A method for refining 1.2312 mold steel by lf

Abstract

The application discloses a LF refining method of 1.2312 die steel. The LF refining method of the 1.2312 die steel is provided, after complete reaction of deoxidization and desulfurization, the temperature of the molten steel is precisely calculated to 1620 DEG C by the relationship between total power consumption of the electric arc and the electric arc heating amount, and a calculated amount of ferrous sulfate is added to adjust the sulfur content in the molten steel, so that the purpose of precisely adjusting the sulfur content is achieved, the defect that the sulfur content is excessively adjusted by adding ferrous sulfate too early due to incomplete deoxidization and desulfurization reaction of the molten steel in the original smelting method is overcome, the subsequent sulfur content is reduced or increased, the expected effect is not achieved, the precise control of the sulfur content of the molten steel is realized, the manufacturing cost is reduced, and the smelting quality of the molten steel is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of metallurgy, in particular to a LF refining method of 1.2312 die steel. BACKGROUND

[0002] 1.2312 belongs to high-carbon sulfur-containing free-cutting alloy die steel, and the product has good mechanical processing performance and excellent polishing performance. The main application scenarios include plastic molds, mold frames of plastic and pressure casting molds, receiving sleeves, brake molds and the like. The production process of 1.2312 provided by the related technology is as follows: high-temperature molten iron of blast furnace→(mixing furnace) 120t converter smelting→LF refining→RH→slab continuous casting machine continuous casting. The component requirements are as follows: C range: 0.36%-0.41%, Si range: 0.30%-0.50%, Mn range: 1.40%-1.60%, P range: ≤0.030%, S range: 0.050%-0.100%, Cr range: 1.80%-2.00%, Mo range: 0.15%-0.23%; C internal control: 0.36%-0.40%, Si internal control: 0.35%-0.45%, Mn internal control: 1.45%-1.55%, P internal control: ≤0.28%, S internal control: 0.060%-0.90%, Cr internal control: 1.85%-1.95%, Mo internal control: 0.16%-0.20%; C target: 0.38%, Si target: 0.40%, Mn target: 1.50%, P target: ≤0.25%, S target: 0.07%, Cr target: 1.90%, Mo target: 0.17%.

[0003] In the production process of smelting 1.2312 high-carbon sulfur-containing free-cutting alloy die steel, due to the incomplete early-stage deoxidation and desulfurization reaction of the molten steel, ferrous sulfide is added too early to adjust the composition, which causes the subsequent decrease of the sulfur content and fails to achieve the expected effect, and simultaneously increases the manufacturing cost and affects the composition control precision of the molten steel. SUMMARY

[0004] The purpose of the present application is to overcome the defects of the prior art and provide a LF refining method of 1.2312 die steel.

[0005] The technical problem of the present application is solved by adopting the following technical scheme.

[0006] The present application provides a LF refining method of 1.2312 die steel, comprising the following steps:

[0007] S1: deoxidizing and alloying of the molten steel and slag washing are performed during converter tapping;

[0008] S2: sampling at the argon station;

[0009] S3: LF refining to the station, temperature measurement, and T进站 , argon is introduced, fluorite ball, low alkali slag and lime are sequentially added, and the slag is sent to the electric arc furnace, during the power supply process, the molten steel is heated to above the liquidus temperature of the steel type + 80 DEG C, and the alloy is added to adjust the C, Si, Mn, Cr, Mo content in the molten steel;

[0010] S4: accurately calculate the temperature of the molten steel when the temperature of the molten steel is heated to 1620 DEG C by the relationship between the total power consumption of the electric arc and the heating amount of the electric arc, sample 1 is taken, and W[C] 样1 %, W[Si] 样1 %, W[Mn] 样1 %, W[S]%, W[Cr] 样1 %, W[Mo] 样1 %, slag, TFe%, MnO% and R are obtained;

[0011] S5: according to W[C] 样1 %, W[Si] 样1 %, W[Mn] 样1 %, W[Cr] 样1 %, W[Mo] 样1 %, the amount of alloy added is calculated, and the chemical composition of each element is adjusted to the target value, and according to W[S] 样1 % in sample 1 and TFe%, MnO%, R, the amount of ferrous sulphur added is calculated, and the chemical composition of S element is adjusted to the target value;

[0012] S6: continue to supply power to heat to the required temperature of the RH, measure the temperature, take sample 2, the composition and temperature of the molten steel meet the requirements, and the LF molten steel is discharged.

[0013] The present application has the following beneficial effects:

[0014] The present application provides a LF refining method and a preparation method thereof. By accurately calculating the temperature of the molten steel when the temperature of the molten steel is heated to 1620 DEG C by the relationship between the total power consumption of the electric arc and the heating amount of the electric arc, the sulfur content in the molten steel is adjusted by adding ferrous sulfur, and according to W[S] 样1 % in sample 1 and (TFe%+MnO%), R, the amount of ferrous sulfur added is calculated, the timing and amount of ferrous sulfur added are accurately controlled, the manufacturing cost is reduced, the composition control precision of the molten steel is improved, and the smelting quality of the molten steel is improved. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme in the embodiments of the present application will be clearly and completely described below. If the specific conditions are not specified in the embodiments, the conventional conditions or the conditions recommended by the manufacturer are used. If the reagents or instruments used are not specified by the manufacturer, they are all conventional products that can be purchased in the market.

[0016] A LF refining method of 1.2312 die steel, comprising the following steps:

[0017] S1: the converter uses chromium-containing and molybdenum-containing scrap steel.

[0018] S2: the molten iron As≤0.050%, P≤0.130%, Sn≤0.020%, Cu≤0.030%.

[0019] S3: the converter tapping C is controlled at 0.10%-0.30%, P is controlled at ≤0.016%, and the tapping temperature is controlled at 1630±15℃.

[0020] S4: the converter tapping alloying and slag washing treatment are performed.

[0021] The alloying addition timing: at 2 / 5 of the tapping, 6.1-6.4kg / t steel of silicon manganese, 27-28kg / t steel of high-carbon chromium iron are added.

[0022] The slag washing material addition timing: at 3 / 5 of the tapping, 3.7-4.0kg / t steel of lime, preferably 3.8kg / t steel of lime, 0.75-0.9kg / t steel of bauxite, preferably 0.8kg / t steel of bauxite are added.

[0023] During alloying and slag washing, 60Nm 3 / h of argon is blown to ensure good melting effect.

[0024] S3: after the tapping is completed, the argon flow is adjusted to 5-10Nm 3 / h in soft blowing state to make the molten steel not exposed to air.

[0025] The argon station sampling, W[C] 氩站 %, W[Si] 氩站 %, W[Mn] 氩站 %, W[Cr] 氩站 %, W[Mo] 氩站 %, and other element chemical compositions.

[0026] S4: LF refining is performed:

[0027] S41: the inlet station temperature is measured to obtain Tinlet.

[0028] S42: 35Nm 3 / h of argon is blown, 11-grade power supply is used for slagging, and during the power supply process, 1-1.2kg / t steel of fluorite balls (preferably 1.1kg / t steel of fluorite balls), 2.3-2.4kg / t steel of low-alkali slag (preferably 2.35kg / t steel of low-alkali slag), and 3.05-3.2kg / t steel of lime (preferably 3.15kg / t steel of lime) are added in sequence. After 3min of 11-grade power supply slagging, 4-grade power supply is used.

[0029] 4th power supply process, the molten steel temperature to the steel liquidus temperature + 80 ℃ (i.e. 1565 ℃) or more, the argon 45Nm 3 / h, start adding the following materials (to raise the temperature of molten steel, to promote the rapid melting of material):

[0030] According to the W[C] of S3 step 氩站 %, when W[C] 氩站 % <0.29%, (0.29%-W[C] 氩站 %) carbon powder input for deoxidation, 3 times, one-third, to play a uniform diffusion deoxidation and rough adjustment of the role of [C]%. According to 0.13 kg carbon powder per ton of steel to increase W[C] 0.01%, the amount of carbon powder G 碳粉1 =0.13×(0.29%-W[C] 氩站 %) / 0.01% kg / ton steel, the amount of carbon powder G 碳粉0 =0.13×(0.29%-W[C] 氩站 %) ÷3 kg / ton steel.

[0031] When W[C] 氩站 % ≥0.29%, (0.20%-W[Si] 氩站 %) ferrosilicon powder input for deoxidation, 3 times, one-third, to play a uniform diffusion deoxidation and rough adjustment of the role of [Si]%. According to 0.136 kg ferrosilicon powder per ton of steel to increase W[Si] 0.01%, the amount of ferrosilicon powder G 硅铁粉1 =0.136×(0.20%-W[Si] 氩站 %) / 0.01% kg / ton steel, the amount of ferrosilicon powder G 硅铁粉0 =0.136×(0.20%-W[Si] 氩站 %) ÷3 kg / ton steel.

[0032] According to the W[Mn] of S3 step 氩站 %, (1.45%-W[Mn] 氩站 %) high carbon ferromanganese for alloying rough adjustment of the composition. According to 0.144 kg high carbon ferromanganese per ton of steel to increase W[Mn] 0.01%, the amount of high carbon ferromanganese G 高碳锰铁0 =0.144×(1.45%-W[Mn] 氩站 %) / 0.01% kg / ton steel.

[0033] According to the W[Cr] of S3 step 氩站 %, (1.85%-W[Cr] 氩站% ) to add high-carbon chromium iron for alloying rough composition. According to the increase of W [Cr] 0.001% by 0.176 kg high-carbon chromium iron per ton of steel, the input amount G of high-carbon chromium iron 高碳铬铁0 = 0.176 x (1.85% - W [Cr] 氩站 % ) / 0.001% kg / ton of steel.

