Method for controlling non-metallic inclusion in pipeline steel

A technology for non-metallic inclusions and inclusions, which is applied in the field of steelmaking and refining control, can solve problems such as jeopardizing the performance of pipeline steel, and achieve the effect of good deoxidation and avoidance of cracks.

Active Publication Date: 2009-07-29
SHOUGANG CORPORATION
View PDF0 Cites 18 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a method for controlling inclusions in pipeline steel, which solves the problem of inclusions that endanger the performance of pipeline steel

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for controlling non-metallic inclusion in pipeline steel
  • Method for controlling non-metallic inclusion in pipeline steel
  • Method for controlling non-metallic inclusion in pipeline steel

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0016] Embodiment (10 heats test results)

[0017] 210 tons of oxygen re-blown converter, 800kg of aluminum and iron (aluminum content: 40wt%), 1600kg of lime, and 400kg of fluorite are added during the tapping process of the converter. After tapping, the molten steel aluminum content is 0.030wt%,

[0018] The LF refining was completed after 11 minutes of slag reduction. The slag components were CaO: 55.8wt%, MgO: 8.0wt%, Al2O3: 29.8wt%, SiO2: 5.3wt%, TFe: 0.46wt%, MnO: 0.15wt%.

[0019] After slagging, carry out bottom blowing Ar strong stirring desulfurization, the bottom blowing intensity is 1000Nl / min, and the bottom blowing time is 15 minutes. After desulfurization by bottom blowing and strong stirring, the sulfur content of molten steel is 0.0008wt%, [Mg]: 0.0005wt%, [Ca]: 0.0007wt% in molten steel.

[0020] After RH vacuum treatment for 20 minutes, feed Si-Ca wire for Ca treatment. The total amount of Ca added to the wire is 18kg. After feeding the wire, carry out sof...

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
melting pointaaaaaaaaaa
melting pointaaaaaaaaaa
Login to view more

Abstract

A method for controlling non-metal inclusions in pipe line steel belongs to the refining controlling field of steel making. The method comprises a step of controlling the following chemical components of non-metal inclusions of oxides in pipe line steel casts: 20wt%-35wt% of CaO, 10wt%-20wt% of MgO, 30wt%-60wt% of Al2O3 and not more than 5wt% of others. Sulfide inclusions in the pipe line steel casts comprise 90wt%-100wt% of CaS and not more than 10wt% of others, and no MnS inclusion exists in the pipe line steel casts. In the LF refining process, reaction between molten steel and high-alkalinity furnace slag is used to control contents of Ca, Mg and S in the molten steel, and Ca dosage in the calcium treatment process, so as to control melting point of the non-metal inclusions in the molten steel to be between 1500 DEG C and 1650 DEG C. The method has the advantage that deformation index of the non-metal inclusions in post rolling process is controlled to be not more than 0.5 while good oxidizing and desulfurizing effects of the molten steel are achieved, thus avoiding cracks caused in use process of the pipe line steel by linear or stripe-shaped non-metal inclusions after being rolled.

Description

technical field [0001] The invention belongs to the technical field of steelmaking and refining control. In particular, it relates to the control method of non-metallic inclusions in pipeline steel. Background technique [0002] Pipeline steel is mainly used to transport oil, natural gas, etc. In addition to high strength and low-temperature impact performance, it also requires high non-metallic inclusions in the steel during use, and deformation such as MnS is not allowed in pipeline steel. inclusions. If there are deformed inclusions, during the rolling process, the non-metallic inclusions will deform with the deformation of the steel matrix, and will form linear or strip-shaped inclusions parallel to the rolling direction. It can become a source of cracks during use. [0003] Since S is a strong segregating element, MnS inclusions are easily formed during solidification. At present, when producing pipeline steel at home and abroad, the method of Ca treatment is mainly...

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): C21C7/04C21C7/076C21C7/064
CPCY02P10/20
Inventor 朱国森王新华李海波刘建辉李强李明周德光亢小敏
Owner SHOUGANG CORPORATION
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap