CN217616819U - Hot rolling strip steel production line - Google Patents

Abstract

The utility model relates to a hot rolling strip steel production line, belonging to the strip steel continuous casting and rolling technical field, comprising a slab caster, a roughing mill group, a first shearing device, a first heating device, a middle mill group, a second heating device, a finishing mill group, a cooling device after rolling, a high-speed flying shear and a coiling machine group which are connected in sequence by a roller way along the rolling direction; the roughing mill group comprises two roughing mill frames which are sequentially arranged along the rolling direction; the intermediate rolling mill group comprises an intermediate rolling mill frame. The utility model discloses a reasonable production line overall arrangement has not only improved the production efficiency of high carbon steel in the continuous casting and rolling production line, has still reduced the surely decrease of production line and has judged useless rate to line benefit has been improved.

Description

Hot-rolled strip steel production line

Technical Field

The utility model belongs to the technical field of belted steel continuous casting and rolling, a hot rolling belted steel production line is related to, especially relate to a well, high carbon steel continuous casting and rolling headless rolling production line.

Background

The thin slab caster test was successfully carried out by Simmark in Germany in 1986, and the first CSP plant in the world was established by Nilexwell in Indiana in New York Steel, USA, in 1989, indicating that the technology of continuous casting and rolling of thin slabs was put into industrial production. Thereafter, various steel/engineering companies in the world have developed new continuous thin slab casting and rolling technologies, such as ISP technology of demark corporation, germany, CONROLL technology of austria, QSP technology of sumitomo corporation, FTSR technology of tanill corporation, ESP technology of avidi corporation, italy, and ASP technology of saddle steel, china. Among them, the CSP technique is most widely used, and accounts for more than 50% of the global market share. ESP is the latest continuous casting and rolling process of endless strip steel, and rapidly occupies the newly added market of continuous casting and rolling by the characteristics of small floor space, compact structure, high production efficiency and the like.

The continuous casting and rolling of thin slabs is the main production means for obtaining thin and ultra-thin hot rolled plates, and as the application time is prolonged, some production line problems become more and more prominent. For example, in a continuous casting and rolling production line for endless rolling, because the continuous casting and rolling parts are rigidly connected and limited by the continuous casting and blank drawing speed, the speed of a production line at a rolling section is difficult to increase, so that the temperature of a thin slab is excessively reduced in the production process, and the production process requirements of part of steel types (such as medium carbon steel and high carbon steel) cannot be met; when one casting time of continuous casting and rolling starts, the continuous casting and billet drawing speed is low, the speed of a steel rolling section production line is also correspondingly low, the process temperature of a plurality of coils of steel before the casting time cannot meet the production process requirement, only judgment or waste treatment can be carried out, and the economic benefit of the production line is reduced. In addition, when one casting time of continuous casting and rolling starts, in order to verify the pressing reliability of the roughing mill, a wedge-shaped blank exists and is subjected to waste blank cutting treatment, so that the product yield of a production line is reduced.

SUMMERY OF THE UTILITY MODEL

In view of this, the present invention provides a hot rolled strip steel production line to improve the yield of the product.

In order to achieve the above purpose, the utility model provides a following technical scheme:

a hot-rolled strip steel production line comprises a slab continuous casting machine, a rough rolling unit, a first shearing device, a first heating device, a middle rolling unit, a second heating device, a finishing rolling unit, a cooling device after rolling, a high-speed flying shear and a coiling unit which are sequentially connected through a roller way along the rolling direction; the roughing mill group comprises two roughing mill frames which are sequentially arranged along the rolling direction; the middle rolling mill group comprises a middle rolling mill frame.

Optionally, the finishing mill group comprises 4 to 5 finishing mill stands arranged in sequence along the rolling direction.

Optionally, an iron scale removing device is arranged at an inlet of the finishing mill group.

Optionally, the scale removing device is a high-pressure water descaling device.

Optionally, an iron scale removing device is arranged at the inlet of the roughing mill group and/or the intermediate mill group.

Optionally, the scale removing device is any one of a high-pressure water descaling device, a rotary jet descaling device and a flame cleaning type descaling device.

Optionally, the first shearing device is a pendulum shear, and a slab pushing and stacking device is arranged at an outlet of the first shearing device.

Optionally, a second shearing device is arranged between the middle rolling mill group and the second heating device.

Optionally, the second shearing device is a pendulum shear or a drum flying shear, and a waste removing device is arranged at an outlet of the second shearing device.