[0034] According to the S3 step, W [Mo] 氩站 % is obtained, and (0.16% - W [Mo] 氩站 % ) is added to add molybdenum iron for alloying rough composition. According to the increase of W [Mo] 0.01% by 0.16 kg molybdenum iron per ton of steel, the input amount G of molybdenum iron 钼铁0 = 0.16 x (0.16% - W [Mo] 氩站 % ) / 0.01% kg / ton of steel.

[0035] S43: In the production process, it is found that when the molten steel is heated to 1620℃, the deoxidation alloying and desulfurization reactions are basically completed, and sulfur iron is then added most accurately. According to the relationship between the total arc power consumption Q (kwh) and the arc heating amount K (℃), the total arc power consumption when the molten steel is heated to 1620℃ is calculated, and the molten steel temperature is accurately controlled. Specifically, when the molten steel is heated to 1620℃, the total arc power consumption Q = arc heating amount K x 33 x 0.6 = [1620 - T 进站 + △T 渣料 + △T 合金 ) ÷ 0.8 x 2] x 33 x 0.6, wherein T 进站 is the LF inlet temperature (℃), △T 渣料 is the slag cooling (℃), △T 合金 is the alloy cooling (℃), the unit of total arc power consumption Q is kWh, the units of T 进站 , △T 渣料 , and △T 合金 are all ℃, further, both △T 渣料 and △T 合金 are 0.8 kg / ton of steel cooling 2℃, that is, through calculation, it is known that the total arc power consumption at a certain reading can accurately reach the arc heating amount and the required heating target temperature.

[0036] S44: When the molten steel is heated to 1620℃, argon gas 90 Nm 3 / h is introduced for strong stirring for 3 min, and then argon gas 20 Nm 3 / h is introduced for temperature measurement, sampling 1, and slag sticking operation.

[0037] Sampling 1 detection shows: W[C] 样1 %, W[Si] 样1 %, W[Mn] 样1 %, W[S] 样1%, W[Cr] 样1 %, W[Mo] 样1 %.

[0038] S45: argon 35 Nm 3 / h, continue to supply power to warm up.

[0039] According to the S44 step, the sample 1 test results are obtained: W[C] 样1 %, W[Si] 样1 %, W[Mn] 样1 %, W[S] 样1 %, W[Cr] 样1 %, W[Mo] 样1 %, respectively, according to the chemical composition of each element requirement target value adjustment in place.

[0040] According to TFe%, MnO%, R, calculate the amount of ferrous sulfide added, adjust the S content in the molten steel:

[0041] When (TFe% + MnO%) = 1% and R = 2, the S element content of the molten steel is stable (no S is not removed and S is not returned), at this time no additional increase or decrease of ferrous sulfide is required; according to 0.027 kg of ferrous sulfide per ton of steel, the increase of W[S] 0.001%, the amount of ferrous sulfide G 硫铁0 = 0.027 × (W[S] 目标 % - W[S] 样1 %) / 0.001% kg / ton steel, W[S] 目标 % is 0.07%;

[0042] When (TFe% + MnO%) <1%, 2 < R <2.2, the molten steel will continue to appear a certain amount of S, and W[S]% 样1 The subsequent S is related to the proportion of (TFe% + MnO%) =1 and R =2, and the following formula is obtained: W[S] 样1后脱S %:△W[S] 样1后脱S %= W[S] 样1 % × [1- (FeO% + MnO%) ×100] × (R-2). According to 0.027 kg of ferrous sulfide per ton of steel, the increase of W[S] 0.001%, the amount of ferrous sulfide G 硫铁1 = 0.027 × (W[S] 样目标 % - W[S] 样1 % -△W[S] 样1后脱S %) = 0.027 × {0.07% - W[S] 样1 % + W[S] 样1 % × [1- (FeO% + MnO%) ×100] × (R-2)} / 0.001% kg / ton steel.

[0043] When (TFe% + MnO%) > 1% and 1.8 < R < 2, a certain amount of S will continue to occur, and the subsequent S of W[S]%1 has a proportional relationship with the baseline (TFe% + MnO%) = 1 and R = 2, resulting in the following formula: W[S] 样1后回S %: △W[S] 样1后回S % = W[S] 样1 % × [(FeO% + MnO%) × 100 - 1] × (2 - R). Based on an increase of 0.001% in W[S] per ton of steel (0.027 kg ferrosulfite), the ferrosulfite input G... 硫铁2 =0.027×(W[S]) 目标 %-W[S] 样1 %-△W[S] 样1后回S %) = 0.027 × {0.07% - W[S]} 样1 %-W[S] 样1 %×[(FeO%+MnO%)×100-1]×(2-R)} / 0.001%kg / ton of steel.

[0044] According to W[Si] 样1 %, calculate the amount of ferrosilicon added, and adjust the Si content in the molten steel: Si is an easily oxidized element in molten steel, and 35 Nm of argon gas is introduced per unit volume. 3 A 5-minute supply of electricity per hour will result in an oxidation loss of 0.01%, ΔW[Si]. 损失 % = S 样1后升温 ÷5×0.01%, where S 样1后升温 The heating time (in minutes) after sampling 1 is completed. Therefore, based on an increase of 0.01% in W[Si] by 0.14 kg ferrosilicon powder / ton of steel, the amount of ferrosilicon input G is calculated. 硅铁1 =0.14×(W[Si]) 目标 %-W[Si] 样1 %-△W[Si] 损失 %) = 0.14 × (0.40% - W[Si]) 样1 %+S 样1后升温 ÷5×0.01%) / 0.01%kg / ton of steel; where W[Si] 目标 The percentage is 0.40%.

[0045] According to W[Mn] 样1 %, calculate the amount of high-carbon ferromanganese added, and adjust the Mn content in the molten steel: Calculate the amount of high-carbon ferromanganese added (G) based on an increase of W[Mn] of 0.01% per ton of steel (0.144 kg high-carbon ferromanganese / ton). 高碳锰铁1 =0.144×(W[Mn]) 目标 %-W[Mn] 样1 % ) = 0.144 × (1.50% - W[Mn]) 样1%) / 0.01% kg / ton of steel.

[0046] According to W[C] 样1 %, calculate the carbon powder addition amount to adjust the C content in the molten steel: since high-carbon ferromanganese contains carbon, increase W[C] 0.01% by 1.6 kg high-carbon ferromanganese / ton of steel, and the high-carbon ferromanganese carbon increment G 高碳锰铁增碳1 = G 高碳锰铁1 ÷ 1.6 x 0.01% = 0.144 x (1.50% - W[Mn] 样1 %) ÷ 1.6 kg / ton of steel; wherein W[Mn] 目标 % is 1.50%. Increase W[C] 0.01% by 0.13 kg carbon powder / ton of steel, and remove the high-carbon ferromanganese carbon increment G 高碳锰铁增碳1 , the carbon powder input amount G 碳粉1 = 0.13 x (W[C] 目标 % - W[C] 样1 % - G 高碳锰铁增碳1 ) = 0.13 x (W[C] 目标 % - W[C] 样1 % - 0.144 x (1.50% - W[Mn] 样1 %) ÷ 1.6) kg / ton of steel; wherein W[C] 目标 % is 0.38%.

[0047] According to W[Cr] 样1 %, calculate the chromium iron addition amount to adjust the Cr content in the molten steel: increase W[Cr] 0.001% by 0.176 kg chromium iron / ton of steel, and the high-carbon chromium iron input amount G 高碳铬铁1 = 0.176 x (W[Cr] 目标 % - W[Cr] 样1 %) = 0.176 x (1.90% - W[Cr] 样1 %) / 0.01% kg / ton of steel; wherein W[Cr] 目标 % is 1.90%.

[0048] According to W[[Mo] 样1 %, calculate the molybdenum iron addition amount to adjust the Mo content in the molten steel: increase W[Mo] 0.01% by 0.16 kg molybdenum iron / ton of steel, and the molybdenum iron input amount G 钼铁1 = 0.16 x (W[Mo] 目标 % - W[Mo] 样1 %) = 0.16 x (0.17% - W[Mo] 样1 %) / 0.01% kg / ton of steel.

[0049] S46: Continue to supply power to warm up to the required temperature for RH out.

[0050] S47: Introduce 20 Nm of argon gas. 3 / h, perform temperature measurement and sampling 2. Obtain W[C] 样2 %, W[Si] 样2 %, W[Mn] 样2 %, W[S] 样2 %, W[Cr] 样2 %, W[Mo] 样2 % of element content.

[0051] S48: Passed through RH vacuum treatment.

[0052] S49: RH inbound temperature measurement operation.

[0053] S50: Start vacuum degassing (argon circulation, circulation flow rate 45-72 Nm) 3 / h), vacuum degree ≤0.266kPa, high vacuum time ≥15min, pure degassing time ≥10min, vacuum treatment time ≥18min.

[0054] S51: Introduce argon gas at 5-10 Nm. 3 / h, add insulating rice husks, soft blow for 10-20 minutes, then measure temperature and take samples. Obtain W[C]. RH %, W[Si] RH %, W[Mn] RH %, W[S] RH %, W[Cr] RH %, W[Mo] RH % of element content.

[0055] S52: Molten steel exits the station and is continuously cast.

[0056] The present invention will be further described below with reference to embodiments.

[0057] Example 1

[0058] S1: The converter uses chromium- and molybdenum-containing scrap steel.

[0059] S2: Molten iron, As: 0.030%, P: 0.110%, Sn: 0.010%, Cu: 0.025%.

[0060] S3: Converter tapping C: 0.18%, P: 0.012%, tapping temperature: 1620℃.

[0061] S4: Perform alloying and slag washing treatment on the steel produced from the converter.

