阅读说明：本技术 一种钢水的冶炼控制方法 (Smelting control method of molten steel ) 是由 安超 李辉 艾天意 陈爱军 李利杰 张普 王志刚 关震 于 2021-07-28 设计创作，主要内容包括：本发明公开了一种钢水的冶炼控制方法,属于精炼工艺技术领域,包括：获取转炉出钢钢水的第一碳含量；对精炼到站所述钢水进行定温和第一定氧,得到进站温度和第一氧含量；根据所述第一碳含量、所述进站温度和所述第一氧含量,判断是否需要对精炼到站所述钢水进行第一吹氧脱碳；若是,根据所述第一碳含量和所述第一氧含量,计算获得精炼到站所述钢水的第一脱碳吹氧量；根据所述第一脱碳吹氧量,对精炼到站所述钢水进行第一吹氧脱碳；通过第一碳含量、进站温度和第一氧含量,判断钢水精炼到站阶段时是否需要进行吹氧脱碳,并计算得到吹氧脱碳的脱碳吹氧量,准确控制精炼阶段的氧含量,精简精炼阶段的真空脱碳处理所需步骤,缩短真空脱碳处理周期。(The invention discloses a molten steel smelting control method, which belongs to the technical field of refining processes and comprises the following steps: obtaining a first carbon content of molten steel tapped from a converter; performing constant temperature and first constant oxygen on the molten steel refined to the station to obtain the station entering temperature and the first oxygen content; judging whether first oxygen blowing decarbonization needs to be carried out on the molten steel refined to the station according to the first carbon content, the station entering temperature and the first oxygen content; if yes, calculating and obtaining a first decarburization oxygen blowing amount of the molten steel refined to the station according to the first carbon content and the first oxygen content; according to the first decarburization oxygen blowing amount, carrying out first oxygen blowing decarburization on the molten steel refined to the station; through the first carbon content, the station entering temperature and the first oxygen content, whether oxygen blowing decarburization needs to be carried out when the molten steel is refined to the station stage is judged, the decarburization oxygen blowing amount of the oxygen blowing decarburization is calculated, the oxygen content of the refining stage is accurately controlled, steps required by vacuum decarburization processing in the refining stage are simplified, and the vacuum decarburization processing period is shortened.)

1. A method for controlling smelting of molten steel, characterized by comprising:

obtaining a first carbon content of molten steel tapped from a converter;

performing constant temperature and first constant oxygen on the molten steel refined to the station to obtain the station entering temperature and the first oxygen content;

obtaining the target oxygen content of the molten steel after vacuum decarburization treatment;

judging whether first oxygen blowing decarbonization needs to be carried out on the molten steel refined to the station according to the first carbon content, the station entering temperature, the first oxygen content and a target oxygen content;

if yes, calculating and obtaining a first decarburization oxygen blowing amount of the molten steel refined to the station according to the first carbon content, the first oxygen content and the target oxygen content;

and according to the first decarburization oxygen blowing amount, carrying out first oxygen blowing decarburization on the molten steel refined to the station.

2. The method of claim 1, wherein the determining whether first oxygen decarburization of the molten steel to a refining station is required based on the first carbon content, the inbound temperature, the first oxygen content, and a target oxygen content comprises: setting a target temperature after the first oxygen blowing decarburization is finished according to the first carbon content, the station entering temperature, the first oxygen content and the target oxygen content, and judging whether the first oxygen blowing decarburization needs to be carried out on the molten steel refined to the station or not according to a temperature difference value between the target temperature and the station entering temperature and a first oxygen content difference value between the first oxygen content and the target oxygen content;

and if the temperature difference and the first oxygen content difference are both larger than zero, performing first oxygen blowing decarburization on the molten steel which is refined to the station.

3. The smelting control method according to claim 1, wherein the calculation formula of the first decarburization oxygen blowing amount is:

the first decarburization blowing oxygen amount (first carbon content 0.9+ target oxygen content — first oxygen content) 0.4.

