Special-shaped steel drawing method with high safety

Abstract

The invention relates to the technical field of profile processing, and discloses a high-safety deformed steel drawing method which comprises the following steps: S1, molten steel smelting: adding deoxidation materials into molten steel to enable oxygen in steel to react with the deoxidation materials to generate a deoxidation product insoluble in the molten steel, and enabling the deoxidation product to float from the molten steel to enter slag, and meanwhile, niobium, titanium, vanadium and manganese are added into the molten steel, and the molten steel is subjected to deoxidation alloying treatment. Grain growth can be effectively inhibited when a steel billet is heated in a high-temperature section, austenite can be fully flattened without recrystallization transformation in the later rolling period, generation of fine ferrite clusters can be better facilitated, the fatigue performance can be improved, the steel has good strength and toughness, and the service life of the steel is prolonged. The process precision and the surface quality of deformed steel products can be improved, the yield and the working efficiency are improved, meanwhile, breakage in the steel drawing process can be avoided, and the steel drawing safety is improved.

Description

Technical Field

[0001] The invention relates to the technical field of profile processing, in particular to a method for drawing special-shaped steel with high safety. Background Art

[0002] With the rapid development of my country's economy, China has become the world's largest steel producer, consumer and exporter, but at the same time, the requirements for steel are becoming increasingly higher. Steel materials are gradually developing from ordinary grades to high strength, high toughness and other aspects to improve comprehensive performance.

[0003] However, due to the high strength of high-strength cold-drawn steel, it is difficult to form during the cold drawing process, and the mold is easily damaged, which reduces the process accuracy and surface quality of the product. At the same time, due to the high strength of the steel, the steel is easily broken during the cold drawing process, thereby reducing the yield rate and work efficiency. At the same time, when the steel is broken, fragments will be ejected, which can easily cause harm to the staff, resulting in low safety of steel drawing. Therefore, a high-safety special-shaped steel drawing method is proposed. Summary of the invention

[0004] 1. Technical issues to be resolved In view of the shortcomings of the prior art, the present invention provides a method for drawing special-shaped steel with high safety, which is mainly used to solve the problem that the existing steel is broken during the cold drawing process, thereby reducing the yield rate and work efficiency. At the same time, when the steel is broken, fragments will be ejected, which may easily cause harm to the staff, resulting in low safety of steel drawing.

[0005] (II) Technical solution To achieve the above object, the present invention provides the following technical solutions: A method for drawing special-shaped steel with high safety, comprising the following steps: S1: molten steel smelting, adding deoxidizing materials to the molten steel so that the oxygen in the steel reacts with these deoxidizing materials to generate deoxidizing products insoluble in the molten steel, and making them float from the molten steel into the slag, while adding niobium, titanium, vanadium and manganese metals to the molten steel to perform deoxidation and alloying treatment on the molten steel; S2: pouring, pouring the treated molten steel on a continuous casting machine to form steel, with a target superheat of 25-35°C and a casting speed of 1.4-2.2 m / min; S3: Steel treatment: After the cast steel is cooled to room temperature, the surface of the steel is polished and cleaned to remove dust and burrs on the surface, and one end of the steel is sharpened, and then the steel is soaked and cleaned with sub-acid solution; S4: Drawing, guiding the cleaned steel into the special-shaped rollers of the special-shaped movable die for rolling die drawing at a rolling start temperature of 900-950°C, a finishing mill temperature of 850-890°C, and a sizing temperature of 850-950°C; S5: Annealing, heating the drawn steel to 710-740℃, keeping it warm for 3-5h, cooling it to 650-720℃ at a rate of 6-11℃ / min, keeping it warm for 2-3h, cooling it to 200-350℃ at a rate of 22-42℃ / min, keeping it warm for 1-2h, and finally cooling it slowly to 160-190℃ before taking it out of the furnace; S6: Drawing with a special-shaped tungsten steel die, the steel material processed in S5 is introduced into the die hole of the special-shaped tungsten steel die for drawing; S7: Straightening and warehousing: straighten the special-shaped steel that has been drawn in S6, cut off the tails of both ends of the steel evenly, and obtain the special-shaped steel drawing products, which are then inspected, packaged and put into storage.