Optionally, the first heating device is a longitudinal magnetic induction heating furnace; the second heating device is a transverse magnetic induction heating furnace or a longitudinal magnetic induction heating furnace.

The beneficial effects of the utility model reside in that:

1. the cutting and shearing device is arranged between the roughing mill group and the first heating device and between the intermediate mill group and the second heating device, so that head warping caused by slab rolling deformation can be cut off, and the heating device can be prevented from being damaged by warping defects.

2. The roughing mill set is set into two roughing stands, and the intermediate mill set is set into one intermediate mill stand, so that the waste cutting quantity of the wedge-shaped blank caused by the pressing-down detection of the roughing mill at the beginning of the casting time can be reduced, and the yield of products is improved.

3. Through the setting of first heating device and second heating device, increased the ability of mending temperature, mended the temperature to the first several coiled band steel of low-speed production when watering time begins, made its temperature satisfy technological temperature requirement and normal production, reduced the improvement or the waste product handling capacity of the first several coiled band steels in watering time.

4. Through the arrangement of the first heating device and the second heating device, the temperature supplementing capacity is increased, the temperature of low-drawing-speed production steel (such as medium carbon steel and high carbon steel) caused by chemical composition reasons is supplemented, the temperature meets the process temperature requirement and normal production is realized, the product outline of the continuous casting and rolling production line is expanded, the problem that the product variety of the existing endless rolling continuous casting and rolling production line is limited is solved, and the market adaptability and the competitiveness of the endless rolling continuous casting and rolling production line are improved.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the means of the instrumentalities and/or combinations particularly pointed out in the appended claims.

Drawings

For the purposes of promoting a better understanding of the objects, features and advantages of the invention, reference will now be made to the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic layout view of the production line of the hot-rolled strip steel of the present invention.

Reference numerals: the system comprises a slab continuous casting machine 1, a rough descaling device 2, a rough rolling unit 3, a pendulum shear 4, a slab pushing and stacking device 5, a first heating device 6, an intermediate descaling device 7, a middle rolling unit 8, a rotary drum flying shear 9, a scrap removing device 10, a second heating device 11, a fine descaling device 12, a fine rolling unit 13, a laminar cooling device 14, a high-speed flying shear 15 and a coiler 16.

Detailed Description

The following embodiments of the present invention are provided by way of specific examples, and other advantages and effects of the present invention will be readily apparent to those skilled in the art from the disclosure herein. The present invention can also be implemented or applied through other different specific embodiments, and various details in the present specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the drawings provided in the following embodiments are only for illustrating the basic idea of the present invention, and the features in the following embodiments and examples may be combined with each other without conflict.

Wherein the showings are for the purpose of illustrating the invention only and not for the purpose of limiting the same, and in which there is shown by way of illustration only and not in any way limiting the scope of the invention; for a better understanding of the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.

The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", "front", "back", etc., indicating directions or positional relationships based on the directions or positional relationships shown in the drawings, it is only for convenience of description and simplification of description, but it is not intended to indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore, the terms describing the positional relationships in the drawings are only used for illustrative purposes and are not to be construed as limiting the present invention, and those skilled in the art can understand the specific meanings of the terms according to specific situations.

Referring to fig. 1, a hot-rolled strip steel production line comprises a slab continuous casting machine 1, a rough rolling unit 3, a pendulum shear 4, a first heating device 6, a middle rolling unit 8, a rotary drum flying shear 9, a second heating device 11, a finishing rolling unit 13, a cooling device after rolling, a high-speed flying shear 15 and a coiling unit which are sequentially connected through a roller way along a rolling direction; the roughing mill group 3 comprises two roughing stands arranged in sequence along the rolling direction; the intermediate rolling train 8 comprises an intermediate rolling stand. The first heating means 6 and the second heating means 11 are intended to provide temperature compensation to the intermediate blank passing therethrough.

The utility model discloses between roughing mill group 3 and first heating device 6, all be equipped with shearing mechanism between well rolling mill group 8 and the second heating device 11 for the head warpage that the rolling deformation of excision slab produced can prevent that the warpage defect from causing the damage to heating device.