4. The method of claim 1, wherein the calculating, based on the first carbon content and the first oxygen content, a decarburization oxygen amount of the molten steel that is refined to a station includes:

carrying out vacuum decarburization treatment on the molten steel;

in the early stage of the vacuum decarburization treatment, carrying out second oxygen determination on the molten steel to obtain a second oxygen content;

judging whether second oxygen blowing decarburization is needed to be carried out on the molten steel in the vacuum decarburization treatment or not according to the second oxygen content;

if so, calculating a second decarburization oxygen blowing amount of the second oxygen blowing decarburization according to the second oxygen content and the target oxygen content.

5. The method of claim 4, wherein the determining whether the second oxygen decarburization of the molten steel at the early stage of the vacuum decarburization processing is required based on the second oxygen content includes: and judging whether second oxygen blowing decarburization is needed or not according to the second oxygen content and a second oxygen content difference value of the second oxygen content and the target oxygen content.

6. The smelting control method according to claim 4, wherein the second decarburization oxygen blowing amount is calculated by the formula:

the second decarburization blowing oxygen amount (target oxygen content — second oxygen content) was 0.4.

7. The method of claim 4, wherein the preceding stage of the vacuum decarburization processing is 5 to 10min from the start of the vacuum decarburization processing.

8. The smelting control method according to claim 4, wherein the target oxygen content is 280ppm to 350ppm when the molten steel is an IF steel molten steel.

9. The method of claim 4, wherein the second decarburization processing is performed on the molten steel before the vacuum decarburization processing by the second oxygen blowing amount, and thereafter, the method comprises:

acquiring a second carbon content of the molten steel at the end of decarburization treatment in vacuum decarburization treatment;

judging whether the carbon of the molten steel at the final stage of decarburization treatment needs to be adjusted or not according to the second carbon content;

if yes, calculating and obtaining the carbon regulation amount of the molten steel at the end of decarburization treatment according to the second carbon content;

and obtaining the carbon alloy addition amount of the molten steel at the final stage of the vacuum decarburization treatment according to the carbon adjustment amount.

10. The smelting control method according to claim 5, wherein the end of the decarburization processing is 0.5 to 2min before the end of the decarburization processing.

Technical Field

The invention belongs to the technical field of steel preparation, and particularly relates to a molten steel smelting control method.

Background

IF steel is also called interstitial-free steel, since the content of C, N is low and C, N atoms in the steel are fixed into carbide and nitride by adding a certain amount of Ti and Nb, so that interstitial atoms do not exist in the steel, the IF steel is called interstitial-free steel.

At present, in the field, most of the IF steel is prepared by adjusting the carbon content to stabilize the IF steel, and the adjustment of the carbon content generally adopts multiple decarburization in a refining stage, so that the defect that the vacuum decarburization treatment period in the refining stage is too long in the whole process is caused.

Disclosure of Invention

The application provides a molten steel smelting control method, which aims to solve the technical problem of overlong vacuum decarburization treatment period in a refining stage.

A method of controlling smelting of molten steel, the method comprising:

obtaining a first carbon content of molten steel tapped from a converter;

performing constant temperature and first constant oxygen on the molten steel refined to the station to obtain the station entering temperature and the first oxygen content;

obtaining the target oxygen content of the molten steel after vacuum decarburization treatment;

judging whether first oxygen blowing decarbonization needs to be carried out on the molten steel refined to the station according to the first carbon content, the station entering temperature, the first oxygen content and a target oxygen content;

if yes, calculating and obtaining a first decarburization oxygen blowing amount of the molten steel refined to the station according to the first carbon content, the first oxygen content and the target oxygen content;

and according to the first decarburization oxygen blowing amount, carrying out first oxygen blowing decarburization on the molten steel refined to the station.

Optionally, the determining whether the first oxygen decarburization needs to be performed on the molten steel refined to the station according to the first carbon content, the station entering temperature, the first oxygen content and the target oxygen content includes: setting a target temperature after the first oxygen blowing decarburization is finished according to the first carbon content, the station entering temperature, the first oxygen content and the target oxygen content, and judging whether the first oxygen blowing decarburization needs to be carried out on the molten steel refined to the station or not according to a temperature difference value between the target temperature and the station entering temperature and a first oxygen content difference value between the first oxygen content and the target oxygen content;

and if the temperature difference and the first oxygen content difference are both larger than zero, performing first oxygen blowing decarburization on the molten steel which is refined to the station.