[0006] Furthermore, the deoxidizing material is any one or more of carbon powder, ferrosilicon powder, calcium carbide, aluminum powder, calcium silicon powder, carbon powder, ferrosilicon powder, calcium silicon powder and electrode powder.

[0007] On the basis of the above scheme, ultrasonic vibration is used to accelerate the cleaning during the pickling process in S2, and the temperature of the pickling solution is 20-25°C.

[0008] As a further solution of the present invention, the number of times of rolling die drawing in S3 is 3-6 times.

[0009] Furthermore, the tapping temperature of the molten steel in S1 is 1600-1650°C.

[0010] Based on the above scheme, the steps S5 and S6 are cycled 3-5 times in sequence.

[0011] As a further solution of the present invention, nitrogen is introduced during the S5 annealing process to protect the steel.

[0012] (III) Beneficial effects Compared with the prior art, the present invention provides a highly safe method for drawing special-shaped steel, which has the following beneficial effects: 1. The present invention fully exerts the effects of fine grain strengthening and precipitation strengthening by adding niobium, titanium and vanadium. Among them, vanadium and titanium are high temperature stable carbides, which can effectively inhibit the growth of grain size when the billet is heated in the high temperature section. At the same time, the addition of niobium can increase the crystallization temperature of austenite, and in the later stage of rolling, the austenite can be fully flattened without recrystallization transformation. The distorted austenite is more conducive to the generation of fine ferrite clusters in the subsequent phase transformation.

[0013] 2. The present invention adds manganese, which mainly plays the role of refining grains, thereby improving strength and increasing toughness. The present invention combines manganese and vanadium, which not only refines grains but also improves fatigue performance, so that the steel has good strength and toughness.

[0014] 3. The present invention improves the annealing process, has the characteristics of simple process and good effect, and improves the steel's smoothness and structural uniformity while ensuring the strength of the steel, thereby significantly improving the comprehensive mechanical properties of the material.

[0015] 4. The present invention can effectively improve the process accuracy and surface quality of special-shaped steel products, improve the yield rate and work efficiency, and at the same time avoid breakage during steel drawing, thereby improving the safety of steel drawing. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The present invention provides a schematic diagram of the process structure of a highly safe special-shaped steel drawing method. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Example 1 Reference Figure 1 , a highly safe special-shaped steel drawing method, comprising the following steps: S1: molten steel smelting, adding deoxidizing materials to the molten steel so that oxygen in the steel reacts with these deoxidizing materials to generate deoxidizing products insoluble in the molten steel, and making them float from the molten steel into the slag, and at the same time adding niobium, titanium, vanadium and manganese metals to the molten steel, and performing deoxidation alloying treatment on the molten steel. By adding niobium, titanium and vanadium, the effects of fine grain strengthening and precipitation strengthening are fully exerted. Among them, vanadium and titanium are high-temperature stable carbides, which can effectively inhibit the growth of grain size when the billet is heated in the high temperature section. At the same time, the addition of niobium can increase the crystallization temperature of austenite, and in the later stage of rolling, the austenite can be fully flattened without recrystallization transformation. The distorted austenite is more conducive to the generation of fine ferrite clusters in the subsequent phase transformation. By adding manganese, manganese mainly plays the role of refining grains, thereby improving strength and toughness. The combination of manganese and vanadium in the present invention can not only refine grains but also improve fatigue performance, so that the steel has good strength and toughness; S2: pouring, pouring the treated molten steel on a continuous casting machine to form steel, with a target superheat of 25°C and a casting speed of 1.4m / min; S3: Steel treatment: After the cast steel is cooled to room temperature, the surface of the steel is polished and cleaned to remove dust and burrs on the surface, and one end of the steel is sharpened, and then the steel is soaked and cleaned with sub-acid solution; S4: Drawing, guiding the cleaned steel into the special-shaped rollers of the special-shaped movable die for roller drawing at a rolling start temperature of 900°C, a finishing mill temperature of 850°C, and a sizing temperature of 850°C; S5: Annealing, heating the drawn steel to 710℃, keeping it warm for 3h, cooling it to 650℃ at a rate of 6℃ / min, keeping it warm for 2h, cooling it to 200℃ at a rate of 22℃ / min, keeping it warm for 1h, and finally slowly cooling it to 160℃ before taking it out of the furnace. By improving the annealing process, it has the characteristics of simple process and good effect. While ensuring the strength of the steel, it improves the steel's smoothness and uniformity of organization, and significantly improves the comprehensive mechanical properties of the material; S6: Drawing with a special-shaped tungsten steel die, the steel material processed in S5 is introduced into the die hole of the special-shaped tungsten steel die for drawing; S7: Straightening and warehousing. Straighten the special-shaped steel that has been drawn in S6, cut off the tails of the steel at both ends to obtain the finished special-shaped steel drawing products, and then inspect them, pack and put them into storage. This can effectively improve the process accuracy and surface quality of special-shaped steel products, improve the yield rate and work efficiency, and avoid breakage during steel drawing, thereby improving the safety of steel drawing.

