CN214977620U

CN214977620U - Slab caster vertical section secondary cooling nozzle cooling structure

Info

Publication number: CN214977620U
Application number: CN202023276749.9U
Authority: CN
Inventors: 张乔英; 周寿好; 邓勇; 张建; 王吉; 钟鹏; 臧红臣; 常正昇; 杨克枝
Original assignee: Maanshan Iron and Steel Co Ltd
Current assignee: Maanshan Iron and Steel Co Ltd
Priority date: 2020-12-29
Filing date: 2020-12-29
Publication date: 2021-12-03
Anticipated expiration: 2030-12-29

Abstract

The utility model discloses a two cold spray nozzle cooling structures in slab caster vertical section belongs to slab continuous casting cooling control technical field. The method comprises the steps that seven nozzles are correspondingly arranged on an inner arc and an outer arc of a roller gap of a sectional roller along the width direction at the vertical section of a continuous casting machine respectively, the seven nozzles are numbered to be (C) - (C) in sequence on the same arc side, the nozzle (C) is arranged in the center of the roller gap width, the other six nozzles are symmetrically arranged relative to the nozzles, the nozzle (C), the nozzle (d) and the nozzle (C) of the inner arc and the outer arc are connected through the same pipeline and marked as a loop A, and the nozzle (C) of the inner arc and the outer arc are connected through the same pipeline and marked as a loop B. Can improve the effective utilization rate of secondary cooling water, and is beneficial to cost reduction and efficiency improvement.

Description

Slab caster vertical section secondary cooling nozzle cooling structure

Technical Field

The utility model belongs to the technical field of slab continuous casting cooling control, more specifically says, relates to a two cold spray nozzle cooling structures in slab caster vertical section.

Background

The continuous casting process is a process of continuously casting high-temperature molten steel with qualified components and cleanliness obtained in the steelmaking-refining process into a casting blank meeting the specification requirements through complete equipment, and qualified blanks are provided for a hot rolling process. High quality of the cast slab is an important guarantee for obtaining high quality finished products, so the quality control of the cast slab in the continuous casting process becomes an important research content of metallurgy workers. Particularly for microalloyed steel, a corner transverse crack defect is easy to form, and adverse effects are caused on subsequent rolling. For microalloyed steel, the surface structure grains can be refined through the control of the surface structure of a casting blank, the precipitation of a ferrite film at an austenite grain boundary in the phase transformation process is inhibited, and the crack defect caused by stress concentration in the bending or straightening process of the casting blank is prevented. For the control method, secondary cooling control after the casting blank exits the crystallizer is a key, and the arrangement mode of nozzles in a secondary cooling area, the amount of cooling water and loop control are key optimization directions. For straight arc slab caster, the nozzle arrangement and loop control of the vertical sector is more important. The mode that the inner arc and the outer arc stagger and set up is often adopted to the vertical section nozzle of most present casting machines, and control circuit is single relatively, and when different width casting blanks were cast to same casting machine, the casting blank bight region caused the subcooling easily, leads to the emergence of bight crackle easily. Therefore, there is a need for a new vertical segment secondary cooling nozzle arrangement and loop control method for slab caster.

The Chinese patent application numbers are: 201510097887.5, publication date is: 2015-05-13, the invention relates to a method for arranging secondary cooling nozzles and a secondary cooling control method for improving the surface plasticity of a casting blank, the method for arranging secondary cooling nozzles and the secondary cooling control method are characterized in that wide nozzles and narrow nozzles are arranged at a vertical section of a continuous casting machine, the nozzles are staggered in odd-even rows, and the number of the nozzles is different according to the thickness and the width of the casting blank; the wide-surface nozzle and the narrow-surface nozzle respectively adopt an independent loop control method so as to improve the surface plasticity of the casting blank.

The Chinese patent application numbers are: 201220689422.0, the announcement date is: 2013-06-19, which comprises a plurality of rows of nozzles arranged on a slab; 3-4 nozzles are arranged in each row along the width direction of the plate blank; wherein, 1-2 fixed nozzles are arranged in the middle of each row, and a movable nozzle is arranged at each edge. Through the movable gas-water nozzle cooling system, when the production section of the slab changes, the covering range of secondary cooling water is adjusted by moving the position of the gas-water nozzle relative to the slab, so that the corner transverse cracks formed due to corner supercooling in the slab straightening process are reduced, and the requirement of a slab continuous casting machine for producing multi-section high-surface-quality slabs is met. The cooling condition is adjusted through the movable nozzle, and although the cooling condition of the plate blank can be improved, continuous detection needs to be carried out on the site.

