RU2542049C1 - Steel rolling complex of metallurgical mini plant - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: proposed complex comprises induction smelting furnaces 2 in number multiple of 2 and at least one "ladle-furnace" unit 3. Maximum number of said units is two times as small as that of induction smelting furnaces. Continuous casting machine 4 is equipped with lift-and-turn platform for "ladle-furnace" unit 3 and device 5 for cutting of cast billets to lengths, device 6 to transfer rerolled billets to roll table of induction heater 9 and device 7 arranged in crosswise span to cool the billet and to transfer commercial billet to finished product storage. Semicontinuous rolling mill consists of at least one reduction stand 10 and at least two continuous sets of stands 12, 13. Downstream of stand 10 shears 11 are arranged to cut the rolled stock front end. Downstream of the stands, unit 14 of rolled stock heat surfacing, shears 15 to cut rolled stock over the length of refrigerator 16, shears 17 to cut rolled stock to preset lengths and device 18 to composed piles of finished products are mounted.

EFFECT: simplified design, higher efficiency of this complex.

3 cl, 1 dwg

Description

The inventive object relates to the field of metallurgy, namely to combined foundry-rolling complexes of metallurgical plants, and can be used in the production of small-grade rolled profiles of a wide assortment at a mini-metallurgical plant.

The closest in combination of features to the claimed object is a casting and rolling complex of a metallurgical mini-plant selected as a prototype, which includes a casting section consisting of a steel smelting unit including an induction furnace, an out-of-furnace steel processing unit and a steel casting unit into billets for continuous casting machine. The complex also contains a scale descaling unit, a rolling section containing a furnace for heating continuously cast billets for rolling and consisting of a draft and finishing rolling complex, a cooling and dressing unit for finished products. In this case, the steel smelting unit is made in the form of at least one induction furnace and one electric arc furnace technologically connected, and the steel casting unit into billets on a continuous casting machine is capable of simultaneously casting billets of equal cross-sections of square and / or round profile. The furnace for heating continuously cast billets for rolling is made in the form of a two-module unit with an induction and gas-fired furnace. The rolling complex contains technologically interconnected draft stands of the preliminary deformation mill, the mill with universal stands, the cross-helical rolling mill and the wire mill (application RU No. 2005129317 of 09/22/2005, publ. 27.03.07).

The claimed object and the prototype match the following essential features. Both casting and rolling complexes contain a casting section consisting of a steel smelting unit including an induction furnace, an out-of-furnace steel processing unit and a steel casting unit into billets on a continuous casting machine, as well as a rolling section with a furnace for heating continuously cast billets for rolling.

Analysis of the technical properties of the prototype, due to its features, shows that the receipt of the expected technical result when using the prototype is impeded by such reasons. The implementation of the unit for steelmaking in the form of technologically interconnected at least one induction furnace and one electric arc furnace, the unit for casting steel into billets on a continuous casting machine with the possibility of simultaneous continuous casting of billets of equal cross-sections of square and / or round profiles, the implementation of the heating unit for rolling two-module with an induction and gas-fired furnace, the implementation of the rolling complex with technologically interconnected black ovymi mill stands of the preliminary deformation, with the universal mill stands, mill helical rolling and wire mill complicates the overall design of the casting-rolling complex mini-plant. Such units are complex and expensive to operate. It is advisable to use them only in the production of homogeneous products in large batches, mainly reinforcing bars, round or square steel, and it is inappropriate to use in the production of long sections with small tonnages due to frequent downtime of the rolling mill during transshipment to change the size and grade range of profiles. In the process of operation of the casting and rolling complex according to the prototype, due to the large number of changing parameters, it is impossible to ensure the efficient production of long sections of a wide size and grade assortment in small batches.

The claimed object is based on the task of creating such a casting and rolling complex of a metallurgical mini-plant, in which improvements by introducing new elements will make it possible to achieve a technical result when using the inventive object, which consists in simplifying the design and increasing the efficiency of the casting and rolling complex of a mini-factory in production varietal profiles of a wide size and brand assortment.