[0019] In the present invention, the deoxidizing materials are carbon powder, ferrosilicon powder, calcium silicon powder, carbon powder, ferrosilicon powder, calcium silicon powder and electrode powder. Ultrasonic vibration is used to accelerate the cleaning during the pickling process in S2, the temperature of the pickling solution is 20°C, the number of roller die drawing in S3 is 3 times, the steel tapping temperature of the molten steel in S1 is 1600°C, the steps of S5 and S6 are cycled 3 times in sequence, and nitrogen is introduced during the annealing process of S5 to protect the steel.

[0020] Example 2 Reference Figure 1 , a highly safe special-shaped steel drawing method, comprising the following steps: S1: molten steel smelting, adding deoxidizing materials to the molten steel so that oxygen in the steel reacts with these deoxidizing materials to generate deoxidizing products insoluble in the molten steel, and making them float from the molten steel into the slag, and at the same time adding niobium, titanium, vanadium and manganese metals to the molten steel, and performing deoxidation alloying treatment on the molten steel. By adding niobium, titanium and vanadium, the effects of fine grain strengthening and precipitation strengthening are fully exerted. Among them, vanadium and titanium are high-temperature stable carbides, which can effectively inhibit the growth of grain size when the billet is heated in the high temperature section. At the same time, the addition of niobium can increase the crystallization temperature of austenite, and in the later stage of rolling, the austenite can be fully flattened without recrystallization transformation. The distorted austenite is more conducive to the generation of fine ferrite clusters in the subsequent phase transformation. By adding manganese, manganese mainly plays the role of refining grains, thereby improving strength and toughness. The combination of manganese and vanadium in the present invention can not only refine grains but also improve fatigue performance, so that the steel has good strength and toughness; S2: pouring, pouring the treated molten steel on a continuous casting machine to form steel, with a target superheat of 30°C and a casting speed of 2m / min; S3: Steel treatment: After the cast steel is cooled to room temperature, the surface of the steel is polished and cleaned to remove dust and burrs on the surface, and one end of the steel is sharpened, and then the steel is soaked and cleaned with sub-acid solution; S4: Drawing, the cleaned steel is guided into the special-shaped rollers of the special-shaped movable die for rolling drawing at a rolling start temperature of 930°C, a finishing mill temperature of 870°C, and a sizing temperature of 900°C; S5: Annealing, heating the drawn steel to 720℃, keeping it warm for 4h, cooling it to 700℃ at a rate of 9℃ / min, keeping it warm for 2-3h, cooling it to 300℃ at a rate of 32℃ / min, keeping it warm for 1h, and finally slowly cooling it to 175℃ before taking it out of the furnace. By improving the annealing process, it has the characteristics of simple process and good effect. While ensuring the strength of the steel, it improves the steel's smoothness and uniformity of organization, and significantly improves the comprehensive mechanical properties of the material; S6: Drawing with a special-shaped tungsten steel die, the steel material processed in S5 is introduced into the die hole of the special-shaped tungsten steel die for drawing; S7: Straightening and warehousing. Straighten the special-shaped steel that has been drawn in S6, cut off the tails of the steel at both ends to obtain the finished special-shaped steel drawing products, and then inspect them, pack and put them into storage. This can effectively improve the process accuracy and surface quality of special-shaped steel products, improve the yield rate and work efficiency, and avoid breakage during steel drawing, thereby improving the safety of steel drawing.