The Chinese patent application numbers are: 201310404957.8, publication date is: 2013-12-25, which relates to a secondary cooling nozzle arrangement method for continuous casting production of silicon steel slabs, and comprises the following steps: in the vertical bending section, six spray nozzles are arranged in the width direction of an inner arc and an outer arc of each roll gap of a continuous casting machine to spray a continuous casting blank, wherein four spray nozzles are arranged in the middle, and the other two spray nozzles are arranged at the edge; four nozzles are arranged in the width directions of an inner arc and an outer arc of each roll gap of the continuous casting machine in the arc section and the straightening section for spraying continuous casting billets, wherein two nozzles are arranged in the middle, and the other two nozzles are arranged at the edge; in the horizontal section, two nozzles are arranged in the width direction of the inner arc and the outer arc of each roll gap of the continuous casting machine to spray the continuous casting blank, and one nozzle sprays the continuous casting roll. Adopt the utility model discloses a nozzle setting method, the homogeneity of the horizontal temperature of casting blank has had very big improvement, and has eliminated the angle crack basically, has satisfied the different two cold regional cooling strength demands of production of silicon steel simultaneously.

Disclosure of Invention

1. Problems to be solved

To the limited problem of current casting blank bight cooling, the utility model provides a two cold nozzle cooling structures in slab caster vertical section. Can improve the effective utilization rate of secondary cooling water, and is beneficial to cost reduction and efficiency improvement.

2. Technical scheme

In order to solve the above problem, the utility model discloses the technical scheme who adopts as follows:

the utility model discloses a two cold spray nozzle cooling structures in slab caster vertical section, include at the conticaster vertical section, the inner arc and the outer arc along width direction merogenesis roller gap correspond respectively and set up seven nozzles, same arc side, it is (r) -the seventeen to number seven nozzles according to the order, No. four the nozzle sets up at the roll gap width center, all the other six nozzles set up about this nozzle symmetry, No. three nozzles with inner arc and outer arc, No. four nozzle and No. five nozzles use same pipe connection, mark as the A return circuit, No. two nozzles with the nozzle of inner arc and outer arc and No. sixteen nozzles use same pipe connection, mark as the B return circuit, use same pipe connection with all the other nozzles, mark as the C return circuit.

As a further illustration of possible embodiments of the present invention, the a loop, the B loop and the C loop use different water inlet pipes for water supply, respectively.

As a further illustration of a possible embodiment of the invention, the nozzle spray angle of the inner and outer arcs is 80-100 °. The spray angle of the nozzle is controlled, the nozzle is effectively utilized to cool the casting blank, the cooling effect is good, and the cooling resource is saved.

As a further illustration of a possible embodiment of the present invention, the nozzle spray angle of the inner and outer arcs is 90 °.

As a further illustration of a possible embodiment of the invention, the distance between the nozzles adjacent to the inner and outer arcs is 280-320 mm. Because the space of the roll gap of the sectional roll is limited, the distance between the nozzles needs to be adjusted to realize the uniform distribution of the nozzles and effectively finish the cooling of the casting blank.

As a further illustration of a possible embodiment of the invention, the distance from the nozzle end faces of the inner and outer arcs to the casting blank surface is the same. The inner arc and the outer arc are arranged in an identical and symmetrical mode, two sides can be conveniently and equivalently controlled, and control is simple.

As a further illustration of a possible embodiment of the present invention, the distance from the nozzle end surface of the inner arc and the outer arc to the casting blank surface is 160-180 mm. The distance from the end face of the nozzle to the surface of the casting blank needs to be controlled, the distance is too large, cooling water cannot effectively reach the surface of the casting blank, the distance is too small, and the cooling range is small.

3. Advantageous effects

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

(1) the utility model discloses a slab caster vertical section secondary cooling nozzle cooling structure, the nozzle of different positions is controlled alone, to the casting blank of different sections, different return circuits can set up different cooling water volumes, in order to satisfy the casting blank cooling control requirement, especially to the cooling control of casting blank bight; in addition, the loop control can improve the effective utilization rate of secondary cooling water, thereby being beneficial to cost reduction and efficiency improvement;

(2) the utility model discloses a slab caster vertical section secondary cooling nozzle cooling structure, and the method that the inner and outer arc nozzle of different positions adopted independent loop control, and different cooling water volumes can be set up to return circuit A, B and C, are favorable to more reasonable control casting blank surface temperature, prevent the supercooling of casting blank bight;

(3) the utility model discloses a slab caster vertical section secondary cooling nozzle cooling structure, according to steel grade and casting blank width, cooperation crystallizer cooling, the sufficient roller cooling of crystallizer wide and narrow face more are favorable to refining of casting blank top layer grain structure, restrain ferrite film in the phase transition and separate out at austenite grain boundary, and then prevent the casting blank in the bending or stress concentration in the aligning process and take place the crack defect; the method has the characteristics of convenient transformation, capability of preventing the supercooling of the corners of the casting blank, contribution to refining surface structure grains and reduction of the incidence rate of corner cracks;

drawings

The technical solution of the present invention will be described in further detail with reference to the accompanying drawings and examples, but it should be understood that these drawings are designed for illustrative purposes only and thus are not intended to limit the scope of the present invention. Furthermore, unless otherwise indicated, the drawings are intended to be illustrative of the structural configurations described herein and are not necessarily drawn to scale.