[0062] When to add alloying: Add 6.1 kg / ton of silicon manganese and 27 kg / ton of high-carbon ferrochrome when the steel is 2 / 5 of the way through the tapping process.

[0063] Slag washing material adding time: 3.8 kg lime / ton of steel and 0.8 kg bauxite / ton of steel were added at 3 / 5 of tapping.

[0064] During alloying and slag washing, argon was blown at a flow rate of 60 Nm 3 / h to ensure good melting effect.

[0065] S3: After tapping, the argon flow rate was reduced to 8 Nm 3 / h to keep the molten steel from being exposed to the atmosphere.

[0066] Sampling at the argon station showed that the W[C] 氩站 % was 0.24%, the W[Si] 氩站 % was 0.16%, the W[Mn] 氩站 % was 0.48%, the W[Cr] 氩站 % was 1.28%, and the W[Mo] 氩站 % was 0.01%.

[0067] S4: LF refining was carried out.

[0068] S41: The temperature at the inlet was measured, and the T_inlet was 1502℃.

[0069] S42: Argon was blown at a flow rate of 35 Nm 3 / h, and 11-grade power supply was used for slagging. Fluorite balls 1.1 kg / ton of steel, low-alkali slag 2.35 kg / ton of steel, and lime 3.15 kg / ton of steel were added successively during the power supply process. After 3 minutes of 11-grade power supply slagging, the power supply was switched to 4-grade.

[0070] During the 4-grade power supply process, the molten steel was heated to 1570℃, argon was blown at a flow rate of 45 Nm 3 / h, and the following materials were added (to increase the temperature of the molten steel to facilitate rapid melting of the materials):

[0071] According to the S3 step, the W[C] 氩站 % was 0.24%. When the W[C] 氩站 % was less than 0.29%, (0.29%-W[C] 氩站 %) = (0.29%-0.24%) = 0.05% of carbon powder was added for deoxidization, which was added in three equal portions to achieve uniform diffusion deoxidization and coarse adjustment of the [C] % of the molten steel. The amount of carbon powder added G 碳粉1 = 0.13×(0.29%-W[C] 氩站 %) = 0.13×(0.29%-0.24%) = 0.65 kg / ton of steel. The amount of carbon powder added each time G 碳粉0 = 0.13×(0.29%-W[C] 氩站= 0.136 x (0.20% - W[Si]%) = 0.136 x (0.20% - 0.16%) = 0.54 kg / ton steel, the silicon iron powder input amount G

[0072] When W[C] 氩站 ≥ 0.29%, according to (0.20% - W[Si]% 氩站 = (0.20% - 0.16%) = 0.04%, silicon iron powder is input for deoxidization, and is input in three times, each one third, to play the role of uniform diffusion deoxidization and rough adjustment of [Si]% in molten steel. According to 0.136 kg silicon iron powder / ton steel to increase W[Si] 0.01%, the silicon iron powder input amount G 硅铁粉1 = 0.136 x (0.20% - W[Si]% 氩站 = 0.136 x (0.20% - 0.16%) = 0.54 kg / ton steel, the silicon iron powder input amount G 硅铁粉0 = 0.136 x (0.20% - W[Si]% 氩站 = 0.136 x (0.20% - 0.16%) = 0.54 kg / ton steel, the silicon iron powder input amount G

[0073] According to the S3 step, W[Mn] 氩站 %: 0.48%, according to (1.45% - W[Mn]% 氩站 = (1.45% - 0.48%) = 0.97%, high-carbon manganese iron is added for alloying rough adjustment of composition. According to 0.144 kg high-carbon manganese iron / ton steel to increase W[Mn] 0.01%, the high-carbon manganese iron input amount G 高碳锰铁0 = 0.144 x (1.45% - W[Mn]% 氩站 = 0.144 x (1.45% - 0.48%) = 13.97 kg / ton steel.

[0074] According to the S3 step, W[Cr] 氩站 %: 1.28%, according to (1.85% - W[Cr]% 氩站 = (1.85% - 1.28%) = 0.57%, high-carbon chromium iron is added for alloying rough adjustment of composition. According to 0.176 kg high-carbon chromium iron / ton steel to increase W[Cr] 0.001%, the high-carbon chromium iron input amount G 高碳铬铁0 = 0.176 x (1.85% - W[Cr]% 氩 = 0.176 x (1.85% - 1.28%) = 10.03 kg / ton steel.

[0075] According to the S3 step, W[Mo] 氩站 %: 0.01%, according to (0.16% - W[Mo]% 氩站(%) = (0.16% - 0.01%) = 0.15% Molybdenum iron is added for alloying. The amount of molybdenum iron G is calculated according to the increase of W[Mo] 0.01% by 0.16 kg of molybdenum iron per ton of steel. 钼铁0 = 0.16 x (0.16% - W[Mo] 氩站 %) = 0.16 x (0.16% - 0.01%) = 2.4 kg / ton of steel.

[0076] S43: In the production process, it is found that when the molten steel is heated to 1620℃, the deoxidation and alloying and desulfurization reactions are basically completed, and thereafter the most accurate sulfur iron is added. The total arc power consumption Q is calculated when the molten steel is heated to 1620℃, Q = arc heating amount K x 33 x 0.6 = [1620 - T 进站 + (△T 渣料 + △T 合金 ) ÷ 0.8 x 2] x 33 x 0.6 = [1620 - 1502 + (6.6 + 27.59) ÷ 0.8 x 2] x 33 x 0.6 = 16924. When the total arc power consumption of the ammeter reading is 16924, the temperature of the molten steel is just 1620℃.

[0077] S44: The molten steel is heated to 1620℃, argon gas is introduced at a rate of 90 Nm 3 / h for 3 minutes, then argon gas is introduced at a rate of 20 Nm 3 / h, temperature measurement, sampling 1, and slag sticking operations are performed.

[0078] Sampling 1 detection results: W[C] 样1 %: 0.37%, W[Si] 样1 %: 0.39%, W[Mn] 样1 %: 1.48%, W[S] 样1 %: 0.015%, W[Cr] 样1 %: 1.87%, W[Mo] 样1 %: 0.16%.

[0079] Slag sticking detection results: TFe%: 0.53%, MnO%: 0.34%, R: 2.1.

[0080] S45: Argon gas is introduced at a rate of 35 Nm 3 / h, and the power supply is continued to heat up.

[0081] According to the sampling 1 detection results obtained in the S44 step: W[C] 样1 %: 0.37%, W[Si] 样1 %: 0.39%, W[Mn] 样1 %: 1.48%, W[S] 样1 %: 0.015%, W[Cr] 样1 %: 1.87%, W[Mo]样1 %: 0.16%, respectively, according to the target value of each element chemical composition requirements in place.

[0082] According to TFe%: 0.53%, MnO%: 0.34%, R: 2.1, calculate the amount of ferrous sulfide, adjust the S content in the molten steel:

[0083] When (TFe% + MnO%) = 1 and R = 2, the S content of the molten steel is stable (not S or S); At this time, there is no need to increase or decrease the amount of ferrous sulfide; According to 0.027 kg of ferrous sulfide per ton of steel, the amount of ferrous sulfide G is calculated by increasing W[S]0.001%: 硫铁0 = 0.027 × (W[S] 目标 % - W[S] 样1 %) = 0.027 × (0.07% - 0.015%) = 0.149 kg / ton steel.

[0084] When (TFe% + MnO%) <1%, 2 < R < 2.2, the molten steel will continue to appear a certain amount of S, and W[S]% 样1 The subsequent S and (TFe% + MnO%) = 1 and R = 2 benchmark exist proportional relationship, the following formula is obtained:

[0085] W[S] 样1后脱S %: △W[S] 样1后脱S % = W[S] 样1 % × [1 - (FeO% + MnO%) × 100] × (R - 2) = 0.015% × [1 - (0.53% + 0.34%) × 100] × (2.1 - 2) = 0.002%. According to 0.027 kg of ferrous sulfide per ton of steel, the amount of ferrous sulfide G is calculated by increasing W[S]0.001%: 硫铁1 = 0.027 × (W[S] 样目标 % - W[S] 样1 % - △W[S] 样1后脱S %) = 0.027 × {0.07% - W[S] 样1 % + W[S] 样1 % × [1 - (FeO% + MnO%) × 100] × (R - 2)} = 0.027 × {0.07% - 0.015% + 0.015% × [1 - (0.53% + 0.34%) × 100] × (2.1 - 2)} = 1.54 kg / ton steel.

[0086] When (TFe% + MnO%) >1%, 1.8 < R < 2, a certain amount of S will continue to appear, and W[S]% 1The subsequent S and (TFe% + MnO%) = 1 and R = 2 benchmark exist proportional relationship, the following formula is obtained:

[0087] W[S] 样1后回S%: ΔW[S] 样1后回S % = W[S] 样1 % × [(FeO% + MnO%) × 100 - 1] × (2 - R). W[S] is increased by 0.001% with G of 0.027 kg of ferrous sulphur per ton of steel 硫铁2 = 0.027 × (W[S] 目标 % - W[S] 样1 % - ΔW[S] 样1后回S % ) = 0.027 × {0.07% - W[S] 样1 % - W[S] 样1 % × [(FeO% + MnO%) × 100 - 1] × (2 - R) kg per ton of steel.

