A method for reducing transverse cracks in niobium-containing steel corners

A transverse crack, niobium steel technology, applied in the field of continuous steel casting in the metallurgical industry, can solve the problems of difficulty in eliminating transverse cracks at the corners, low niobium content, affecting the quality of niobium-containing steel, etc. Effects of transverse cracks on corners of niobium-containing steel and enhanced solidification uniformity

Active Publication Date: 2017-03-01
SHOUGANG CORPORATION
View PDF6 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In order to solve the problem of transverse cracks at the corner of the slab, domestic and foreign enterprises have adjusted the composition of molten steel and optimized the cooling process of the secondary cooling section, etc., but the effect is not obvious
In order to solve the problem of transverse cracks at the corners of the slab, in recent years, some slab continuous casting molds have begun to use chamfered molds for production, but because the solidification characteristics of the metal in the mold are not clear, the designed chamfered mold structure is not Reasonable and poor matching of process parameters, so it can only solve the problem of corner cracks in niobium-containing steel with low niobium content
For niobium-containing steels with high niobium content (such as niobium content greater than or equal to 0.035%), the corner transverse cracks are still difficult to eliminate, which seriously affects the quality of niobium-containing 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
  • A method for reducing transverse cracks in niobium-containing steel corners
  • A method for reducing transverse cracks in niobium-containing steel corners
  • A method for reducing transverse cracks in niobium-containing steel corners

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] A steel mill casts a 230×1600mm medium-carbon niobium-containing continuous casting slab by using the method for reducing transverse cracks at the corners of niobium-containing steel provided by the embodiment of the present invention.

[0032] During the production process, the C content in molten steel is controlled to be 0.018%, and the Nb content is controlled to be 0.03%. The narrow side of the crystallizer is a double-taper crystallizer with a distance of 350mm from the upper mouth. The taper of the upper mouth of the mold is controlled at 1.46%, and the taper of the lower mouth of the mold is controlled at 1.0%. The flow velocity in the crystallizer wide surface and narrow surface water tank is controlled to be 8.7m / s and 8.4m / s respectively. The specific water volume of the secondary cooling zone is controlled at 0.73L / kg, and the ratio of the total water volume of cooling water in zones 2-4 to the total water volume of cooling water in zones 6-8 is 0.6. The me...

Embodiment 2

[0035]A steel mill casts a 230×1600mm medium-carbon niobium-containing continuous casting slab by using the method for reducing transverse cracks at the corners of niobium-containing steel provided by the embodiment of the present invention.

[0036] In the production process, the C content in the molten steel is controlled at 0.085%, the Nb content is controlled at 0.06%, the narrow surface of the crystallizer is a double-taper mold with a distance of 350mm from the upper mouth, the taper of the upper mouth of the mold is controlled at 1.56%, and the lower mold Mouth taper is controlled at 1.1%. The flow velocity in the crystallizer wide surface and narrow surface water tank is controlled to be 8.7m / s and 7.8m / s respectively. The specific water volume of the secondary cooling zone is controlled at 0.68L / kg, and the ratio of the total water volume of cooling water in zones 2-4 to the total water volume of cooling water in zones 6-8 is 0.65. The melting point of mold flux is c...

Embodiment 3

[0039] A steel mill casts a 230×1400mm continuous casting slab of niobium-containing steel by using the method for reducing transverse cracks at the corners of niobium-containing steel provided by the embodiment of the present invention.

[0040] In the production process, the C content in the molten steel is controlled at 0.07%, the Nb content is controlled at 0.05%, the narrow surface of the crystallizer is a double-taper mold with a distance of 350mm from the upper mouth, the taper of the upper mouth of the mold is controlled at 1.56%, and the lower mold Mouth taper is controlled at 1.1%. The flow velocity in the water tank on the wide side and the narrow side of the crystallizer is controlled in the range of 8.7m / s and 8.4m / s respectively. The specific water volume in the secondary cooling zone is controlled at 0.70L / kg, and the ratio of the total water volume of cooling water in zones 2-4 to the total water volume of cooling water in zone 6-8 is 0.7; the melting point of ...

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 relates to the field of continuous casting in a metallurgical industry, in particular to a method of reducing cross cracks at a niobium-containing steel angle part. The method comprises the steps of manufacturing niobium-containing steel by adopting a chamfer crystallizer of which a narrow surface is of a double-cone angle; controlling the N content of molten steel to be not more than 50ppm and the Nb content to be not more than 0.12%; controlling the water flow in a wide water tank of the crystallizer to be more than that in a narrow water tank; controlling the specific water flow of the secondary cooling zone to be 0.55-0.80L / t by adopting a cooling casting blank of a secondary cooling zone; controlling the specific value of the total water of cooling water in second to fourth areas to the total water of cooling water in sixth to eighth area to be 0.6-1.0; controlling the water inlet temperature of the crystallizer to be 28-32 DEG C; controlling the degree of superheat of the crystallizer to be in a narrow range of degree of superheat, and controlling the melting point of casting powder in the crystallizer to be not more than 1150 DEG; controlling the viscosity of the molten steel in the crystallizer to be not more than 0.140pa.s (viscosity value at 1300 DEG C). According to the method of reducing cross cracks at the niobium-containing steel angle part provided by the invention, the problems of being easy to generate cross cracks at the niobium-containing steel angle part of which the Nb content is not more than 0.12% can be solved well.

Description

technical field [0001] The invention relates to the field of continuous steel casting in the metallurgical industry, in particular to a method for reducing transverse cracks at corners of niobium-containing steel. Background technique [0002] With the development of continuous casting technology, the slab continuous casting production line needs to produce high-quality steel grades, and the niobium content in cast steel is gradually increasing, which is prone to corner transverse cracks. In order to solve the problem of transverse cracks at the corners of the slab, domestic and foreign enterprises have adjusted the composition of molten steel and optimized the cooling process of the secondary cooling section, but the effect is not obvious. In order to solve the problem of transverse cracks at the corners of the slab, in recent years, some slab continuous casting molds have begun to use chamfered molds for production, but because the solidification characteristics of the met...

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 Patents(China)
IPC IPC(8): B22D11/22B22D11/059
Inventor 刘国梁陈斌包春林季晨曦罗衍昭彭开玉张颖华马威李中华张丽丽
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