FIG. 1 is a schematic view of a nozzle arrangement and circuit control employed by the present invention;

fig. 2 is a schematic view of the cross-sectional nozzle arrangement and spray of fig. 1.

In the drawings: 1. a sectional roller; 2. a secondary cooling nozzle.

Detailed Description

The following detailed description of exemplary embodiments of the invention refers to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration exemplary embodiments in which the invention may be practiced. Although these exemplary embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, it should be understood that other embodiments may be realized and that various changes to the invention may be made without departing from the spirit and scope of the present invention. The following more detailed description of the embodiments of the present invention is not intended to limit the scope of the invention, as claimed, but is presented for purposes of illustration only and not limitation to provide the best mode contemplated for carrying out the invention and to enable any person skilled in the art to practice the invention. Accordingly, the scope of the invention is to be limited only by the following claims.

The detailed description and exemplary embodiments of the invention may be better understood when read in conjunction with the following drawings, where the elements and features of the invention are identified by reference numerals.

The description of the nozzles in this application is for the two-cold nozzle 2 which is numbered to avoid confusion in the description.

Example 1

As shown in fig. 1 and 2, in the cooling structure of the secondary cooling nozzle in the vertical section of the slab caster of the present embodiment, seven nozzles are respectively and correspondingly arranged along the inner arc and the outer arc of the roll gap of the sectional roll 1 in the width direction in the vertical section of the caster, the seven nozzles are numbered as (a), (B), (C) and (C) in sequence, the nozzle (C) and the nozzle (C) in the inner arc and the outer arc are connected by using the same pipe, and the nozzle (C) in the inner arc and the nozzle (C) in the outer arc are connected by using the same pipe. As a further illustration of possible embodiments of the present invention, the a loop, the B loop and the C loop use different water inlet pipes for water supply, respectively.

The loop A, the loop B and the loop C respectively use different water inlet pipelines for supplying water, and the casting blank is cooled by using water. The nozzle spray angles of the inner and outer arcs may be 80 °, 85 °, 90 °, 95 °, 100 ° at 80-100 ° spray angles. The spray angle of the nozzle is controlled, the nozzle is effectively utilized to cool the casting blank, the cooling effect is good, and the cooling resource is saved. The distance between the nozzles of the adjacent inner arcs and the adjacent outer arcs is 280-320 mm, and the distance can be 280mm, 290mm, 300mm, 310mm and 320 mm. Because the space of the roll gap of the sectional roll 1 is limited, the distance between the nozzles needs to be adjusted to realize the uniform distribution of the nozzles and effectively finish the cooling of the casting blank. The distances from the nozzle end surfaces of the inner arc and the outer arc to the surface of the casting blank are the same. The inner arc and the outer arc are arranged in an identical and symmetrical mode, two sides can be conveniently and equivalently controlled, and control is simple. The distance between the nozzle end faces of the inner arc and the outer arc and the surface of the casting blank is 160-180 mm, and specifically 160mm, 165mm, 170mm, 175mm and 180 mm. The distance from the end face of the nozzle to the surface of the casting blank needs to be controlled, the distance is too large, cooling water cannot effectively reach the surface of the casting blank, the distance is too small, and the cooling range is small.

Example 2

The present embodiment proposes detailed implementation contents on the basis of embodiment 1. The slab caster vertical section secondary cooling nozzle cooling structure of this embodiment adopts straight conventional slab caster of arc, and its metallurgical length is 33.2m, and the arc radius is 10.9m, includes 15 fan-shaped sections, adopts 7 curved 7 points straightening, and the castable width is 950 ~ 2150 mm. The wide-surface foot roller spray ring cooling and the narrow-surface foot roller cooling of the crystallizer of the casting machine are both cooled by pure water and are controlled by independent loops.

Selecting Q345E steel, wherein the casting section of the casting blank is 230mm multiplied by 1400mm, and the casting speed is 1.3 m/min.

With reference to fig. 1 and 2, the arrangement structure of the vertical section secondary cooling nozzle 2 is specifically as follows: in the vertical section of the continuous casting machine, the secondary cooling nozzles 2 and the cooling loop are arranged according to the content of the embodiment 1, the distance between every two adjacent secondary cooling nozzles 2 is 300mm, and the distance between the end surface of each secondary cooling nozzle 2 and the surface of a casting blank is 170 mm; the secondary cooling nozzles 2 of the inner arc and the outer arc of each roll gap in the width direction are arranged oppositely, and the central lines of the secondary cooling nozzles 2 in the same row are also in the same plane in the vertical direction of the same arc side. The injection angle of the secondary cooling nozzle 2 is 90 degrees. The cooling mode is pure water cooling, according to the embodiment, the cooling water amount of the loop A is set to be 420L/min, the cooling water amount of the loop B is 210L/min, the cooling water amount of the loop C is 110L/min, in addition, the water flow speeds of the wide-surface water tank and the narrow-surface water tank of the crystallizer are set to be 6.8m/s and 6.7m/s respectively, the temperature of the cooling water inlet of the crystallizer is controlled to be 25-28 ℃, the water amount of the wide-surface foot roll spray ring cooling loop of the crystallizer is 400L/min, and the water amount of the narrow-surface foot roll cooling loop is 260L/min.

After the scheme is implemented, the temperature of the corner of the casting blank at the straightening point is increased by 100 ℃, and the corner is effectively prevented from being supercooled. Metallographic results of casting blank corner samples show that surface layer grains are refined to 0.7-0.9 mm. The incidence rate of the rolling hot rolling reaction crack defect of the uncleaned casting blank corner is reduced to 3.6 percent from the original 15 percent.

Example 3

The cooling structure of the vertical section secondary cooling nozzle of the slab caster in this embodiment is the same as that in embodiment 2 except for the following technical parameters.

Selecting Q345R steel, wherein the casting section of the casting blank is 230mm multiplied by 2050mm, and the casting speed is 1.0 m/mim.

The cooling mode is pure water cooling, according to the embodiment, the cooling water amount of the loop A is set to be 530L/min, the cooling water amount of the loop B is set to be 320L/min, the cooling water amount of the loop C is set to be 210L/min, and the water flow velocities of the wide-surface water tank and the narrow-surface water tank of the crystallizer are respectively 6.6m/s and 6.5 m/s. The water quantity of a cooling loop of the wide-face foot roller spray ring of the crystallizer is 500L/min, and the water quantity of a cooling loop of the narrow-face foot roller is 380L/min.

After the scheme is implemented, the temperature of the corner of the casting blank at the straightening point is increased by 80 ℃, and the corner is effectively prevented from being supercooled. Metallographic results of casting blank corner samples show that surface layer grains are refined to 0.6-0.8 mm. The incidence rate of the rolling hot rolling reaction crack defect of the uncleaned casting blank corner is reduced to 3.2 percent from the original 10 percent.

Claims

1. The utility model provides a two cold spray nozzle cooling structures in slab caster vertical section which characterized in that: the method comprises the steps that seven nozzles are correspondingly arranged on an inner arc and an outer arc of a roller gap of a sectional roller along the width direction at the vertical section of a continuous casting machine respectively, the seven nozzles are numbered to be (C) - (C) in sequence on the same arc side, the nozzle (C) is arranged at the center of the roller gap, the other six nozzles are symmetrically arranged relative to the nozzles, the nozzle (C) and the nozzle (C) of the inner arc and the outer arc are connected through the same pipeline and marked as a loop A, and the nozzle (C) of the inner arc and the outer arc are connected through the same pipeline and marked as a loop B.

2. The slab caster vertical section secondary cooling nozzle cooling structure as claimed in claim 1, characterized in that: and the loop A, the loop B and the loop C respectively use different water inlet pipelines to supply water.

3. The slab caster vertical section secondary cooling nozzle cooling structure as claimed in claim 1, characterized in that: the nozzle spray angle of the inner arc and the outer arc is 80-100 degrees.

4. The slab caster vertical section secondary cooling nozzle cooling structure as claimed in claim 3, characterized in that: the nozzle spray angles of the inner and outer arcs are 90 °.

5. The slab caster vertical section secondary cooling nozzle cooling structure as claimed in claim 1, characterized in that: and the distance between the adjacent nozzles of the inner arc and the outer arc is 280-320 mm.

6. The slab caster vertical section secondary cooling nozzle cooling structure as claimed in claim 5, characterized in that: and the distances from the nozzle end surfaces of the inner arc and the outer arc to the surface of the casting blank are the same.

7. The slab caster vertical section secondary cooling nozzle cooling structure as claimed in claim 1, characterized in that: and the distance between the nozzle end surfaces of the inner arc and the outer arc and the surface of the casting blank is 160-180 mm.