[0088] According to W[Si] 样1 % : 0.39%, calculate the ferrosilicon addition to adjust the Si content in the molten steel: W[Si] of the molten steel is an easily oxidized element, and 0.01% of oxidation loss is caused by 35 Nm 3 of argon gas per hour for 5 min, and ΔW[Si] 损失 % = S 样1后升温 ÷ 5 × 0.01% = 10 ÷ 5 × 0.01% = 0.02%, wherein S 样1后升温 is the heating time (min) after the sample 1 is taken. Therefore, W[Si] is increased by 0.01% with G of 0.14 kg of ferrosilicon powder per ton of steel for 10 min 硅铁1 = 0.14 × (W[Si] 目标 % - W[Si] 样1 % + ΔW[Si] 损失 % ) = 0.14 × (0.40% - W[Si] 样1 % + S 样1后升温 ÷ 5 × 0.01% = 0.14 × (0.40% - 0.39% + 0.02%) = 0.42 kg per ton of steel; wherein W[Si] 目标 % is 0.40%.

[0089] According to W[Mn] 样1 % : 1.48%, calculate the high-carbon ferromanganese addition to adjust the Mn content in the molten steel: W[Mn] is increased by 0.01% with G of 0.144 kg of high-carbon ferromanganese per ton of steel 高碳锰铁1 = 0.144 × (W[Mn] 目标 % - W[Mn] 样1 % ) = 0.144 × (1.50% - W[Mn] 样1 % ) = 0.144 × (1.50% - 1.48%) = 0.29 kg per ton of steel.

[0090] According to W[C] 样1 %: 0.37%, calculate the carbon powder addition amount, adjust the C content in the molten steel: since high-carbon ferromanganese contains carbon, increase W[C] 0.01% by 1.6 kg high-carbon ferromanganese per ton of steel, the high-carbon ferromanganese carbon increase G 高碳锰铁增碳1 = G 高碳锰铁1 ÷ 1.6 x 0.01% = 0.144 x (1.50% - W[Mn] 样1 % ÷ 1.6 x 0.01% = 0.144 x (1.50% - 1.48%) ÷ 1.6 x 0.01% = 0.002%; wherein W[Mn] ) % is 1.50%. Increase W[C] 0.01% by 0.13 kg carbon powder per ton of steel, remove the high-carbon ferromanganese carbon increase G 目标 , the carbon powder input amount G 高碳锰铁增碳1 = 0.13 x (W[C] 碳粉1 % - W[C] 目标 % - G 样1 ) = 0.13 x (W[C] 高碳锰铁增碳1 % - W[C] 目标 % - 0.144 x (1.50% - W[Mn] 样1 %) ÷ 1.6 x 0.01%) = 0.13 x (0.38% - 0.37% - 0.144 x (1.50% - 1.48%) ÷ 1.6 x 0.01%) = 0.10 kg per ton of steel; wherein W[C] 样1 % is 0.38%.

[0091] According to W[Cr] 目标 %: 1.87%, calculate the chromium iron addition amount, adjust the Cr content in the molten steel: increase W[Cr] 0.001% by 0.176 kg chromium iron per ton of steel, the high-carbon chromium iron input amount G 样1 = 0.176 x (W[Cr] 高碳铬铁1 % - W[Cr] 目标 %) = 0.176 x (1.90% - W[Cr] 样1 %) = 0.176 x (1.90% - 1.87%) = 0.53 kg per ton of steel; wherein W[Cr] 样1 % is 1.90%.

[0092] According to W[[Mo] 目标 %: 0.16%, calculate the molybdenum iron addition amount, adjust the Mo content in the molten steel: increase W[Mo] 0.01% by 0.16 kg molybdenum iron per ton of steel, the molybdenum iron input amount G 样1 = 0.16 x (W[Mo] 钼铁1 % - W[Mo] 目标 %) = 0.16 x (0.20% - W[Mo] 样1% = 0.16 x (0.17% - W[Mo] 样1 % = 0.16 x (0.17% - 0.16%) = 0.16 kg / ton steel.

[0093] S46: Continue to supply power to warm up to the required temperature of 1585°C for RH out.

[0094] S47: Argon is introduced at 20 Nm 3 / h, temperature measurement and sampling are performed. The W[C] 样2 % is 0.38%, W[Si] 样2 % is 0.40%, W[Mn] 样2 % is 1.50%, W[S] 样2 % is 0.07%, W[Cr] 样2 % is 1.90%, W[Mo] 样2 % is 0.17%, and the content of other elements.

[0095] S48: RH vacuum treatment is performed.

[0096] S49: RH in-station temperature measurement operation is performed, and the temperature is 1565°C.

[0097] S50: Vacuum degassing is started (argon circulation, circulation flow rate is 50 Nm 3 / h), vacuum degree is 0.262 kPa, high vacuum time is 18 min, pure degassing time is 12 min, and vacuum treatment time is 21 min.

[0098] S51: Argon is introduced at 5 Nm 3 / h, insulation husks are added, soft blowing is performed for 15 min, and temperature measurement and sampling operations are performed. The temperature is 1532°C. The W[C] RH % is 0.37%, W[Si] RH % is 0.39%, W[Mn] RH % is 1.50%, W[S] RH % is 0.069%, W[Cr] RH % is 1.89%, W[Mo] RH % is 0.17%, and the content of other elements.

[0099] S52: The molten steel is discharged and connected to continuous casting for casting.

[0100] Example 2

[0101] S1: A converter uses chromium-containing and molybdenum-containing scrap steel.

[0102] S2: The molten iron As: 0.044%, P: 0.120%, Sn: 0.010%, Cu: 0.015%.

[0103] S3: Converter tapping C: 0.20%, P: 0.010%, tapping temperature: 1631 °C.

[0104] S4: Converter tapping alloying and slag washing treatment.

[0105] Alloying addition timing: Silicon manganese 6.3 kg / ton steel, 26.8 kg high carbon chromium iron / ton steel was added at 2 / 5 tapping.

[0106] Slag washing material addition timing: 3.9 kg lime / ton steel, 0.85 kg bauxite / ton steel was added at 3 / 5 tapping.

[0107] During alloying and slag washing, argon was passed at 60 Nm 3 / h to ensure good melting effect.

[0108] After tapping, the argon flow was reduced to soft blowing at 6 Nm 3 / h to prevent the molten steel from being exposed to the atmosphere.

[0109] Argon station sampling gave W[C] 氩站 %: 0.26%, W[Si] 氩站 %: 0.15%, W[Mn] 氩站 %: 0.51%, W[Cr] 氩站 %: 1.30%, W[Mo] 氩站 %: 0.02%, and other element chemical composition.

[0110] S4: LF refining:

[0111] S41: Station temperature measurement gave Tstation: 1513 °C.

[0112] S42: Argon was passed at 35 Nm 3 / h, 11th gear power supply slag, during power supply fluorite balls 1.2 kg / ton steel, low alkali slag 2.32 kg / ton steel, lime 3.08 kg / ton steel were added in sequence. After 3 minutes of 11th gear power supply slag, change to 4th gear power supply.

[0113] During 4th gear power supply, the molten steel was heated to 1580 °C, argon was passed at 45 Nm 3 / h, and the following materials were added (to raise the molten steel temperature to facilitate rapid melting of the materials):

[0114] According to S3, W[C] 氩站 %: 0.26%, when W[C] 氩站 % < 0.29%, (0.29% - W[C] 氩站= 0.13 x (0.29% - W[C]%) = 0.13 x (0.29% - 0.26%) = 0.39 kg / ton steel, carbon powder input amount G 碳粉1 = 0.13 x (0.29% - W[C]%) = 0.13 x (0.29% - 0.26%) = 0.39 kg / ton steel, carbon powder input amount G 氩站 = 0.13 x (0.29% - W[C]%) = 0.13 x (0.29% - 0.26%) = 0.39 kg / ton steel, carbon powder input amount G 碳粉0 = 0.13 x (0.29% - W[C]%) = 0.13 x (0.29% - 0.26%) = 0.39 kg / ton steel, carbon powder input amount G 氩站 = 0.13 x (0.29% - W[C]%) = 0.13 x (0.29% - 0.26%) = 0.39 kg / ton steel, carbon powder input amount G

[0115] When W[C] 氩站 % ≥ 0.29%, (0.20% - W[Si]% 氩站 ) = (0.20% - 0.15%) = 0.05% silicon iron powder is input for deoxidation, which is input in three times, one third each time, to play a role in uniform diffusion deoxidation and rough adjustment of steel liquid [Si]%. According to the calculation of 0.136 kg silicon iron powder / ton steel to increase W[Si]0.01%, the silicon iron powder input amount G 硅铁粉1 = 0.136 x (0.20% - W[Si]%) = 0.136 x (0.20% - 0.15%) = 0.68 kg / ton steel, silicon iron powder input amount G 氩站 = 0.136 x (0.20% - W[Si]%) = 0.136 x (0.20% - 0.15%) = 0.68 kg / ton steel, silicon iron powder input amount G 硅铁粉0 = 0.136 x (0.20% - W[Si]%) = 0.136 x (0.20% - 0.15%) = 0.68 kg / ton steel, silicon iron powder input amount G 氩站 = 0.136 x (0.20% - W[Si]%) = 0.136 x (0.20% - 0.15%) = 0.68 kg / ton steel, silicon iron powder input amount G

[0116] According to the S3 step, W[Mn] 氩站 %: 0.51%, (1.45% - W[Mn]% 氩站 % = (1.45% - 0.51%) = 0.94% high-carbon ferromanganese is added for alloying rough adjustment of composition. According to the calculation of 0.144 kg high-carbon ferromanganese / ton steel to increase W[Mn]0.01%, the high-carbon ferromanganese input amount G 高碳锰铁0 = 0.144 x (1.45% - W[Mn]%) = 0.144 x (1.45% - 0.51%) = 13.54 kg / ton steel. 氩站 = 0.144 x (1.45% - W[Mn]%) = 0.144 x (1.45% - 0.51%) = 13.54 kg / ton steel.