The problem is solved as follows. The inventive casting and rolling complex of a metallurgical mini-factory contains a casting section, consisting of a steelmaking unit with an induction furnace, an out-of-furnace steel processing unit and a steel casting unit into billets on a continuous casting machine, as well as a rolling section with a furnace for heating continuously cast billets for rolling . A distinctive feature of the claimed object is the following. The steelmaking unit is made in the form of sequentially installed induction melting furnaces, the number of which is a multiple of two. The out-of-furnace steel processing unit contains at least one ladle-furnace installation, the maximum number of ladle-furnace installations being two times less than the number of induction melting furnaces. The unit for casting steel into billets is made in the form of a radial machine for continuous casting of billets, which is equipped with a tilt-up stand for the ladle of the “ladle-furnace” installation. The furnace for heating continuously cast billets for rolling is made in the form of an induction heating unit, which is equipped with a loading roller table. The continuous casting machine is equipped with a sequentially installed device for cutting continuously cast billets into measured lengths, a device for moving the continuous cast billet to the loading roller table of the induction heating unit and a device for cooling and transferring the continuously cast billet from the overturning refrigerator of the continuous casting machine to the finished goods warehouse. The rolling section comprises a semi-continuous rolling mill consisting of at least one crimping stand and at least two continuous groups of stands. Moreover, the first continuous group of stands during rolling consists of stands with alternating horizontal and vertical arrangement of the rolls, and the second continuous rolling group of stands stands along the rolling consists of stands with a horizontal arrangement of rolls. After the crimping stand, scissors are installed to trim the front end of the roll. After a continuous group of stands the installation of thermal hardening of rolled products, flying scissors for cutting rolled products to the length of the refrigerator, a refrigerator, scissors for cutting rolled products to measured lengths and a device for forming bundles of finished products are successively installed.

In some cases, the execution of the claimed object is characterized by such signs:

- with a production volume of 200 thousand tons of rolled products per year, the complex is equipped with four series-installed induction melting furnaces with a nominal capacity of 10 tons for steel and a ladle furnace with a maximum capacity of 20 tons of steel;

- the continuous casting machine is made of two strands and is adapted for casting a square commodity billet with a section, mainly 125 × 125 mm, and a length, mainly up to 12.0 m, of a round billet, mainly with a diameter of 125 mm, and a length, mainly up to 12.0 m, as well as a conversion blank with a cross section of mainly 125 × 125 mm and a length of mainly 3.0 m;

- the complex is equipped with a gas treatment plant with bag filters, a prefabricated dust bin and a device for pelletizing dust before it is introduced into the charge of induction melting furnaces.

When using the claimed facility, the achievement of a technical result is achieved, which consists in simplifying the design and increasing the efficiency of the casting and rolling complex of the mini-factory in the production of long sections of a wide size and grade assortment.

Between the set of essential features of the claimed object and the achieved technical result there is such a causal relationship.

The implementation of the steelmaking unit in the form of sequentially installed induction melting furnaces, the number of which is a multiple of two, and the implementation of out-of-furnace steel processing in a ladle-furnace installation, the maximum number of which is two times less than the number of induction melting furnaces, allows structurally relatively simple, using the charge only based on scrap metal and simultaneously carrying out out-of-furnace processing of steel from two induction melting furnaces in one ladle, to ensure high-quality smelting a wide assortment of steels. In addition, given that the steel smelting cycle in an induction melting furnace is twice as large as the steel processing cycle in the ladle-furnace installation, this technical solution allows us to organize a continuous steel smelting process with a maximum load of both induction melting furnaces and the installation ladle furnace. "

The implementation of the unit for casting steel into billets in the form of a radial machine for continuous casting of billets, which is equipped with a lifting and swivel stand for the ladle of the “ladle-furnace” installation and is equipped with sequentially installed device for cutting continuously cast billets into measured lengths, a device for moving continuously cast billets to the loading roller table installation of induction heating and a device for cooling and transferring continuously cast billets to the finished goods warehouse, allows it is structurally relatively simple to ensure the production of a high-quality round and square commodity billet, which is immediately sent to the finished goods warehouse, as well as a high-quality square billet, which, when hot, is sent to the loading roller table of the induction heating unit for further rolling.

The implementation of the rolling section in the form of a semi-continuous rolling mill, consisting of at least one crimping stand and at least two continuous groups of stands, and the first continuous rolling mill group consists of stands with alternating horizontal and vertical rolls, and the second continuous group of stands during rolling consists of stands with a horizontal arrangement of rolls, and after the crimping stand, scissors are installed to trim the front end of the roll, after a continuous group to a series of thermal hardening units were installed in series, flying scissors for cutting rolled products to the length of the refrigerator, a refrigerator, scissors for cutting rolled products into measured lengths and a device for forming bundles of finished products makes it possible to construct a relatively efficient production of square continuously cast billets using a minimum number of stands varietal profiles of a wide size and brand assortment with increasing yield.