Optionally, the finishing mill group 13 includes 4 to 5 finishing mill stands arranged in sequence along the rolling direction; iron scale removing devices are arranged at the inlets of the rough rolling unit 3, the middle rolling unit 8 and the finishing rolling unit 13; the scale removing device in front of the roughing mill group 3 and the intermediate mill group 8 is any one of a high-pressure water descaling device, a rotary jet descaling device and a flame cleaning type descaling device; the scale removing device in front of the finishing mill group 13 is a high-pressure water descaling device; a slab pushing and stacking device 5 is arranged at the outlet of the pendulum shears 4, and slabs cut by the pendulum shears 4 can be pushed out of the production line and stored; a waste removing device 10 is arranged at an outlet of the drum flying shear 9, and waste steel sheared by the drum flying shear 9 can be stored and taken off line; the first heating device 6 is a longitudinal magnetic induction heating furnace; the second heating device 11 is a transverse magnetic induction heating furnace or a longitudinal magnetic induction heating furnace.

The present invention will be described with reference to the following examples:

the strip steel production line shown in the figure 1 is provided and comprises a slab continuous casting machine 1, a rough descaling device 2, a rough rolling unit 3, a pendulum shear 4, a slab pushing and stacking device 5, a first heating device 6, an intermediate descaling device 7, a middle rolling unit 8, a rotary drum flying shear 9, a waste removing device 10, a second heating device 11, a fine descaling device 12, a fine rolling unit 13, a laminar cooling device 14, a high-speed flying shear 15 and a coiler 16 which are sequentially connected through a roller way. Wherein, the roughing mill group 3 comprises two roughing mill frames which are arranged in sequence along the rolling direction; the intermediate mill train 8 includes an intermediate mill stand, and the finishing mill train 13 includes 5 finishing mill stands arranged in sequence in the rolling direction.

Example one

The casting blank comprises the following raw materials in percentage by mass: c:0.047%, mn:0.12%, si:0.02%, P:0.011%, S:0.003%, als:0.023 percent and the balance of Fe and impurities.

The raw materials are smelted and cast into a blank in a continuous casting machine, the continuous casting drawing speed is 5.5m/min, and the thickness of the continuous casting blank is 95mm.

The casting blank at the outlet of the continuous casting is subjected to rough descaling by a rough descaling device 2 and high-pressure water of 20MPa, then enters a rough rolling unit 3 to be rolled into an intermediate blank of 18.5mm, the outlet temperature of the rough rolling is 1012 ℃, and then sequentially passes through a pendulum shear 4 and a slab pushing and stacking device 5, then enters a first heating device 6 to be heated, the outlet temperature of the first heating device 6 is controlled to be 1038 ℃, then enters a medium rolling unit 8 to be rolled into an intermediate blank of 9mm in thickness, the outlet temperature of the intermediate rolling unit is 913 ℃, the intermediate blank leaves the medium rolling unit, then passes through a rotary drum flying shear 9 and a waste removing device 10, and then enters a second heating device 11 to be heated, the outlet temperature of induction heating is 1125 ℃, the intermediate billet is subjected to high-pressure water descaling by a fine descaling device 12 before entering a finishing mill group 13, the pressure of the descaling water is 38MPa, the intermediate billet after descaling enters the finishing mill group 13 for rolling, the intermediate billet is rolled into finished strip steel with the thickness of 1mm by a 5-stand finishing mill, the inlet temperature of the finishing mill group 13 is 989 ℃, the finishing temperature is 853 ℃, after finishing rolling, the strip steel is subjected to controlled cooling by a laminar flow cooling device 14, the opening water amount is 630m < 3 >/h, the strip steel is cooled to 660 ℃ for coiling, when the coil weight meets the set requirement, a high-speed flying shear 15 is adopted for splitting, and 3 underground recoiling machines 16 work alternately.

In this example, the thickness of the finished strip steel product is 1.0mm, the tensile strength is 354MPa, the yield strength is 275MPa, the yield ratio is 0.77, and the elongation is 38.8%.

Example two

The casting blank comprises the following raw materials in percentage by mass: c:0.65%, mn:1.05%, si:0.25%, P:0.01%, S:0.002%, als:0.022 percent, and the balance of Fe and impurities.

The raw materials are smelted and cast into a blank in a continuous casting machine, the continuous casting drawing speed is 4.5m/min, and the thickness of the continuous casting blank is 105mm.