[0117] According to the S3 step, W[Cr] 氩站 %: 1.30%, (1.85% - W[Cr]% 氩站= 0.176 x (1.85% - W[Cr] = 0.176 x (1.85% - 1.30%) = 9.68 kg / ton steel. 高碳铬铁0 = 0.176 x (1.85% - W[Cr] = 0.176 x (1.85% - 1.30%) = 9.68 kg / ton steel. 氩 = 0.176 x (1.85% - W[Cr] = 0.176 x (1.85% - 1.30%) = 9.68 kg / ton steel.

[0118] According to S3 step, W[Mo] 氩站 %: 0.02%, according to (0.16% - W[Mo] 氩站 %): (0.16% - 0.02%) = 0.14% Add molybdenum iron for alloying rough composition. According to 0.16 kg molybdenum iron per ton of steel, increase W[Mo] 0.01%, molybdenum iron input G 钼铁0 = 0.16 x (0.16% - W[Mo] 氩站 %): 0.16 x (0.16% - 0.02%) = 2.24 kg / ton steel.

[0119] S43: In the production process, it is found that when the molten steel is heated to 1625℃, the deoxidation alloying and desulfurization reaction is basically completed, and the total arc power consumption Q is calculated when the molten steel is heated to 1625℃, arc heating amount K x 33 x 0.6 = [1625-1513 + (6.6+26.53) ÷ 0.8 x 2] x 33 x 0.6 = 37575. When the total arc power consumption of the electric meter reading is 37575, the temperature of the molten steel is just 1625℃.

[0120] S44: When the molten steel is heated to 1625℃, argon gas is blown in at 90 Nm 3 / h strong stirring for 3 min, then argon gas is blown in at 20 Nm 3 / h, temperature measurement, sampling 1, and slag sticking operation are carried out.

[0121] Sampling 1 detection: W[C] 样1 %: 0.36%, W[Si] 样1 %: 0.38%, W[Mn] 样1 %: 1.49%, W[S] 样1 %: 0.011%, W[Cr] 样1 %: 1.88%, W[Mo] 样1 %: 0.16%.

[0122] Slag sticking detection: TFe%: 0.52%, MnO%: 0.48%, R: 2.

[0123] S45: Argon gas is blown in at 35 Nm 3 / h, and the power supply is continued to heat up.

[0124] According to the S44 step, the sample 1 test results are: W[C] 样1 %: 0.36%, W[Si] 样1 %: 0.38%, W[Mn] 样1 %: 1.49%, W[S] 样1 %: 0.011%, W[Cr] 样1 %: 1.88%, W[Mo] 样1 %: 0.16%, respectively, and the target values of the respective element chemical compositions are adjusted in place.

[0125] According to TFe%: 0.52%, MnO%: 0.48%, R: 2, the amount of ferrous sulfide is calculated, and the S content in the molten steel is adjusted:

[0126] When (TFe% + MnO%) = 1 and R = 2, the S content of the molten steel is stable (no S loss or S return); according to the calculation of 0.027 kg of ferrous sulfide per ton of steel to increase W[S] 0.001%, the amount of ferrous sulfide G 硫铁0 = 0.027 × (W[S] 目标 % - W[S] 样1 %) = 0.027 × (0.07% - 0.015%) = 0.149 kg / ton of steel.

[0127] When (TFe% + MnO%) < 1%, 2 < R < 2.2, the molten steel will continue to have a certain amount of S loss, and W[S]% 样1 The subsequent S loss has a proportional relationship with the reference of (TFe% + MnO%) = 1 and R = 2, and the following formula is obtained:

[0128] W[S] 样1后脱S %: △W[S] 样1后脱S % = W[S] 样1 % × [1 - (FeO% + MnO%) × 100] × (R - 2). According to the calculation of 0.027 kg of ferrous sulfide per ton of steel to increase W[S] 0.001%, the amount of ferrous sulfide G 硫铁1 = 0.027 × (W[S] 样目标 % - W[S] 样1 % - △W[S] 样1后脱S %) = 0.027 × {0.07% - W[S] 样1 % + W[S] 样1 % × [1 - (FeO% + MnO%) × 100] × (R - 2)} kg / ton of steel.

[0129] When (TFe% + MnO%) > 1% and 1.8 < R < 2, a certain amount of return to S will continue to occur, and the subsequent return to S of W[S]%1 is proportional to the baseline (TFe% + MnO%) = 1 and R = 2, resulting in the following formula:

[0130] W[S] 样1后回S %: △W[S] 样1后回S % = W[S] 样1 % × [(FeO% + MnO%) × 100 - 1] × (2 - R). Based on an increase of 0.001% in W[S] per ton of steel (0.027 kg ferrosulfite), the ferrosulfite input G... 硫铁2 =0.027×(W[S]) 目标 %-W[S] 样1 %-△W[S] 样1后回S %) = 0.027 × {0.07% - W[S]} 样1 %-W[S] 样1 %×[(FeO%+MnO%)×100-1]×(2-R)}kg / ton of steel.

[0131] According to W[Si] 样1 %: 0.38%, calculate the amount of ferrosilicon added, and adjust the Si content in the molten steel: Si is an easily oxidized element in molten steel, and 35 Nm of argon gas is introduced per unit volume. 3 A 5-minute power supply will result in a 0.01% oxidation loss; an 8-minute power supply will result in a ΔW[Si] loss. 损失 % = S 样1后升温 ÷5×0.01%=8÷5×0.01%=0.16%, where S 样1后升温 The heating time (in minutes) after sampling 1 is completed. Therefore, based on an increase of 0.01% in W[Si] by 0.14 kg ferrosilicon powder / ton of steel, and an 8-minute power supply, the amount of ferrosilicon added, G... 硅铁1 =0.14×(W[Si]) 目标 %-W[Si] 样1 %+△W[Si] 损失 %) = 0.14 × (0.40% - W[Si]) 样1 %+S 样1后升温 ÷5 × 0.01% = 0.14 × (0.40% - 0.38% + 0.016%) = 0.3 kg / ton of steel; where W[Si] 目标 The percentage is 0.40%.

[0132] According to W[Mn] 样1 %: 1.49%, calculate the amount of high-carbon ferromanganese added, and adjust the Mn content in the molten steel: based on 0.144 kg of high-carbon ferromanganese / ton of steel, increase W[Mn] by 0.01%, the amount of high-carbon ferromanganese added is G 高碳锰铁1 =0.144×(W[Mn])目标 % - W[Mn] % 样1 % ) = 0.144 x (1.50% - W[Mn] % 样1 ) = 0.144 x (1.50% - 1.49%) = 0.144 kg / ton steel.

[0133] According to W[C] 样1 % : 0.36%, calculate the carbon powder addition, adjust the C content in the molten steel: since high carbon ferromanganese contains carbon, increase W[C] 0.01% by 1.6 kg high carbon ferromanganese / ton steel, the high carbon ferromanganese carbon increment G 高碳锰铁增碳1 = G 高碳锰铁1 ÷ 1.6 x 0.01% = 0.144 x (1.50% - W[Mn] % 样1 ) ÷ 1.6 x 0.01% = 0.144 x (1.50% - 1.49%) ÷ 1.6 x 0.01% = 0.001%; wherein W[Mn] % 目标 % is 1.50%. Increase W[C] 0.01% by 0.13 kg carbon powder / ton steel, remove the high carbon ferromanganese carbon increment G 高碳锰铁增碳1 , the carbon powder input G 碳粉1 = 0.13 x (W[C] % 目标 % - W[C] % 样1 % - G 高碳锰铁增碳1 ) = 0.13 x (W[C] % 目标 % - W[C] % 样1 % - 0.144 x (1.50% - W[Mn] % 样1 % ÷ 1.6 x 0.01%) = 0.13 x (0.38% - 0.36% - 0.144 x (1.50% - 1.49%) ÷ 1.6 x 0.01%) = 0.25 kg / ton steel; wherein W[C] % 目标 % is 0.38%.

[0134] According to W[Cr] 样1 % : 1.88%, calculate the chromium iron addition, adjust the Cr content in the molten steel: increase W[Cr] 0.001% by 0.176 kg chromium iron / ton steel, the high carbon chromium iron input G 高碳铬铁1 = 0.176 x (W[Cr] % 目标 % - W[Cr] % 样1 %) = 0.176 x (1.90% - W[Cr] % 样1 %) = 0.176 x (1.90% - 1.88%) = 0.35 kg / ton steel; wherein W[Cr] % 目标 % is 1.90%.

[0135] According to W[[Mo] 样1%: 0.16%, calculate the amount of ferromolybdenum added, and adjust the Mo content in the molten steel: Calculate based on an increase of W[Mo] of 0.01% for every 0.16 kg of ferromolybdenum / ton of steel, the amount of ferromolybdenum added is G. 钼铁1 =0.16×(W[Mo]) 目标 %-W[Mo] 样1 %) = 0.16 × (0.17% - W[Mo]) 样1 %)=0.16×(0.17%-0.16%)=0.16kg / ton of steel.

[0136] S46: Continue power supply to heat up until the temperature reaches the required RH temperature of 1584℃ at the station exit.

[0137] S47: Introduce 20 Nm of argon gas. 3 / h, perform temperature measurement and sampling 2. Obtain W[C] 样2 %: 0.39%, W[Si] 样2 %: 0.39%, W[Mn] 样2 %: 1.50%, W[S] 样2 %: 0.071%, W[Cr] 样2 %: 1.91%, W[Mo] 样2 %: 0.17% of element content.

[0138] S48: Passed through RH vacuum treatment.

[0139] S49: The temperature measured at the RH inlet is 1564℃.