Optionally, the calculation formula of the first decarburization oxygen blowing amount is as follows:

the first decarburization blowing oxygen amount (first carbon content 0.9+ target oxygen content — first oxygen content) 0.4,

wherein, the target oxygen content refers to the oxygen content of the molten steel required after vacuum decarburization treatment, and can be 300ppm according to the conventional decarburization requirement;

0.9 and 0.4 are the decarburization reaction coefficients in the refining stage.

Optionally, calculating a first decarburization oxygen blowing amount of the molten steel refined to the station according to the first carbon content, the first oxygen content and the target oxygen content, and including:

carrying out vacuum treatment on the molten steel;

obtaining the target oxygen content in the early stage of vacuum decarburization treatment;

in the early stage of the vacuum decarburization treatment, carrying out second oxygen determination on the molten steel to obtain a second oxygen content;

judging whether second oxygen blowing decarburization is needed to be carried out on the molten steel in the vacuum decarburization treatment or not according to the second oxygen content;

if so, calculating a second decarburization oxygen blowing amount of the second oxygen blowing decarburization according to the second oxygen content and the target oxygen content.

Optionally, the determining whether to perform second oxygen decarburization on the molten steel at the earlier stage of the vacuum decarburization treatment according to the second oxygen content includes: and judging whether second oxygen blowing decarburization is needed or not according to the second oxygen content and a second oxygen content difference value of the second oxygen content and the target oxygen content.

Optionally, the calculation formula of the second decarburization oxygen blowing amount is as follows:

the second decarburization blowing oxygen amount (target oxygen content-second oxygen content) is 0.4,

wherein, the target oxygen content refers to the oxygen content of the molten steel required after vacuum decarburization treatment, and can be 300ppm according to the conventional decarburization requirement;

0.4 is the decarburization reaction coefficient in the refining stage.

Optionally, the early stage of the vacuum decarburization treatment is 5-10min of the timing when the vacuum decarburization treatment is started.

Optionally, when the molten steel is molten steel of IF steel, the target oxygen content is 280ppm to 350 ppm.

Optionally, after performing second oxygen decarburization on the molten steel at the earlier stage of the vacuum decarburization treatment according to the second decarburization oxygen blowing amount, the method includes:

acquiring a second carbon content of the molten steel at the final stage of decarburization treatment of vacuum decarburization treatment;

judging whether the carbon of the molten steel at the final stage of decarburization treatment needs to be adjusted or not according to the second carbon content;

if yes, calculating and obtaining the carbon regulation amount of the molten steel at the end of decarburization treatment according to the second carbon content;

and obtaining the carbon alloy addition amount of the molten steel at the final stage of the vacuum decarburization treatment according to the carbon adjustment amount.

Optionally, the final stage of the decarburization treatment is 0.5 to 2min before the end of the decarburization treatment.

One or more technical solutions in the embodiments of the present application have at least the following technical effects or advantages:

the embodiment of the application provides a molten steel smelting control method, which comprises the following steps: obtaining a first carbon content of molten steel tapped from a converter; performing constant temperature and first constant oxygen on the molten steel refined to the station to obtain the station entering temperature and the first oxygen content; obtaining the target oxygen content of the molten steel after vacuum decarburization treatment; judging whether first oxygen blowing decarbonization needs to be carried out on the molten steel refined to the station according to the first carbon content, the station entering temperature, the first oxygen content and a target oxygen content;

if yes, calculating and obtaining a first decarburization oxygen blowing amount of the molten steel refined to the station according to the first carbon content, the first oxygen content and the target oxygen content;

and according to the first decarburization oxygen blowing amount, carrying out first oxygen blowing decarburization on the molten steel refined to the station.

In this application, through first carbon content, the entering temperature, first oxygen content and target oxygen content, judge whether the molten steel is refined to the station stage when need carry out the oxygen blowing decarbonization, and calculate the decarbonization oxygen blowing volume that obtains the oxygen blowing decarbonization, thereby the oxygen content in accurate control refining stage, because the decarbonization is with carbon and oxygen reaction, consequently the oxygen content in control refining stage just can accurate control enter into the carbon content in the molten steel in refining stage, avoid carbon content too high or low and need many times transfer carbon operation, thereby retrench the required step of vacuum decarburization processing in refining stage, shorten vacuum decarburization processing cycle.