Providing the casting and rolling complex of the metallurgical mini-plant with a gas treatment facility with bag filters, a prefabricated dust bin and a device for pelletizing dust before it is introduced into the charge of induction melting furnaces, improving the environmental situation, further enhances the efficiency of the casting and rolling complex by using bag dust filters in the charge of induction melting furnaces.

The optimal values of steel capacities of induction melting furnaces and a ladle of the ladle-furnace installation, sections and lengths of continuously cast square and round billets are determined on the basis of calculations based on simulation results.

The essence of the claimed object is illustrated by graphic material, which shows a block diagram of a casting and rolling complex of a metallurgical mini-plant.

The following notation is affixed to graphic materials:

1 - foundry;

2 - induction melting furnaces;

3 - installation "ladle-furnace";

4 - continuous casting machine;

5 - a device for cutting continuously cast billets into measured lengths;

6 - a device for moving continuously cast billet to the loading roller table of the induction heating installation;

7 - a device for cooling and transferring continuously cast billets to a finished goods warehouse;

8 - rolling section;

9 - installation of induction heating of billets for rolling;

10 - crimp stand;

11 - scissors for trimming the front end of the roll;

12 - a continuous group of stands with alternating horizontal and vertical rolls;

13 - a continuous group of stands with a horizontal arrangement of rolls;

14 - installation of thermal hardening of rolled products;

15 - flying scissors for cutting rolled to the length of the refrigerator;

16 - refrigerator;

17 - scissors for cutting rolled to measured lengths;

18 - a device for forming bundles of finished products;

19 - gas treatment facility;

20 - bag filters;

21 - prefabricated dust bin;

22 - a device for pelletizing dust.

In a specific embodiment, the inventive casting and rolling complex of a metallurgical mini-factory comprises a casting section 1, including a steel smelting unit, made in the form of successively installed induction melting furnaces 2, the number of which is a multiple of two, an out-of-furnace steel processing unit, which contains at least one “ladle-furnace” installation 3 and a steel casting unit into billets, which is made in the form of a radial machine for continuous casting of billets 4, which is equipped with a tilt-up stand for ladle of the ladle-furnace installation 3. The continuous casting machine 4 is equipped with a sequentially mounted device 5 for cutting continuously cast billets into measured lengths, a device 6 for moving the continuously cast billet to the loading roller table of the induction heating unit for continuous cast billets for rolling, and a device 7 for cooling and transfer of continuously cast billets to the finished goods warehouse. The rolling section 8 contains a furnace for heating continuously cast billets for rolling, made in the form of an induction heating installation 9, which is equipped with a loading roller table. The rolling section 8 contains a semi-continuous rolling mill, consisting of at least one crimping stand 10, after which shears are installed to cut the front end of the roll 11, and at least two continuous groups of stands. Moreover, the first continuous rolling group of stands 12 consists of stands with alternating horizontal and vertical arrangement of rolls, and the second continuous rolling group of stands 13 consists of stands with horizontal arrangement of rolls. After a continuous group of stands 13, the installation of thermal hardening of rolled products 14, flying scissors 15 for cutting rolled products to the length of the refrigerator, a refrigerator 16, scissors 17 for cutting rolled into measured lengths and a device for forming bundles of finished products 18 are sequentially installed.

The inventive casting and rolling complex is equipped with a gas treatment facility 19 with bag filters 20, a collecting hopper 21 for dust and a device 22 for pelletizing dust before it is introduced into the charge of induction melting furnaces 2.

With a production volume of 200 thousand tons of rolled products per year, the complex is equipped with four sequentially installed induction melting furnaces 2 with a nominal steel capacity of 10 tons, a ladle furnace 3 with a maximum steel capacity of 20 tons and a two-strand continuous casting machine, which is suitable for casting a square commodity billet with a cross-section, mainly 125 × 125 mm, and a length, mainly up to 12.0 m, of a round billet, mainly with a diameter of 125 mm, and a length, mainly up to 12.0 m, and also for casting individual billets with a section, mainly 125 × 125 mm, and a length, mainly 3.0 m.