[0140] S50: Start vacuum degassing (argon circulation, circulation flow rate 48 Nm) 3 / h), vacuum degree 0.260kPa, high vacuum time 18min, pure degassing time 12min, vacuum treatment time 22min.

[0141] S51: Introduce 10 Nm of argon gas. 3 / h, add insulating rice husks, soft blowing for 12 minutes, temperature measurement and sampling. The temperature was found to be 1532℃. W[C] was obtained. RH %: 0.38%, W[Si] RH %: 0.40%, W[Mn] RH %: 1.49%, W[S] RH %: 0.071%, W[Cr] RH %: 1.90%, W[Mo] RH %: 0.17% of element content.

[0142] S52: Molten steel exits the station and is continuously cast.

[0143] Example 3

[0144] S1 : Converter using chromium containing scrap and molybdenum containing scrap.

[0145] S2: Hot metal As: 0.031%, P: 0.090%, Sn: 0.013%, Cu: 0.022%.

[0146] S3: Converter tapping C: 0.16%, P: 0.008%, tapping temperature: 1619°C.

[0147] S4: Converter tapping alloying and slag washing treatment.

[0148] Alloying addition timing: Silicon manganese 6.2 kg / ton steel, 27.6 kg high carbon chromium iron / ton steel at tapping 2 / 5.

[0149] Slag washing material addition timing: 3.9 kg lime / ton steel, 0.78 kg bauxite / ton steel at tapping 3 / 5.

[0150] During alloying and slag washing, argon gas is passed at 60 Nm 3 / h, ensuring good melting effect.

[0151] S3: After tapping, the argon gas flow is reduced to soft blowing state 9 Nm 3 / h, so that the liquid steel is not exposed to air.

[0152] Argon station sampling gives W[C] 氩站 %: 0.20%, W[Si] 氩站 %: 0.13%, W[Mn] 氩站 %: 0.49%, W[Cr] 氩站 %: 1.33%, W[Mo] 氩站 %: 0.01% and other element chemical composition.

[0153] S4: LF refining:

[0154] S41 : Station temperature measurement gives Tstation: 1501 °C.

[0155] S42: Argon gas is passed at 35 Nm 3 / h, 11th gear power supply slag, during power supply fluorite balls 1.16 kg / ton steel, low alkali slag 2.36 kg / ton steel, lime 3.14 kg / ton steel are added in succession. After 3 minutes of 11th gear power supply slag, change to 4th gear power supply.

[0156] During 4th gear power supply, the liquid steel is heated to 1567°C, argon gas is passed at 45 Nm 3 / h, the following materials are started to be added (to raise the liquid steel temperature to facilitate rapid melting of the materials):

[0157] W[C] is obtained according to S3 step氩站 %: 0.20%, when W[C] 氩站 % < 0.29%, (0.29%-W[C] 氩站 %) = (0.29%-0.20%) = 0.09% carbon powder is added for deoxidization, and is added in three times, one third each time, to play the role of uniform diffusion deoxidization and rough adjustment of the [C] % of the molten steel. According to the calculation of 0.13 kg carbon powder per ton of steel to increase W[C] 0.01%, the carbon powder input G 碳粉1 = 0.13 x (0.29%-W[C] 氩站 %) = 0.13 x (0.29%-0.20%) = 1.17 kg / ton of steel. The carbon powder input G 碳粉0 = 0.13 x (0.29%-W[C] 氩站 %) ÷ 3 = 0.13 x (0.29%-0.20%) ÷ 3 = 0.39 kg / ton of steel.

[0158] When W[C] 氩站 % ≥ 0.29%, (0.20%-W[Si] 氩站 %) = (0.20%-0.13%) = 0.07% ferrosilicon powder is added for deoxidization, and is added in three times, one third each time, to play the role of uniform diffusion deoxidization and rough adjustment of the [Si] % of the molten steel. According to the calculation of 0.136 kg ferrosilicon powder per ton of steel to increase W[Si] 0.01%, the ferrosilicon powder input G 硅铁粉1 = 0.136 x (0.20%-W[Si] 氩站 %) = 0.136 x (0.20%-0.13%) = 0.952 kg / ton of steel. The ferrosilicon powder input G 硅铁粉0 = 0.136 x (0.20%-W[Si] 氩站 %) ÷ 3 = 0.136 x (0.20%-0.13%) ÷ 3 = 0.32 kg / ton of steel.

[0159] According to the S3 step, W[Mn] 氩站 %: 0.49%, (1.45%-W[Mn] 氩站 %) = (1.45%-0.49%) = 0.96% high-carbon ferromanganese is added for alloying rough adjustment of the composition. According to the calculation of 0.144 kg high-carbon ferromanganese per ton of steel to increase W[Mn] 0.01%, the high-carbon ferromanganese input G 高碳锰铁0 = 0.144 x (1.45%-W[Mn] 氩站 %) = 0.144 x (1.45%-0.49%) = 13.82 kg / ton of steel.

[0160] According to the S3 step, W[Cr] 氩站 %: 1.33%, (1.85%-W[Cr]氩站 (1.85% - 1.33%) = 0.52% Add high-carbon chromium iron for alloying rough adjustment of composition. According to 0.176 kg high-carbon chromium iron per ton of steel, increase W[Cr] 0.001%, the input amount G of high-carbon chromium iron 高碳铬铁0 = 0.176 x (1.85% - W[Cr] 氩 %) = 0.176 x (1.85% - 1.33%) = 9.15 kg / ton of steel.

[0161] According to S3 step, W[Mo] 氩站 %: 0.01%, according to (0.16% - W[Mo] 氩站 %) = (0.16% - 0.01%) = 0.15% Add molybdenum iron for alloying rough adjustment of composition. According to 0.16 kg molybdenum iron per ton of steel, increase W[Mo] 0.01%, the input amount G of molybdenum iron 钼铁0 = 0.16 x (0.16% - W[Mo] 氩站 %) = 0.16 x (0.16% - 0.01%) = 2.4 kg / ton of steel.

[0162] S43: In the production process, it is found that when the molten steel is heated to 1620℃, the deoxidation alloying and desulfurization reactions are basically completed, and the most accurate sulfur iron is added thereafter. Calculate the total arc power consumption Q when the molten steel is heated to 1622℃: Q = arc heating amount K x 33 x 0.6 = [1622 - 1501 + (6.66 + 27.49) ÷ 0.8 x 2] x 33 x 0.6 = 40862. When the total arc power consumption of the electric meter reading is 40862, the temperature of the molten steel is just 1622℃.

[0163] S44: When the molten steel is heated to 1622℃, 90 Nm 3 / h of argon is introduced for 3 minutes, and then 20 Nm 3 / h of argon is introduced, temperature measurement, sampling 1, and slag sticking operations are performed.

[0164] Sampling 1 detection: W[C] 样1 %: 0.35%, W[Si] 样1 %: 0.39%, W[Mn] 样1 %: 1.48%, W[S] 样1 %: 0.009%, W[Cr] 样1 %: 1.87%, W[Mo] 样1 %: 0.15%.

[0165] Slag sticking detection: TFe%: 0.61%, MnO%: 0.55%, R: 1.9.

[0166] S45: 35 Nm 3 / h, continue to supply power to warm up.

[0167] According to the S44 step, the sample 1 test results are: W[C] 样1 %: 0.35%, W[Si] 样1 %: 0.39%, W[Mn] 样1 %: 1.48%, W[S] 样1 %: 0.009%, W[Cr] 样1 %: 1.87%, W[Mo] 样1 %: 0.15%, respectively, according to the target value of the chemical composition of each element to adjust in place.

[0168] According to TFe%: 0.61%, MnO%: 0.55%, R: 1.9, calculate the amount of ferrous sulfide added to adjust the S content in the molten steel:

[0169] When (TFe% + MnO%) = 1 and R = 2, the S content of the molten steel is stable (no S loss or S return); according to the increase of 0.027 kg of ferrous sulfide per ton of steel, the W[S] 0.001% is calculated, the amount of ferrous sulfide G 硫铁0 = 0.027 × (W[S] 目标 % - W[S] 样1 %) = 0.1647 kg / ton of steel.

[0170] When (TFe% + MnO%) < 1%, 2 < R < 2.2, the molten steel will continue to have a certain amount of S loss, and W[S]% 样1 The subsequent S loss and (TFe% + MnO%) = 1 and R = 2 benchmark exist proportional relationship, the following formula is obtained:

[0171] W[S] 样1后脱S %: △W[S] 样1后脱S % = W[S] 样1 % × [1 - (FeO% + MnO%) × 100] × (R - 2). According to the increase of 0.027 kg of ferrous sulfide per ton of steel, the W[S] 0.001% is calculated, the amount of ferrous sulfide G 硫铁1 = 0.027 × (W[S] 样目标 % - W[S] 样1 % - △W[S] 样1后脱S %) = 0.027 × {0.07% - W[S] 样1 % + W[S] 样1 % × [1 - (FeO% + MnO%) × 100] × (R - 2)} kg / ton of steel.

[0172] When (TFe% + MnO%) > 1%, 1.8 < R < 2, a certain amount of S will continue to appear, and the subsequent S and the reference of (TFe% + MnO%) = 1 and R = 2 exist in a proportional relationship, and the following formula is obtained:

[0173] W[S] 样1后回S %: △W[S] 样1后回S % = W[S] 样1 % × [(FeO% + MnO%) × 100 - 1] × (2 - R). According to the increase of 0.027 kg of ferrous sulfide per ton of steel, W[S] is increased by 0.001%, and the input amount G of ferrous sulfide 硫铁2 = 0.027 × (W[S] 目标 % - W[S] 样1 % - △W[S] 样1后回S %) = 0.027 × {0.07% - W[S] 样1 % - W[S] 样1 % × [(FeO% + MnO%) × 100 - 1] × (2 - R)} = 0.027 × {0.07% - 0.009% - 0.009% × [(0.61% + 0.55%) × 100 - 1] × (2 - 1.9)} = 1.27 kg / ton of steel.