The foregoing description is only an overview of the technical solutions of the present invention, and the embodiments of the present invention are described below in order to make the technical means of the present invention more clearly understood and to make the above and other objects, features, and advantages of the present invention more clearly understandable.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention.

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

FIG. 1 is a schematic flow chart of a molten steel smelting control method according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In order to solve the technical problems, the general idea of the embodiment of the application is as follows:

in the IF steel smelted by the refining stage (RH) process, 14 steel types such as wide SDC06 and BH steel which have upper and lower limit requirements for judging carbon content exist, the carbon content needs to be reduced to a certain value (below 10 ppm) through decarburization reaction in the smelting process, and then special medium-carbon ferromanganese with relatively stable carbon content is added for carbon regulation operation, so that the carbon content reaches the target value requirement.

The carburetion amount of the special medium carbon ferromanganese is basically stable, but the decarburization effect in the RH process smelting is unstable, multiple sampling detection needs to be carried out in the deoxidation alloying stage, and the carbon regulation operation is carried out after a detected result is obtained, so that the vacuum decarburization treatment period in the RH process is influenced, the whole vacuum decarburization treatment period is too long, and the final steel performance is influenced.

As shown in fig. 1, in an embodiment of the present application, there is provided a method for controlling smelting of molten steel, including:

s1, obtaining a first carbon content of molten steel tapped from a converter;

s2, performing constant temperature and first constant oxygen on the molten steel refined to the station to obtain the station entering temperature and the first oxygen content;

s3, obtaining the target oxygen content of the molten steel subjected to vacuum decarburization treatment;

s4, judging whether first oxygen blowing decarbonization needs to be carried out on the molten steel refined to the station according to the first carbon content, the station entering temperature and the first oxygen content;

as an optional embodiment, the determining whether the first oxygen decarburization needs to be performed on the molten steel refined to the station according to the first carbon content, the station entering temperature and the first oxygen content includes: setting a target temperature after the first oxygen blowing decarburization is finished according to the first carbon content, the station entering temperature, the first oxygen content and the target oxygen content, and judging whether the first oxygen blowing decarburization needs to be carried out on the molten steel refined to the station or not according to a temperature difference value between the target temperature and the station entering temperature and a first oxygen content difference value between the first oxygen content and the target oxygen content;

and if the temperature difference and the first oxygen content difference are both larger than zero, performing first oxygen blowing decarburization on the molten steel which is refined to the station.

According to the method, the necessity of first oxygen blowing decarburization is accurately judged by adopting a temperature difference value and a first oxygen content difference value, the basis of accurate judgment of oxygen blowing decarburization is provided, meanwhile, according to the size of the temperature difference value, the time period of the oxygen blowing lance is downwards blown when the first oxygen blowing decarburization is carried out can be estimated, if the temperature difference value is larger, the oxygen blowing lance is downwards blown in advance, if the temperature difference value is smaller, the oxygen blowing lance is downwards blown according to the program criterion point, so that the time of vacuum refining treatment is shortened, the accurate control of decarburization of molten steel in a refining stage is realized, unnecessary steps of vacuum decarburization treatment in the refining stage are reduced, and the period of vacuum decarburization treatment is shortened;

if yes, calculating and obtaining a first decarburization oxygen blowing amount of the molten steel refined to the station according to the first carbon content and the first oxygen content;

if not, executing the next step;

according to the first decarburization oxygen blowing amount, carrying out first oxygen blowing decarburization on the molten steel refined to the station;

as an alternative embodiment, the first decarburization blowing oxygen amount is calculated by the following formula:

the first decarburization blowing oxygen amount (first carbon content 0.9+ target oxygen content — first oxygen content) 0.4,

wherein, the target oxygen content refers to the oxygen content of the molten steel required after vacuum decarburization treatment, and can be 300ppm according to the conventional decarburization requirement;

0.9 and 0.4 are the decarburization reaction coefficients in the refining stage.

