slow cooling pit for slow cooling.

The secondary cooling chamber 8 is used to drain the steam generated by the secondary cooling spray in the pouring process, and prevent surrounding equipment from being splashed by water and prevent molten steel from splashing when steel leakage occurs.

The working process of the extra-large cross-section round billet continuous casting machine of the utility model is as follows: when casting Φ800mm pipe billet/round billet, the tundish car drives to the casting position of the continuous casting machine, and the submerged nozzle is aligned with the center of the crystallizer and lowered to the specified position, open the tundish stopper mechanism to inject molten steel into the crystallizer 1 and reach different liquid levels, the crystallizer vibration device 3, electromagnetic stirring device 2, and ingot supporting device 4 are automatically started, and the tube billet will pass through the mold 1 and the foot roller in turn. After the cooling zone, enter the heat preservation zone. The ingot supporting device 4 descends to the specified position, stops pouring, and slowly cools down to the required temperature in the protective heat preservation section 5, and the turning mechanism in the billet ejection device 6 is activated to support the tube billet, then the billet is taken off, turned over to the horizontal position, and is passed by the output roller. Export to the heat preservation pit and slowly cool to room temperature.

The specifications of the billet can be changed by replacing the crystallizer and the dummy head, and can be replaced between Φ800～Φ1000.

Claims (5)

1, a kind of especially big sectional plane round billet continuous casting machine, conticaster is vertical, it is characterized in that: described conticaster is made up of crystallizer, mould vibration device, holder dummy ingot device, knockout mechanism, protection soaking zone, crystallizer electromagnetic mixing apparatus with sufficient roller; Being with sufficient roller crystallizer to contact with molten steel is copper pipe, and skin is the stainless steel water jacket, and outermost layer is the carbon steel shell, and it connects by last lower flange, and the crystallizer water tank adopts one to advance scene 2 one cold circulation standard; Mould vibration device is the non-sine powered version, can change frequency to guarantee the constant of negative slip time according to different poring rates; Casting blank of continuous casting machine diameter range Φ 800～Φ 1000mm.

2, especially big sectional plane round billet continuous casting machine according to claim 1 is characterized in that: the adjustable sufficient roller of densely covered down two rows of crystallizer copper pipe, sufficient roller district is provided with the water smoke spray equipment, carries out water yield control according to pipe poring rate and the steel grade of being poured into a mould.

3, especially big sectional plane round billet continuous casting machine according to claim 1 is characterized in that: mould vibration device adopts plate ring guiding, and two servomotor symmetries drive non-sinusoidal oscillation.

4, especially big sectional plane round billet continuous casting machine according to claim 1, it is characterized in that: holder dummy ingot device is made up of rigid dummy bar, dummy bar head, elevating drive mechanism, guiding mechanism etc., top is dummy bar head, dummy bar head is connected with rigid dummy bar, and elevating drive mechanism adopts the frequency control motor transmission.

5, especially big sectional plane round billet continuous casting machine according to claim 1, it is characterized in that: knockout mechanism is made up of deingot device, switching mechanism and rollgang, be used for strand and take off ingot, upset, conveying, when holder dummy ingot device drops to desired location, switching mechanism rises, the deingot device enters the disengagement dummy bar head, and switching mechanism overturns together with pipe and places rollgang to send pipe.

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