[0174] According to W[Si] 样1 %, 0.39%, the amount of ferrosilicon is calculated to adjust the Si content in the molten steel: W[Si] in molten steel is an easily oxidized element, and 0.01% of oxidation loss will be caused by supplying 5 minutes of argon gas 35 Nm 3 / h. If the power supply is 9 minutes, △W[Si] 损失 % = S 样1后升温 ÷ 5 × 0.01% = 9 ÷ 5 × 0.01% = 0.018%, wherein S 样1后升温 is the heating time (min) after the sample is taken. Therefore, according to the increase of 0.14 kg of ferrosilicon powder per ton of steel, W[Si] is increased by 0.01%, the power supply is 9 minutes, and the input amount G of ferrosilicon 硅铁1 = 0.14 × (W[Si] 目标 % - W[Si] 样1 % + △W[Si] 损失 %) = 0.14 × (0.40% - W[Si] 样1 % + S 样1后升温 ÷ 5 × 0.01% = 0.14 × (0.40% - 0.39% + 0.018%) = 0.17 kg / ton of steel; wherein W[Si] 目标 % is 0.40%.

[0175] According to W[Mn] 样1%: 1.48%, calculate high carbon ferromanganese addition amount, adjust the Mn content in the molten steel: according to 0.144 kg high carbon ferromanganese per ton of steel to increase W[Mn] 0.01%, high carbon ferromanganese input amount G 高碳锰铁1 = 0.144 x (W[Mn] 目标 % - W[Mn] 样1 %) ) = 0.144 x (1.50% - W[Mn] 样1 %) = 0.144 x (1.50% - 1.48%) = 0.29 kg / ton of steel.

[0176] According to W[C] 样1 %: 0.35%, calculate the carbon powder addition amount, adjust the C content in the molten steel: since high carbon ferromanganese contains carbon, according to 1.6 kg high carbon ferromanganese per ton of steel to increase W[C] 0.01%, high carbon ferromanganese carbon increase amount G 高碳锰铁增碳1 = G 高碳锰铁1 ÷ 1.6 x 0.01% = 0.144 x (1.50% - W[Mn] 样1 %) ) ÷ 1.6 x 0.01% = 0.144 x (1.50% - 1.48%) ÷ 1.6 x 0.01% = 0.001%; wherein W[Mn] 目标 % is 1.50%. According to 0.13 kg carbon powder per ton of steel to increase W[C] 0.01%, remove the high carbon ferromanganese carbon increase amount G 高碳锰铁增碳1 , carbon powder input amount G 碳粉1 = 0.13 x (W[C] 目标 % - W[C] 样1 % - G 高碳锰铁增碳1 ) = 0.13 x (W[C] 目标 % - W[C] 样1 % - 0.144 x (1.50% - W[Mn] 样1 %) ÷ 1.6 x 0.01%) = 0.13 x (0.38% - 0.35% - 0.144 x (1.50% - 1.48%) ÷ 1.6 x 0.01%) = 0.36 kg / ton of steel; wherein W[C] 目标 % is 0.38%.

[0177] According to W[Cr] 样1 %: 1.87%, calculate the chromium iron addition amount, adjust the Cr content in the molten steel: according to 0.176 kg chromium iron per ton of steel to increase W[Cr] 0.001%, high carbon chromium iron input amount G 高碳铬铁1 = 0.176 x (W[Cr] 目标 % - W[Cr] 样1 %) = 0.176 x (1.90% - W[Cr] 样1%) = 0.176 × (1.90% - 1.87%) = 0.53 kg / ton of steel; where W[Cr] 目标 The percentage is 1.90%.

[0178] According to W[[Mo]] 样1 %: 0.15%, calculate the amount of ferromolybdenum added, and adjust the Mo content in the molten steel: Calculate based on an increase of W[Mo] of 0.01% for every 0.16 kg of ferromolybdenum / ton of steel, the amount of ferromolybdenum added is G. 钼铁1 =0.16×(W[Mo]) 目标 %-W[Mo] 样1 %) = 0.16 × (0.17% - W[Mo]) 样1 %)=0.16×(0.17%-0.15%)=0.32kg / ton of steel.

[0179] S46: Continue power supply to heat up until the temperature reaches the required RH temperature of 1586℃ at the station exit.

[0180] S47: Introduce 20 Nm of argon gas. 3 / h, perform temperature measurement and sampling 2. Obtain W[C] 样2 %: 0.38%, W[Si] 样2 %: 0.40%, W[Mn] 样2 %: 1.51%, W[S] 样2 %: 0.072%, W[Cr] 样2 %: 1.90%, W[Mo] 样2 %: 0.17% of element content.

[0181] S48: Passed through RH vacuum treatment.

[0182] S49: The temperature measured at the RH inlet is 1566℃.

[0183] S50: Start vacuum degassing (argon circulation, circulation flow rate 55 Nm) 3 / h), vacuum degree 0.262kPa, high vacuum time 16min, pure degassing time 13min, vacuum treatment time 19min.

[0184] S51: Introduce 7 Nm of argon gas. 3 / h, add insulating rice husks, soft blowing for 14 minutes, temperature measurement and sampling. The temperature was found to be 1532℃. W[C] was obtained. RH %: 0.38%, W[Si] RH %: 0.39%, W[Mn] RH %: 1.50%, W[S] RH %: 0.071%, W[Cr] RH %: 1.89%, W[Mo] RH%: 0.17% of the same element content.

[0185] S52: molten steel outlet, continuous casting.

[0186] Comparative Example 1

[0187] According to W[S] 样1 %: 0.015%, the amount of ferrous sulfide added was calculated to adjust the S content in the molten steel: 0.027 kg of ferrous sulfide per ton of steel was added to increase W[S] by 0.001%, and the amount of ferrous sulfide G 硫铁1 = 0.027 x (W[S] 目标 % - W[S] 样1 %) = 0.027 x (0.07% - 0.015%) = 1.49 kg / ton of steel.

[0188] W[S] 样2 %: 0.068%.

[0189] W[S] RH %: 0.067%.

[0190] Similar to the steps of Example 1, except that in the refining process, the slag sticking detection result was not considered when (TFe% + MnO%) < 1% and 2 < R < 2.2, the molten steel continued to have a certain amount of S removal, the amount of ferrous sulfide added was 1.65 kg / ton of steel, and W[S] 样2 %: 0.068% did not achieve the desired effect.

[0191] Comparative Example 2

[0192] According to experience, when the molten steel is heated to 1580°C, temperature measurement, sampling 1, and slag sticking operations are performed.

[0193] W[S] 样1 %: 0.013%.

[0194] According to W[S] 样1 %: 0.013%, the amount of ferrous sulfide added was calculated to adjust the S content in the molten steel: 0.027 kg of ferrous sulfide per ton of steel was added to increase W[S] by 0.001%, and the amount of ferrous sulfide G 硫铁1 = 0.027 x (W[S] 目标 % - W[S] 样1 %) = 0.027 x (0.07% - 0.013%) = 1.54 kg / ton of steel.

[0195] W[S] 样2 %: 0.069%.

[0196] W[S] RH %: 0.068%.

[0197] Similar to the step of example 2, the difference is only that: in the refining process, the temperature of the molten steel is not calculated accurately by the arc heating amount, and the ferrous sulfide is added when the temperature is above 1620℃. Due to the incomplete deoxidation and desulfurization reaction of the molten steel in the early stage, the ferrous sulfide is added too early to adjust the composition, resulting in a decrease in the subsequent sulfur content, the ferrous sulfide addition amount is 1.54kg / ton of steel, and W[S] 样2 %: 0.069% does not achieve the expected effect.

[0198] Comparative example 3

[0199] W[S] 样1 %: 0.009%.

[0200] The sticky slag test shows that TFe%: 0.61%, MnO%: 0.55%, and R: 1.9.

[0201] According to the increase of 0.027kg of ferrous sulfide per ton of steel, the W[S]0.001% is calculated, the ferrous sulfide input G 硫铁0 = 0.027×(W[S] 目标 %- W[S] 样1 %) = 1.65kg / ton of steel.

[0202] W[S] 样2 %: 0.074%.

[0203] W[S] RH %: 0.072%.

[0204] Similar to the step of example 3, the difference is only that: in the refining process, the molten steel will continue to have a certain amount of S return when (TFe%+MnO%)>1%, 1.8 样2 %: 0.074%, the manufacturing cost is 0.38kg / ton of steel higher, and the target composition does not achieve the expected effect.