In the application, the oxygen blowing amount of the first oxygen blowing decarburization required by the molten steel is accurately calculated through the first decarburization oxygen blowing amount, and carbon and oxygen in the molten steel are removed in a reaction manner in the decarburization process, so that the carbon content of the molten steel in a refining stage can be accurately controlled through the first decarburization oxygen blowing amount, the carbon adjusting times of vacuum decarburization treatment in a subsequent refining stage are reduced, and the vacuum decarburization treatment period is shortened;

s5, carrying out vacuum decarburization treatment on the molten steel;

s6, obtaining the target oxygen content in the early stage of vacuum decarburization treatment;

s7, performing second oxygen determination on the molten steel in the early stage of the vacuum decarburization treatment to obtain a second oxygen content;

s8, judging whether second oxygen blowing decarburization is needed to be carried out on the molten steel in the vacuum decarburization treatment or not according to the second oxygen content;

as an optional embodiment, the determining whether the second oxygen decarburization of the molten steel before the vacuum decarburization treatment is required according to the second oxygen content includes: and judging whether second oxygen blowing decarburization is needed or not according to the second oxygen content and a second oxygen content difference value of the second oxygen content and the target oxygen content.

According to the method, the necessity of second oxygen blowing decarburization is accurately judged by adopting the second oxygen content difference, so that the basis of accurate judgment of the second oxygen blowing decarburization is provided, the accurate control of the initial carbon content of the molten steel in a refining stage is realized, the carbon adjusting times in vacuum decarburization treatment in the refining stage are reduced, and the vacuum decarburization treatment period is shortened;

if so, calculating a second decarburization oxygen blowing amount of the second oxygen blowing decarburization according to the second oxygen content and the target oxygen content;

if not, performing the next operation;

as an alternative embodiment, the second decarburization blowing oxygen amount is calculated by the following formula:

the second decarburization blowing oxygen amount (target oxygen content-second oxygen content) is 0.4,

wherein, the target oxygen content refers to the oxygen content of the molten steel required after vacuum decarburization treatment, and can be 300ppm according to the conventional decarburization requirement;

0.4 is the decarburization reaction coefficient in the refining stage;

in the application, the oxygen blowing amount of the second oxygen blowing decarburization required by the molten steel is accurately calculated through the second decarburization oxygen blowing amount, and carbon and oxygen in the molten steel are removed through reaction in the decarburization process, so that the carbon content of the molten steel in the refining stage can be accurately controlled through the second decarburization oxygen blowing amount, the carbon adjusting times of vacuum decarburization treatment in the subsequent refining stage are reduced, and the vacuum decarburization treatment period is shortened;

in an optional embodiment, the early stage of the vacuum decarburization treatment is 5-10min of the timing when the vacuum decarburization treatment is started;

in the 5 th-10 th min of the timing at the beginning, the oxygen in the refining stage is completely diffused, and the fully diffused oxygen stably exists in the low-pressure environment due to the vacuum low-pressure environment, so that the measured oxygen activity data is most accurate, and the carbon content in the molten steel can be effectively controlled; when the time range is too long, the whole process consumes a long time due to sufficient oxygen diffusion, so that the vacuum period is prolonged; when the time range is too short, because the oxygen is not fully diffused and is not uniformly distributed, the measurement results are different, the oxygen activity measurement is inaccurate, the subsequent second oxygen blowing decarburization judgment is influenced, the oxygen introduced by the second oxygen blowing decarburization is too much or too little, the carbon removal in the reaction decarburization stage is too much or too little, the carbon content is unstable, the process steps are required to be added for stabilization, and the vacuum decarburization treatment period in the refining stage is prolonged;

as an optional embodiment, when the molten steel is molten steel of IF steel, the target oxygen content is 280-350 ppm;

in the application, the purpose of the target oxygen content of 280-350ppm is that the oxygen activity in the value range can ensure that the carbon content in the molten steel reaches the standard level; when the value range is too large, the adverse effect is that when the aluminum product is used for deoxidation alloying, because the target oxygen content is too large, more aluminum oxide inclusions are generated in the alloying stage, and the quality of refined molten steel is influenced; when the value range is too small, the oxygen activity of the vacuum decarburization treatment is low, the decarburization reaction is not facilitated, the decarburization time is prolonged, and the vacuum decarburization treatment period is prolonged;