The casting and rolling complex of the metallurgical mini-factory works like this. Scrap metal arriving at the plant must meet the requirements of the current standard. The metal scrap warehouse is located in the charge passage, where scrap metal is received, stored, stored and prepared. Steel is smelted in four series-mounted induction melting furnaces 2 of the GWE 10-6000-0.2 type with a melting mass of 10 tons. The GWE 10-6000-0.2 induction furnace is made in the form of a double-post melting furnace, which works with power distribution between the melting units. Melting units are switched on alternately according to the “melting for smelting” scheme. The duration of the heat is 80-90 minutes. Smelted in one induction furnace in a volume of 10 tons is poured into a steel casting ladle with a capacity of 20 tons. The ladle is sent to another induction furnace, where another melting is drained into the ladle in a volume of 10 tons. Then, a ladle with 20 tons of metal is fed to the ladle furnace »3, where the metal is brought to the required chemical composition and temperature. The processing time in the installation "ladle-furnace" 3 is 30-40 minutes.

A ladle with processed liquid steel is transferred to a lifting and turning stand of a two-strand continuous casting machine 4 for receiving a billet with a cross section of 125 × 125 mm and a length of 12 m, a round billet with a diameter of 125 mm and a length of 12 m, as well as a red square billet with a cross section of 125 × 125 mm and a length of 3 m. The casting speed is 4.0 m / min. After cutting into measured lengths on scissors 5, the converted square billets with a cross section of 125 × 125 mm and a length of 3 m are transferred using the device 6 to the loading roller table of the induction heating unit 9 for further rolling. Continuous cast billets cut to lengths on device 5 with a cross section of 125 × 125 mm and a length of 12 m and round billets with a diameter of 125 mm and a length of up to 12 m are cooled in device 7, and then transferred to the finished goods warehouse.

The technical and design decisions of the rolling production are based on the requirements of producing continuously cast square billets with a cross section of 125 × 125 mm of high-quality profiles of a wide size and grade assortment at minimal cost. Moreover, the design of the mill should be simple with minimal metal consumption and equipment cost.

Rolling production is represented by one high-quality semi-continuous mill 250. The initial billet is a continuously cast billet with a cross section of 125 × 125 mm and a length of 3 m. Before rolling, the billet is heated in the installation of 9 induction heating of continuously cast billets for rolling. The transfer of the workpieces from the roller table of the continuous casting machine 4 to the loading roller table of the induction heating unit 9, as well as the heated workpiece, to the rolling table of the trio stand is carried out by slappers. The main view of the garden is hot. The capacity of the induction heating installation for heating the billet for rolling is 3.0 MW, the cooling water flow rate is 20 m3 per hour, the area for the installation is 6 × 16 m. The plant productivity during hot planting is 30 t / h. The heating temperature of the workpieces is 1150 ° C.

Semi-continuous rolling mill 250 is located in one line and consists of a crimping stand 10 trio and two continuous groups of stands: rough 12 (continuous group of stands with alternating horizontal and vertical rolls) and finishing 13 (continuous group of stands with horizontal rolls). The diameter of the rolls of the trio stand is 550 mm, the barrel length is 1600 mm. The rotation frequency of the rolls is 100 rpm. Crate 10 is equipped with a lift-swing table. Tilting of peals - with rolling reinforcement. Rolling is performed without overlap. Transshipment of the crate - rolls. After stand 10 of the trio, stationary scissors are installed to trim the front end of the roll 11. The maximum roll section for cutting is 80 × 80 mm. The distance from the axis of the stand of the 10 trios to the scissors is 15 m.

Rough continuous group of stands 12 consists of six alternating horizontal and vertical stands. The distance between the axes of the stands in the group is 2000 mm. The diameter of the rolls of the first two stands of the draft group is 450 mm, the rest is 350 mm, the barrel length is 800 mm. Transshipment of stands with cassettes. Rolling in the stands of the rough group is carried out in one thread without tilting peals.

Finishing continuous group of stands 13 consists of six horizontal stands. The distance between the axes of the stands in the group is 3000 mm. The diameter of the rolls of the stands of the finishing group is 250 mm, the barrel length is 600 mm. Transshipment of stands with cassettes. Rolling in the stands of the finishing group is carried out in one or two threads with a pitching of peals of rolling reinforcement.

In roughing 12 and finishing 13 groups, rolling is carried out in a continuous mode without a loop and tension of peals in the inter-stand spaces. This mode is provided by a second-class automation system. The maximum rolling speed in the finishing stand is 10 m / s. Size control of finished products is carried out by templates by measuring samples.