[0021] In the present invention, the deoxidizing materials are carbon powder, ferrosilicon powder, calcium carbide, aluminum powder, calcium silicon powder, carbon powder, ferrosilicon powder, calcium silicon powder and electrode powder. Ultrasonic vibration is used to accelerate the cleaning during the pickling process in S2, the temperature of the pickling solution is 22°C, the number of roller die drawing in S3 is 5 times, the steel tapping temperature of the molten steel in S1 is 1640°C, the steps of S5 and S6 are cycled 4 times in sequence, and nitrogen is introduced during the annealing process of S5 to protect the steel.

[0022] Example 3 Reference Figure 1 , a highly safe special-shaped steel drawing method, comprising the following steps: S1: molten steel smelting, adding deoxidizing materials to the molten steel so that oxygen in the steel reacts with these deoxidizing materials to generate deoxidizing products insoluble in the molten steel, and making them float from the molten steel into the slag, and at the same time adding niobium, titanium, vanadium and manganese metals to the molten steel, and performing deoxidation alloying treatment on the molten steel. By adding niobium, titanium and vanadium, the effects of fine grain strengthening and precipitation strengthening are fully exerted. Among them, vanadium and titanium are high-temperature stable carbides, which can effectively inhibit the growth of grain size when the billet is heated in the high temperature section. At the same time, the addition of niobium can increase the crystallization temperature of austenite, and in the later stage of rolling, the austenite can be fully flattened without recrystallization transformation. The distorted austenite is more conducive to the generation of fine ferrite clusters in the subsequent phase transformation. By adding manganese, manganese mainly plays the role of refining grains, thereby improving strength and toughness. The combination of manganese and vanadium in the present invention can not only refine grains but also improve fatigue performance, so that the steel has good strength and toughness; S2: pouring, pouring the treated molten steel into a continuous casting machine to form steel, with a target superheat of 35°C and a casting speed of 2.2 m / min; S3: Steel treatment: After the cast steel is cooled to room temperature, the surface of the steel is polished and cleaned to remove dust and burrs on the surface, and one end of the steel is sharpened, and then the steel is soaked and cleaned with sub-acid solution; S4: Drawing, the cleaned steel is guided into the special-shaped rollers of the special-shaped movable die for rolling die drawing at a rolling start temperature of 950°C, a finishing mill temperature of 890°C, and a sizing temperature of 950°C; S5: Annealing, heating the drawn steel to 740℃, keeping it warm for 5h, cooling it to 720℃ at a rate of 11℃ / min, keeping it warm for 3h, cooling it to 350℃ at a rate of 42℃ / min, keeping it warm for 2h, and finally slowly cooling it to 190℃ before taking it out of the furnace. By improving the annealing process, it has the characteristics of simple process and good effect. While ensuring the strength of the steel, it improves the steel's smoothness and uniformity of organization, and significantly improves the comprehensive mechanical properties of the material; S6: Drawing with a special-shaped tungsten steel die, the steel material processed in S5 is introduced into the die hole of the special-shaped tungsten steel die for drawing; S7: Straightening and warehousing. Straighten the special-shaped steel that has been drawn in S6, cut off the tails of the steel at both ends to obtain the finished special-shaped steel drawing products, and then inspect them, pack and put them into storage. This can effectively improve the process accuracy and surface quality of special-shaped steel products, improve the yield rate and work efficiency, and avoid breakage during steel drawing, thereby improving the safety of steel drawing.