s9, acquiring a second carbon content of the molten steel at the last stage of decarburization treatment in vacuum decarburization treatment;

s10, judging whether carbon adjustment needs to be carried out on the molten steel at the final stage of decarburization treatment or not according to the second carbon content;

if yes, calculating and obtaining the carbon regulation amount of the molten steel at the end of decarburization treatment according to the second carbon content;

according to the carbon adjustment amount, obtaining the carbon alloy addition amount of the molten steel at the last stage of vacuum decarburization treatment;

if not, adding other needed alloys for alloying, and then finishing the refining stage.

Carbon alloys herein include, but are not limited to, medium carbon ferromanganese, low carbon ferromanganese, and medium low carbon ferromanganese.

In an optional embodiment, the end of the decarburization treatment is 0.5 to 2min before the end of the decarburization treatment.

The sampling analysis of the carbon content within 0.5-2min before the decarburization treatment is finished has the effect that the carbon content in the molten steel is stable, so that the carbon content data is more accurate, and the carbon content in the molten steel can be accurately determined; when the time range is too long, the reaction decarburization is not finished, the carbon content is unstable, the measured carbon content data is inaccurate, and the subsequently added medium carbon ferromanganese content is too much or too little, so that the carbon content in the obtained steel product is too much or too little, the stable carbon content in the subsequent step needs to be increased, and the vacuum decarburization treatment period is prolonged; when the time range is too short, the reaction decarburization is about to be finished, the carbon content of steel cannot be adjusted in time, and the performance of the steel is influenced.

As an optional embodiment, the alloy raw materials and the equipment are subjected to pre-purification treatment while the first carbon content of the molten steel tapped from the converter is obtained, and the equipment comprises: and (4) carrying out discharging inspection on the alloy raw materials, screening out impurities and cleaning the equipment.

In this application, through preliminary purification treatment alloy raw materials and equipment, get rid of the carbonaceous impurity in the alloy raw materials to simultaneously with equipment clean up, prevent the interference of carbonaceous impurity, regulation and control carbon impurity that can be comprehensive.

As an alternative embodiment, the pre-vacuum decarburization treatment is carried out between a constant temperature and a first constant oxygen, which comprises the following steps: when the molten steel is refined to a station, the refining equipment is vacuumized, and the vacuum degree is controlled to be reduced by 30-50%.

In the application, the effect of ensuring that the vacuum degree is reduced by 30-50 percent is to reduce the initial vacuum degree in refining equipment firstly, so that the feeding is convenient, and because the vacuum degree is reduced, the resistance of gas generated by molten steel in the first oxygen blowing decarbonization stage is reduced, so that the diffusion speed is increased, the vacuum degree reduction speed is accelerated, and the vacuum decarbonization treatment period can be shortened; when the range is too large, namely the vacuum degree is reduced too much, the vacuum degree after the pre-vacuum decarburization treatment is small, the system pressure is strong, the vacuum condition can not be ensured to maintain molten steel refining, the gas diffusion speed is inhibited, the removal of carbon in steel is influenced, the decarburization step is prolonged, and the vacuum decarburization treatment period is further prolonged; when the range is too small, namely the vacuum degree is reduced too low, the vacuum degree of the pre-vacuum decarburization treatment is large, the system pressure is small, at the moment, the gas diffusion speed in the molten steel refining process is too high, the carbon content in the molten steel is too low, the step needs to be added to supplement the too low carbon content, and the vacuum decarburization treatment period is prolonged.

As an alternative embodiment, the bin punching operation is performed at the beginning of the vacuum decarburization treatment, and comprises the following steps:

100kg-200kg of scrap steel is used for flushing a blanking channel from a high-level bin.

In the application, 100-200kg of scrap steel is used for removing alloy impurities in an alloy blanking channel, so that the cleanliness of the blanking channel is ensured, most of the scrap steel has enough hardness, impurities difficult to remove in the blanking channel can be removed, even if the scrap steel has part of residual, the scrap steel can be mixed with molten steel, and carbon content data can be adjusted through first oxygen determination and second oxygen determination and then through first oxygen blowing decarburization and second oxygen blowing decarburization.