The continuous casting blank enters a roughing mill group 3 to be rolled into an intermediate blank with the thickness of 26.5mm, the temperature of a roughing outlet is 1002 ℃, the intermediate blank sequentially passes through a pendulum shear 4 and a plate blank pushing and stacking device 5, then enters a first heating device 6 to be heated, the temperature of an outlet of the first heating device 6 is controlled to be 1042 ℃, then enters a middle mill group 8 to be rolled into an intermediate blank with the thickness of 14.6mm, the temperature of an outlet of the middle mill group is 948 ℃, the intermediate blank leaves the middle mill group and then passes through a rotary drum flying shear 9 and a waste removing device 10, then enters a second heating device 11 to be heated, the temperature of an induction heating outlet is 1149 ℃, the intermediate blank is firstly subjected to high-pressure water descaling through an intermediate descaling device 7 before entering a finishing mill group 13, the descaling water pressure is 38MPa, the descaled intermediate blank enters a finishing mill group 13 to be rolled, the finished product strip steel with the thickness of 2.3mm is rolled through a 5-stand finishing mill, the inlet temperature of the finishing mill group 13 ℃, the finishing temperature is 843 ℃, the finished product strip steel is subjected to controlled cooling through a laminar cooling device 14, the strip steel, the finishing mill is rolled into a coiling machine, the finishing mill, the strip steel, the finishing mill, the coiling and the coiling is performed at the finishing mill, and the coiling is performed at the requirement of a coiling station, and the coiling is performed when the finishing mill is set at a high-speed, and the coiling station, and the coiling is set for 16 ℃, and the coiling is performed.

In this example, the thickness of the finished strip steel product is 2.3mm, the tensile strength is 735MPa, the yield strength is 455MPa, the yield ratio is 0.62, and the elongation is 16.8%.

EXAMPLE III

The casting blank comprises the following raw materials in percentage by mass: c:0.01%, mn:0.1%, si:0.018%, P:0.01%, S:0.003%, als:0.021%, and the balance Fe and impurities.

The raw materials are smelted and cast into a blank in a continuous casting machine, the continuous casting drawing speed is 5.5m/min, and the thickness of the continuous casting blank is 95mm.

The casting blank at the outlet of continuous casting is roughly descaled by adopting high-pressure water of 20MPa, enters a roughing mill set 3 to be rolled into an intermediate blank of 18.5mm, the outlet temperature of the roughing mill is 1012 ℃, then sequentially passes through a pendulum shear 4 and a slab pushing and stacking device 5, then enters a first heating device 6 to be heated, the outlet temperature of the first heating device 6 is controlled to be 1038 ℃, then enters a medium mill set 8 to be rolled into an intermediate blank of 9mm thickness, the outlet temperature of the medium mill set 8 is 913 ℃, the intermediate blank leaves the medium mill set 8, then passes through a drum flying shear 9 and a waste removing device 10, and then enters a second heating device 11 to be heated, the outlet temperature of the second heating device 11 is 1125 ℃, the intermediate billet is subjected to high-pressure water descaling through the intermediate descaling device 7 before entering the finishing mill group 13, the descaling water pressure is 38MPa, the intermediate billet after descaling enters the finishing mill group 13 to be subjected to ferrite rolling, the intermediate billet is rolled into a finished strip steel with the thickness of 1.2mm through a 4-stand finishing mill, the inlet temperature of the finishing mill group 13 is 856 ℃, the finishing temperature is 783 ℃, after finishing rolling, air cooling passes through a laminar cooling section, the strip steel is cooled to 680 ℃ to be coiled, when the coil weight meets the set requirement, the strip steel is cut by adopting a high-speed flying shear 15, and 3 underground recoiling machines 16 work alternately.

In this example, the thickness of the finished strip steel product is 1.2mm, the tensile strength is 304MPa, the yield strength is 195MPa, the yield ratio is 0.64, and the elongation is 40.6%.

Example four

The casting blank comprises the following raw materials in percentage by mass: c:0.017%, mn:0.1%, si:0.02%, P:0.012%, S:0.002%, als:0.023 percent, and the balance of Fe and impurities.

After one casting time is started, the raw material molten steel of the casting blank is solidified into a blank shell in the crystallizer, the casting blank with the liquid core is pulled by a dummy bar to leave the lower opening of the crystallizer and move downwards to a horizontal section through a foot roller, a bending section and an arc section, when the head of the casting blank reaches a steel rolling rough rolling area, the thickness of the casting blank is 105mm, and the pulling speed is about 4m/mim. When the tail part of the dummy bar passes through the pendulum shears 4 behind the roughing mill set 3, the pendulum shears 4 shear the casting blank, and after the dummy bar is separated from the pendulum shears 4, the overhead travelling crane separates the dummy bar. When the quality of the casting blank meets the requirement, the first roughing stand starts to be pressed down, and the swing shears 4 shear the first wedge-shaped blank so as to check whether the working state of the first roughing stand meets the requirement; and after the first roughing stand is pressed down to meet the requirement, the second roughing stand starts to be pressed down, and the pendulum shears 4 shear the second wedge-shaped blank so as to check whether the working state of the second roughing stand meets the requirement. When the working states of all the rough rolling stands are checked to be normal, the pendulum shears 4 stop shearing, and the intermediate billets sequentially penetrate through the strip and enter a rolling line until the recoiling machine 16 winds and establishes tension, so that continuous production is started.