[0205] The above is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A LF refining method of 1.2312 die steel, characterized in that, The method comprises the following steps: S1: converter tapping for deoxidizing and alloying of molten steel and slag washing; S2: argon station sampling; S3: LF refining to station, temperature measurement, T 进站 argon, fluorite ball, low alkali slag and lime were added in turn, and the slag was sent to the electric furnace. During the power supply process, the molten steel was heated to above the liquidus temperature of the steel + 80℃, and the alloy was added to adjust the C, Si, Mn, Cr, Mo content in the molten steel; S4: By accurately calculating the relationship between the total power consumption of the electric arc and the arc temperature rise, when the molten steel temperature rises to 1620℃, sample 1 is taken to obtain W[C]. 样1 %, W[Si] 样1 %, W[Mn] 样1 %, W[S]%, W[Cr] 样1 %, W[Mo] 样1 %, residue, yielding TFe% %, MnO% % and R; S5: W[C] in sample 1 样1 %, W[Si] in sample 1 样1 %, W[Mn] in sample 1 样1 %, W[Cr] in sample 1 样1 %, W[Mo] in sample 1 样 1%, calculate the alloy addition amount, adjust the chemical composition of each element to the target value, W[S] in sample 1 样1 %, and TFe%, MnO%, R to calculate the sulfur-iron alloy addition amount, and adjust the chemical composition of S element to the target value; S6: continue to supply power to heat up to the required temperature of RH, temperature measurement, sampling 2, the composition and temperature of molten steel meet the requirements, and the LF molten steel is tapped, wherein: The step S5 includes: calculating the ferrous sulphur alloy addition amount according to W[S] in sample 1 样1 % and TFe%, MnO%, R, the calculation method of the ferrous sulphur alloy addition amount is as follows: When (TFe% + MnO%) = 1% and R = 2, the content of element S in the molten steel S is stable, and there is no need to additionally increase or decrease ferrous sulphide; the input amount G of ferrous sulphide is calculated according to 0.027 kg ferrous sulphide per ton of steel for increasing W[S] 0.001% 硫铁0 = 0.027 x (W[S] 目标 % - W[S] 样1 %) / 0.001% kg / ton of steel, wherein W[S] 目标 % is 0.07%. When (TFe% + MnO%) < 1%, 2 < R < 2.2, the molten steel appears desulfurization, and the amount of sulfur-iron input G 硫铁1 = 0.027 x {W[S] 目标 % - W[S] 样1 % + W[S] 样1 % x [1 - (FeO% + MnO%) x 100] x (R - 2)} / 0.001% kg / ton steel, W[S] 目标 % is 0.07%; When (TFe% + MnO%) > 1%, 1.8 < R < 2, the molten steel appears back S condition, and the amount of sulfur and iron input G 硫铁2 = 0.027 x {W[S] 目标 % - W[S] 样1 % - W[S] 样1 % x [(FeO% + MnO%) x 100 - 1] x (2 - R)} / 0.001% kg / ton steel, W[S] 目标 % is 0.07%.

2. The LF refining process according to claim 1, characterized in that, In the step S1, the converter smelting comprises: controlling the converter tapping C at 0.10%-0.30%, controlling the P at ≤0.016%, and controlling the tapping temperature at 1630±15℃.

3. The LF refining process according to claim 1, characterized in that, In the step S1, the converter tapping alloying and slag washing treatment comprises: adding 6.1-6.4kg / ton of steel of silicon manganese, 27-28kg / ton of steel of high-carbon chromium iron at 2 / 5 of the tapping, adding 3.7-4.0kg / ton of steel of lime and 0.75-0.9kg / ton of steel of bauxite at 3 / 5 of the tapping.

4. The LF refining process of claim 1, wherein, In the step S1, when alloying and slag washing, argon gas is introduced at 60 Nm 3 / h, and after the steel is discharged, the argon gas flow is adjusted to 5-10 Nm 3 / h.

5. The LF refining process of claim 1, wherein, The step S2 comprises: sampling at argon station, obtaining W[C] 氩站 %, W[Si] 氩站 %, W[Mn] 氩站 %, W[Cr] 氩站 %, W[Mo] 氩站 %.

6. The LF refining process of claim 1, wherein, The step S3 includes: LF refining to station, temperature measurement gets T 进站 , argon 35 Nm 3 / h is passed, 11 power supply is supplied, fluorite ball 1-1.2 kg / ton steel, low alkali slag 2.3-2.4 kg / ton steel, lime 3.05-3.2 kg / ton steel is sequentially added in the power supply process, 11 power supply is converted to 4 power supply after 3 min, in the process of 4 power supply, the molten steel is heated to above the liquidus of steel + 80 DEG C, argon 45 Nm 3 / h is passed, alloy is added to adjust the content of C, Si, Mn, Cr, Mo in molten steel.

7. The LF refining process according to claim 6, characterized in that, The adding of the alloying material for adjusting the C, Si, Mn, Cr and Mo contents in the molten steel comprises: When W[C] 氩站 G = 0.13 x (W[C] 碳粉1 - W[C] 内控下限 ) / 0.01%, unit: kg / ton steel, wherein W[C] 氩站 % is 0.29%, and the carbon powder is added in three times. 内控下限 % is 0.29%, and the carbon powder is added in three times. When W[C]% 氩站 ≥ 0.29%, the amount of ferrosilicon powder G is increased by 0.136 kg / ton of steel for W[Si]0.01% 硅铁粉1 = 0.136 x (W[Si] 内控下限 %- W[Si] 氩站 %) / 0.01%, unit: kg / ton of steel, where W[Si] 内控下限 % is 0.20%, and the ferrosilicon powder is added in three times. Based on an increase of 0.01% in W[Mn] per ton of steel (0.144 kg high-carbon ferromanganese), the amount of high-carbon ferromanganese input G... 高碳锰铁0 =0.144×(W[Mn]) 内控下限 %-W[Mn] 氩站 %) / 0.01%, unit: kg / ton of steel, where W[Mn] 内控下限 The percentage is 1.45%; G = 0.176 kg high carbon ferrochrome per ton of steel 高碳铬 Fe = 0.176 x (W[Cr] lower limit % - W[Cr] argon station %) / 0.001 %, in kg per ton of steel, where W[Cr] lower limit % is 0.001 % and W[Cr] argon station % is 0.001 %. 控下限 W[Cr] = 0.001 % + 0.176 x (Fe - 0.176) / 0.001 % = 0.001 % + 0.176 x Fe W[Cr] = 0.001 % + 0.176 x Fe W[Cr] = 0.001 % + 0.176 x Fe W[Cr] = 0.001 % + 0.176 x Fe W[Cr] = 0 Based on an increase of 0.01% in W[Mo] per ton of steel (0.16 kg ferromolybdenum), the amount of ferromolybdenum input G... 钼铁0 =0.16×(W[Mo]) 内控下限 %-W[Mo] 氩站 %) / 0.01%, unit: kg / ton of steel, where W[Mo] 内控下限 The percentage is 0.16%.

8. The LF refining process of claim 1, wherein, The step S4 includes: molten steel entering into the station and being heated to 1620℃, total electric energy consumption Q of the electric arc = electric arc heating amount K x 33 x 0.6 = [1620-T 进站 +(△T 渣料 +△T 合金 )÷0.8 x 2] x 33 x 0.6, the unit of the total electric energy consumption Q is kWh, wherein T 进站 is the LF entering temperature, △T 渣料 is the slag adding temperature drop, △T 合金 is the alloy adding temperature drop, T 进站 , △T 渣料 , △T 合金 all have the unit of ℃.

9. The LF refining process of claim 1, wherein, The step S5 comprises: adding silicon iron powder, high-carbon chromium iron and molybdenum iron to adjust the Si, Cr and Mo contents in the molten steel; Based on an increase of 0.01% in W[Si] per ton of steel using 0.14 kg of ferrosilicon powder, the amount of ferrosilicon powder input G... 硅铁1 =0.14×(W[Si]) 目标 %-W[Si] 样1 %+S 样1后升温 (÷5×0.01%) / 0.01%, unit: kg / ton of steel; where, silicon loss △W[Si] 损失 % = S 样1后升温 ÷5×0.01%, where S 样1后升温 W[Si] represents the heating time (in minutes) after sample 1 is taken. 目标 The percentage is 0.40%; G = 0.176 kg high carbon ferrochrome per ton of steel increase W[Cr] 0.001% calculated 高碳铬 Fe 1 = 0.176 x (W[Cr] target% - W[Cr] sample 1%) / 0.01%, where W[Cr] target% is 1.90%; Based on an increase of 0.01% in W[Mo] per ton of steel (0.16 kg ferromolybdenum), the amount of ferromolybdenum input G... 钼铁1 =0.16×(W[Mo]) 目标 %-W[Mo] 样1 %) / 0.01%, where W[Mo] 目标 The percentage is 0.17%.

10. The LF refining process of claim 1, wherein, The step S5 comprises: adding high-carbon manganese iron and carbon powder to adjust the Mn and C contents in the molten steel; Based on an increase of 0.01% in W[Mn] per ton of steel (0.144 kg high-carbon ferromanganese), the amount of high-carbon ferromanganese input G... 高碳锰铁1 =0.144×(W[Mn]) 目标 %-W[Mn] 样1 %) / 0.01%, unit: kg / ton of steel, where W[Mn] 目标 The percentage is 1.50%; Based on an increase of 0.01% in W[C] per ton of steel (1.6 kg of high-carbon ferromanganese), the carbon increase G in high-carbon ferromanganese is... 高碳锰铁增碳1 =0.144×(W[Mn]) 目标 %-W[Mn] 样1 %)÷1.6, unit: kg / ton of steel, where W[Mn] 目标 The percentage is 1.50%; Based on an increase of 0.01% in W[C] for every 0.13 kg of carbon powder per ton of steel, the amount of carbon powder input G... 碳粉1 =0.13×(W[C]) 目标 %-W[C] 样1 % -0.144 × (W[Mn]) 目标 %-W[Mn] 样1 (%)÷1.6), unit: kg / ton of steel, where W[C] 目标 The percentage is 0.38%.

11. The LF refining process of claim 1, wherein, The step S6 includes: according to the detection result of sample 1, after adjusting the chemical composition requirements of each element to the target value, continuing to supply power to warm up to the required temperature of the outlet RH, introducing argon 20 Nm 3 / h, temperature measurement, sample 2, and obtaining W[C] 样2 %, W[Si] 样2 %, W[Mn] 样2 %, W[S] 样2 %, W[Cr] 样2 %, W[Mo] 样2 % element content, composition, temperature meet the requirements, LF molten steel outlet.