Example 1

Judging that first oxygen blowing decarburization, second oxygen blowing decarburization and carbon regulation are needed;

the molten steel is IF molten steel, and the value of the target oxygen content is 320 ppm;

the early stage of the vacuum decarburization treatment is the 7 th min timed when the vacuum decarburization treatment starts;

the final stage of the vacuum decarburization treatment is 1min before the vacuum decarburization treatment is finished;

the pre-vacuum decarburization treatment comprises the following steps: when the molten steel is refined to a station, vacuumizing refining equipment, and controlling the vacuum degree to be reduced by 40 percent, wherein the vacuum degree is specifically changed from 100kPa to 60 kPa;

the bin punching operation comprises the following steps: when the vacuum decarburization treatment is started, 150kg of steel scrap is discharged from the head bin, and a blanking channel is flushed.

Example 2

Judging that first oxygen blowing decarburization, second oxygen blowing decarburization and carbon regulation are needed;

the molten steel is IF molten steel, and the value of the target oxygen content is 250 ppm;

the early stage of the vacuum decarburization treatment is 5min timed when the vacuum decarburization treatment is started;

the final stage of the vacuum decarburization treatment is 0.5min before the vacuum decarburization treatment is finished;

the pre-vacuum decarburization treatment comprises the following steps: when the molten steel is refined to a station, vacuumizing refining equipment, and controlling the vacuum degree to be reduced by 30 percent, wherein the vacuum degree is specifically reduced from 100kPa to 70 kPa;

the bin punching operation comprises the following steps: when the vacuum decarburization treatment is started, 100kg of steel scraps are sent out from a high-level bin to flush a blanking channel,

the rest of the procedure and the recipe were the same as in example 1.

Example 3

Judging that first oxygen blowing decarburization, second oxygen blowing decarburization and carbon regulation are needed;

the molten steel is IF molten steel, and the value of the target oxygen content is 350 ppm;

the early stage of the vacuum decarburization treatment is the 10 th min timed when the vacuum decarburization treatment starts;

the final stage of the vacuum decarburization treatment is 5min before the vacuum decarburization treatment is finished;

the pre-vacuum decarburization treatment comprises the following steps: when the molten steel is refined to a station, vacuumizing refining equipment, and controlling the vacuum degree to be reduced by 50 percent, wherein the vacuum degree is specifically reduced from 100kPa to 50 kPa;

the bin punching operation comprises the following steps: at the beginning of the vacuum decarburization treatment, 200kg of scrap steel was discharged from the head room to flush the blanking passage, and the rest of the procedure and the recipe were the same as those in example 1.

Example 4

Judging that first oxygen blowing decarburization and carbon regulation are needed;

the pre-vacuum decarburization treatment comprises the following steps: when the molten steel is refined to a station, vacuumizing refining equipment, and controlling the vacuum degree to be reduced by 30 percent, wherein the vacuum degree is specifically reduced from 100kPa to 70 kPa;

the bin punching operation comprises the following steps: at the beginning of the vacuum decarburization treatment, 100kg of scrap steel was discharged from the head room to flush the discharge passage, and the rest of the procedure and the recipe were the same as those in example 1.

Example 5

Judging that second oxygen blowing and carbon regulation are needed;

the pre-vacuum decarburization treatment comprises the following steps: when the molten steel is refined to a station, vacuumizing refining equipment, and controlling the vacuum degree to be reduced by 50 percent, wherein the vacuum degree is specifically reduced from 100kPa to 50 kPa;

the bin punching operation comprises the following steps: at the beginning of the vacuum decarburization treatment, 200kg of scrap steel was discharged from the head room to flush the blanking passage, and the rest of the procedure and the recipe were the same as those in example 1. .

Comparative example 1

The first oxygen determination and first oxygen blowing decarburization are not adopted, and the rest of the steps and the formula are the same as those of the example 1.

Comparative example 2

The second oxygen determination and the second oxygen blowing decarburization were not carried out, and the other steps and the recipe were the same as in example 1.

Comparative example 3

The first oxygen determination and the first oxygen blowing were not used for decarburization, the second oxygen determination and the second oxygen blowing were not used for decarburization, and the other steps and the recipe were the same as those of example 1.