[0023] In the present invention, the deoxidizing materials are carbon powder, ferrosilicon powder, calcium carbide, aluminum powder, calcium silicon powder and carbon powder. Ultrasonic vibration is used to accelerate the cleaning during the pickling process in S2, the temperature of the pickling solution is 25°C, the number of roller die drawing in S3 is 6 times, the steel tapping temperature of the molten steel in S1 is 1650°C, the steps of S5 and S6 are cycled 5 times in sequence, and nitrogen is introduced during the annealing process of S5 to protect the steel.

[0024] In the description of this article, it should be noted that relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

Claims

1. A method for drawing special-shaped steel with high safety, characterized in that: The following steps are involved: S1: molten steel smelting, adding deoxidizing materials to the molten steel so that the oxygen in the steel reacts with these deoxidizing materials to generate deoxidizing products insoluble in the molten steel, and making them float from the molten steel into the slag, while adding niobium, titanium, vanadium and manganese metals to the molten steel to perform deoxidation and alloying treatment on the molten steel; S2: pouring, pouring the treated molten steel on a continuous casting machine to form steel, with a target superheat of 25-35°C and a casting speed of 1.4-2.2 m / min; S3: Steel treatment: After the cast steel is cooled to room temperature, the surface of the steel is polished and cleaned to remove dust and burrs on the surface, and one end of the steel is sharpened, and then the steel is soaked and cleaned with sub-acid solution; S4: Drawing, guiding the cleaned steel into the special-shaped rollers of the special-shaped movable die for rolling die drawing at a rolling start temperature of 900-950°C, a finishing mill temperature of 850-890°C, and a sizing temperature of 850-950°C; S5: Annealing, heating the drawn steel to 710-740℃, keeping it warm for 3-5h, cooling it to 650-720℃ at a rate of 6-11℃ / min, keeping it warm for 2-3h, cooling it to 200-350℃ at a rate of 22-42℃ / min, keeping it warm for 1-2h, and finally cooling it slowly to 160-190℃ before taking it out of the furnace; S6: Drawing with a special-shaped tungsten steel die, the steel material processed in S5 is introduced into the die hole of the special-shaped tungsten steel die for drawing; S7: Straightening and warehousing: straighten the special-shaped steel that has been drawn in S6, cut off the tails of both ends of the steel evenly, and obtain the special-shaped steel drawing products, which are then inspected, packaged and put into storage.

2. A highly safe special-shaped steel drawing method according to claim 1, characterized in that: The deoxidizing material is any one or more of carbon powder, ferrosilicon powder, calcium carbide, aluminum powder, calcium silicon powder, carbon powder, ferrosilicon powder, calcium silicon powder and electrode powder.

3. A highly safe special-shaped steel drawing method according to claim 1, characterized in that: In the pickling process in S2, ultrasonic vibration is used to accelerate the cleaning, and the temperature of the pickling solution is 20-25°C.

4. A highly safe special-shaped steel drawing method according to claim 1, characterized in that: The number of times of rolling die drawing in S3 is 3-6 times.

5. A highly safe special-shaped steel drawing method according to claim 1, characterized in that: The tapping temperature of the molten steel in S1 is 1600-1650°C.

6. A highly safe special-shaped steel drawing method according to claim 1, characterized in that: The steps of S5 and S6 are cycled 3-5 times in sequence.

7. A highly safe special-shaped steel drawing method according to claim 6, characterized in that: During the S5 annealing process, nitrogen is introduced to protect the steel.

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