Because the blank drawing speed of the continuous casting blank is low in the casting starting stage, the temperature drop amplitude is large in the rolling process of the strip steel of 2-3 coils at the head of the casting time, the temperature of the strip blank is increased by 180 ℃ by the first heating device 6 and the second heating device 11, the final rolling temperature of the cast steel coil is 835 ℃, the coiling temperature is 645 ℃, the mechanical property meets the product quality requirement, and the continuous casting blank can be sold according to normal products.

As can be seen from the above embodiments, the utility model discloses a three-stage rolling mode of roughing mill group 3, intermediate mill group 8 and finishing mill group 13, and the setting of first heating device 6 and second heating device 11, reasonable setting rolling technology and heating temperature can reduce the wedge base that the detection caused because of roughing mill screw-down when watering the time begins and cut useless quantity to improve the yield of product; the first heating device 6 and the second heating device 11 are arranged, so that the temperature supplementing capability is improved, the first coils of steel produced at a low drawing speed at the beginning of the casting time are supplemented, the temperature of the first coils of steel meets the process temperature requirement and is normally produced, and the judgment of the first coils of steel in the casting time or the waste treatment amount is reduced; through the arrangement of the first heating device 6 and the second heating device 11, the temperature compensation capacity is increased, the temperature of low-drawing-speed production steel (such as medium-carbon steel and high-carbon steel) caused by chemical composition reasons is compensated, the temperature of the low-drawing-speed production steel meets the process temperature requirement and is normally produced, the product outline of the continuous casting and rolling production line is expanded, the problem that the product variety of the existing endless rolling continuous casting and rolling production line is limited is solved, and the market adaptability and the competitiveness of the endless rolling continuous casting and rolling production line are improved.

Finally, the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions, and all of them should be covered by the scope of the claims of the present invention.

Claims (10)

1. A hot rolling strip steel production line is characterized in that:

the device comprises a slab continuous casting machine, a rough rolling unit, a first shearing device, a first heating device, a medium rolling unit, a second heating device, a finishing rolling unit, a cooling device after rolling, a high-speed flying shear and a coiling unit which are sequentially connected through a roller way along the rolling direction;

the roughing mill group comprises two roughing mill frames which are sequentially arranged along the rolling direction;

the middle rolling mill group comprises a middle rolling mill frame.

2. A hot rolled strip production line as claimed in claim 1, characterised in that: the finishing mill group comprises 4-5 finishing mill frames which are arranged in sequence along the rolling direction.

3. The hot rolled strip production line of claim 1, wherein: and an iron scale removing device is arranged at the inlet of the finishing mill group.

4. A hot rolled strip production line as claimed in claim 3, characterised in that: the scale removing device is a high-pressure water descaling device.

5. A hot rolled strip production line as claimed in claim 1, characterised in that: and an iron scale removing device is arranged at an inlet of the roughing mill group and/or the intermediate mill group.

6. The hot rolled strip production line of claim 5, wherein: the scale removing device is any one of a high-pressure water descaling device, a rotary jet descaling device and a flame cleaning type descaling device.

7. The hot rolled strip production line of claim 1, wherein: the first shearing device is a pendulum shear, and a slab pushing and stacking device is arranged at an outlet of the first shearing device.

8. A hot rolled strip production line as claimed in claim 1, characterised in that: and a second shearing device is arranged between the middle rolling mill group and the second heating device.

9. The hot rolled strip production line of claim 8, wherein: the second shearing device is a pendulum shear or a rotary drum flying shear, and a waste removing device is arranged at an outlet of the second shearing device.

10. A hot rolled strip production line as claimed in claim 1, characterised in that: the first heating device is a longitudinal magnetic induction heating furnace; the second heating device is a transverse magnetic induction heating furnace or a longitudinal magnetic induction heating furnace.

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