Producing method of clean steel

A production method and clean steel technology, applied in the manufacture of converters, etc., can solve the problem of low cleanliness and achieve the effect of improving cleanliness

Inactive Publication Date: 2011-01-26
PANGANG GROUP VANADIUM TITANIUM & RESOURCES +3
View PDF6 Cites 64 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] In order to overcome the deficiency that the cleanliness of the existing clean steel is still low, the technical problem to be solved by the present invention is to provide a clean steel production method that can further improve the cleanliness

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0041] The molten iron is sprayed and desulfurized by using a mixed magnesium desulfurizer in the pretreatment desulfurization station, and the desulfurization slag is removed by a slag scraper after desulfurization. After the molten iron is pretreated for desulfurization, the S in the molten iron is reduced from 0.060% to S≤0.010% by weight percentage. When the 80t converter is smelted with vanadium-containing molten iron after desulfurization, add molten iron, start blowing with oxygen lance and add 20kg / t steel active lime, 4kg / t steel steelmaking sludge balls, and add composite slagging agent 3.75 kg / t steel, the position of the oxygen blowing lance is controlled at 1.2-1.6m. In oxygen blowing volume 20~30Nm 3 / t steel, when the temperature is 1400°C, stop blowing, and remove the formed slag from the converter mouth to the slag pot as much as possible, the formed slag alkalinity CaO / SiO 2 = 2.2, the main components (wt%) are TFe12%, P1.0%, the slag removal rate is 50%-70...

Embodiment 2

[0050] The molten iron is sprayed and desulfurized by using a mixed magnesium desulfurizer in the pretreatment desulfurization station, and the desulfurization slag is removed by a slag scraper after desulfurization. After the molten iron is pretreated for desulfurization, [S] in the molten iron is reduced from 0.070% to [S]≤0.010% by weight percentage. When the 80t converter is smelted with vanadium-containing molten iron, add molten iron, start blowing with oxygen lance, add 25kg / t steel active lime, 5.5kg / t steel steelmaking sludge balls, and add composite slagging agent 3.75kg / t steel, the position of the oxygen blowing lance is controlled at 1.2-1.6m. In oxygen blowing volume 20~30Nm 3 / t steel, when the temperature is 1430°C, stop blowing, and remove the formed slag from the converter mouth to the slag pot as much as possible. The basicity of the formed slag R=CaO / SiO 2 =2.5, the main components (wt%) are TFe14%, P1.2%, slag removal 50%-70%, so that slag removal P acc...

Embodiment 3

[0059] In practice, molten iron is sprayed and desulfurized by using a mixed magnesium desulfurizer at the pretreatment desulfurization station, and after desulfurization, a slag scraper is used to remove the desulfurized slag. The molten iron [S] is reduced from 0.080% to [S]≤0.010% after molten iron pretreatment and desulfurization. When the 80t converter is smelted with vanadium-containing molten iron, add the molten iron, start blowing with the oxygen lance and add 30kg / t steel active lime, 7kg / t steel steelmaking sludge balls, and add a composite slagging agent 3.75 kg / t steel, the position of the oxygen blowing lance is controlled at 1.2-1.6m. In oxygen blowing volume 20~30Nm 3 / t steel, when the temperature is 1460°C, stop blowing, and remove the formed slag from the converter mouth to the slag pot as much as possible. The basicity of the formed slag (CaO / SiO 2 ) 2.8, the main components (wt%) are TFe16%, P1.4%, the slag removal amount is 50%-70%, so that the slag re...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
melting pointaaaaaaaaaa
Login to view more

Abstract

The invention discloses a producing method of clean steel, which can further enhance the cleanliness and comprise the following steps of: pretreating with molten iron for desulfurizing until [S] is not more than 0.010%; then delivering to a converter for smelting; dephosphorizing and controlling sulfur; controlling finished molten iron in the converter to be with [P] of not more than 0.0080% and [S] not more than 0.010%; adding a ladle slag modifying agent to ladles in a steel tapping process for regulating and modifying the ladle slag, wherein after treating, in the molten iron, [P] is not more than 0.0060% to 0.0080%, [S] is not more than 0.0080% and roughing slag quantity is not more than 0.5%; controlling refined finished slag components in LF (Low Frequency) refining, wherein soft argon blowing time of the molten iron is not less than 5 minutes after LF refining, and the composition is qualified when [S] is not more than 0.0020%; carrying out VD (Vacuum Degassing) refining to ensure that [H] is not more than 1.5ppm; and continuously casting, wherein a double-layer high-alkalinity covering agent is adopted as a middle ladle, a seal ring and a long water gap are additionally arranged for argon-blowing protective casting, which is carried out at constant speed, and overheat delta T of the molten iron ranged from 15 DEG C to 30 DEG C. Under the condition that the producing cost is not increased basically, the cleanliness of the clean steel is further enhanced by the control of each procedure junction point, and the clean steel comprises the following components by weight percent: S not more than 20ppm, P not more than 100ppm, TO not more than18ppm, H smaller than 2.0ppm, N not more than 35ppm, and A, B, C and D types of impurities not more than 0.5 grade.

Description

technical field [0001] The invention relates to a steelmaking method, in particular to a clean steel production method. Background technique [0002] "Clean steel" refers to a class of steel products that have very low levels of oxide and sulphide inclusions. The term now also refers to steels that are low in phosphorus, hydrogen, nitrogen, and sometimes carbon. Regarding the production method of clean steel, many manufacturers are secretive. [0003] The Chinese patent application document published on March 10, 2004 with the publication number CN1480549 discloses a barium-containing clean steel and its production method. The invention belongs to the field of alloy steel, and in particular relates to barium-containing alloy steel. The barium-containing clean steel of the invention is produced after being melted in a conventional electric furnace, converter or other non-vacuum melting furnace, then refined in a refining device, and barium alloying is carried out in the late...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C21C5/28C21C7/00
Inventor 王建陈永曾建华何为戈文荪康斌成海涛周永健张永军张珉滕建明易良刚陈坤严加琪余海滨
Owner PANGANG GROUP VANADIUM TITANIUM & RESOURCES
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products