Comparative example 4

The procedure and formulation were the same as in example 1 except that no carbon adjustment was used.

Related experiments:

the IF steels obtained in examples 1 to 5 and comparative examples 1 to 4 were examined and the results are shown in Table 1.

The related test method comprises the following steps:

the method for testing the carbon content of the IF steel comprises the following steps: sampling by using a sampler, sending the sampled sample to a laboratory, and performing component analysis by using a spectral analysis instrument;

the vacuum decarburization treatment period test method comprises the following steps: the timing is started when the vacuum decarburization processing is started, and the timing is stopped after the vacuum decarburization processing is finished.

TABLE 1

Specific analysis of table 1:

the content of the IF steel is the residual carbon content in the prepared IF steel, and when the carbon content is too high, the hardness and the strength of the steel are too high, and the toughness and the plasticity are reduced; when the carbon content is too low, the hardness and strength of the steel are too low, and the toughness and plasticity are improved.

The vacuum decarburization period refers to the time required for vacuum decarburization in the refining stage, and is the whole process of the refining stage of molten steel because air interference needs to be prevented in the vacuum atmosphere; when the vacuum decarburization treatment period is too long, carbon in molten steel is excessively reacted, so that the carbon content of the prepared steel is low; when the vacuum decarburization treatment period is too short, carbon in molten steel is insufficiently reacted, so that the carbon content of the prepared steel is high.

From the data of examples 1-5 in Table 1, it can be seen that:

when it is determined that the first oxygen decarburization and the second oxygen decarburization are required, the value of the target oxygen content of the second oxygen decarburization can be adjusted to meet the requirements of IF steels having different carbon contents, as in examples 1 to 5.

The first oxygen decarburization conducted by the first constant oxygen operation was judged to have a large influence on the carbon content of the IF steel and the vacuum decarburization treatment period, as in examples 1 and 5.

From the data of comparative examples 1-5 in Table 1, it can be seen that:

when the first oxygen blowing decarburization and the second oxygen blowing decarburization are judged without adopting the first fixed oxygen, the period in the vacuum decarburization treatment of the whole refining stage is prolonged because the conventional detection means is concentrated in the refining stage or the later stage of the refining stage, so that the time consumption of the vacuum decarburization treatment period is prolonged, and therefore, the comparative example 3 for judging the second oxygen blowing decarburization by not adopting the first fixed oxygen has a longer vacuum decarburization treatment period; when the first oxygen decarburization and the second oxygen decarburization are not performed, the carbon content of the IF steel is too high because the decarburization is not sufficient because the carbon in the molten steel is not supplied with the secondary oxygen during the decarburization stage.

One or more technical solutions in the embodiments of the present application at least have the following technical effects or advantages:

(1) in the embodiment of the application, because two steps of oxygen determination of first fixed oxygen and second fixed oxygen are adopted for judgment, and the first decarburization oxygen blowing amount and the second decarburization oxygen blowing amount of the first decarburization oxygen blowing and the second decarburization oxygen blowing are determined, the oxygen content of the application needs to be measured twice at most, compared with the measurement of oxygen content and carbon adjustment for multiple times in the prior art, the steps of vacuum decarburization treatment in a refining stage are shortened, and the period of vacuum decarburization treatment is shortened;

(2) the bin punching operation provided by the embodiment of the application makes full use of the characteristics of the scrap steel, can clean the blanking channel of the alloying raw material, and prevents the situation that the molten steel is not fully decarburized in the later reaction decarburization stage due to the existence of redundant carbon in the environment, so that the carbon content of IF steel is unstable;

(3) although the process steps are added in the pre-vacuum decarburization treatment provided by the embodiment of the application, the vacuum degree requirement of the whole vacuum decarburization treatment can be reduced, and the period of the vacuum decarburization treatment can be obviously shortened;

(4) all the steps provided by the embodiment of the application can be integrated into a control system in the molten steel refining stage, so that intelligent treatment is realized, and the treatment time of the whole process can be further shortened.

It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The foregoing are merely exemplary embodiments of the present invention, which enable those skilled in the art to understand or practice the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.