Finished hire is sent to the installation 14 thermal hardening of the rental, which is located behind the finishing stand. The length of the installation is 8 m. This installation provides hardening of rolled products during rolling in one or two threads. After thermal hardening installation 14, flying scissors 15 are located for cutting the rolled products to the length of the refrigerator 16. The distance from the scissors to the refrigerator is 25 m. Next, the rolling is moved to the rack cooler 16, which is 54 × 8 m in size. Scissors 17 are installed on the discharge roller table of the refrigerator 16. for cutting rolled products into measured lengths with a cold cutting force of 160 tons. After cooling on the refrigerator 16 and cutting into measured lengths, rolled products are dumped into the pockets of the device 18 for forming bundles of finished products. Each pack of finished products is tied with manual strapping machines (not shown in the drawings). The finished package is weighed by crane weights, a tag is hung on the package and it is transported by crane to the finished product warehouse.

At the inventive foundry-rolling complex of a metallurgical mini-plant for purification of process gases generated at foundry 1 and rolling 8 sections, a gas treatment facility 19 with bag filters 20 is provided. The dust collected by bag filter 20 is sent via a conveyor system to a collecting hopper 21 for dust is pelletized in the device 22 for pelletizing dust and then taken to a steel mill for use as an additional material in the charge of induction melting furnaces 2. Iron-containing waste roduction (slag, dust) was added and kneaded into the blend for steel smelting. Also used as an additive in the mixture for steelmaking is used scrap extracted from slag, a continuous casting blank and a ladle scrap. Crushed stone and sand after processing and separation of slag are sent to consumers.

Thus, with a relatively simple design of the casting and rolling complex of the metallurgical mini-plant, highly efficient production of up to 200 thousand tons of finished products of a wide assortment and high quality with an increase of 12-18% yield, reduction in steel consumption on average by rolled products is ensured 200-289 kg / t in comparison with the production of rolled products at a metallurgical plant with a full cycle when casting steel into molds, as well as with a 20-40% reduction in the cost of fuel and energy resources. The use of continuously cast billets saves up to 170 kg of standard fuel and about 80 kWh of electricity per ton of finished steel.

Claims (3)

1. The casting and rolling complex of a metallurgical mini-factory containing a casting section, consisting of a steelmaking unit with an induction furnace, an out-of-furnace steel processing unit and a steel casting unit into billets in the form of a continuous casting machine, a rolling section with a furnace for heating continuously cast billets under rolling, characterized in that the steelmaking unit is made in the form of sequentially installed induction melting furnaces, the number of which is a multiple of two, the unit for out-of-furnace steel processing contains um, at least one ladle-furnace installation, the maximum number of ladle-furnace installations being two times less than the number of induction melting furnaces, the steel casting unit into billets is made in the form of a radial continuous casting machine, which is equipped with a lifting a rotary stand for the ladle of the "ladle-furnace" installation, while the furnace for heating continuously cast billets for rolling is made in the form of an induction heating installation, which is equipped with a loading roller table, and a radial continuous casting machine I workpieces equipped with sequentially installed device for cutting continuously cast billets into measured lengths, a device for moving continuously cast billets to the loading roller table of the induction heating unit and a device for cooling and transferring continuously cast billets to the finished goods warehouse, and the rolling section is made in the form of a semi-continuous rolling mill, consisting of at least one crimping stand and at least two continuous groups of stands, wherein during the rolling process, the continuous group of stands consists of stands with alternating horizontal and vertical arrangement of rolls, and the second continuous group of stands along the rolling consists of stands with horizontal arrangement of rolls, while scissors are installed after the crimping stand to cut the front end of the roll, after the continuous group installation of thermal hardening of rolled products, flying scissors for cutting rolled products to the length of the refrigerator, a refrigerator, scissors for cutting rolled products in m molecular length and a device for forming stacks of finished products. 2. The casting and rolling complex according to claim 1, characterized in that at a production volume of 200 thousand tons of rolled metal per year, the complex is equipped with four series-mounted induction melting furnaces with a nominal steel capacity of 10 tons and a ladle furnace with with a maximum capacity of 20 tons for steel and a double-strand continuous casting machine adapted for casting square commodity billets with a cross section of mainly 125 × 125 mm and a round billet, mainly with a diameter of 125 mm, and a length of up to 12.0 m, and also a billet with a cross-section, mainly 125 × 125 mm, and a length, mainly 3.0 m. 3. The casting and rolling complex according to claim 1, characterized in that the complex is equipped with a gas treatment plant with bag filters, a prefabricated dust bin and a device for pelletizing dust before it is introduced into the charge of induction melting furnaces.