Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for reducing nitrogen content of welding steel wire rod

A technology for welding steel and nitrogen content, which is applied in the field of smelting production technology, can solve problems such as fracture, high cost, and large drawing volume, and achieve the effects of simple process lines, reduced processing costs, and low production costs

Active Publication Date: 2013-09-04
WUHAN IRON & STEEL GRP ECHENG IRON & STEEL CO LTD
View PDF4 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the steel produced by the traditional electric furnace smelting process has a high nitrogen content, and the steel with high nitrogen content has poor plasticity, toughness and rolling performance, and the steel wire rod for welding has a large amount of drawing during cold processing , prone to drawing cracks or even fractures, directly affecting welding quality and welding performance
[0004] Many manufacturers in China have N removal methods, but most of them are for medium and high carbon and converter smelting, while there are fewer N removal methods for the production of low-carbon and low-sulfur steel in electric furnaces, and the process is more complicated and costly. also relatively high

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 reducing nitrogen content of welding steel wire rod

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] 1) High-quality welding steel wire rods are smelted and produced by low-level electrocardiographic furnace → LF refining furnace → continuous casting process.

[0029] 2) The charging capacity of primary smelting furnace is 72 tons, using the combination of molten iron + scrap steel, of which the amount of molten iron is 64t; the composition and temperature control requirements of the end point of electric furnace tapping: C: 0.04%, P: 0.06%, N: 60ppm, tapping Temperature: T=1620°C; 60kg of aluminum ingots and 800kg of active lime are added during tapping, and slag is strictly prohibited during tapping.

[0030] 3) Add 1000kg manganese metal and 450kg ferromolybdenum before the molten steel enters the refining furnace after tapping.

[0031] 4) In order to reduce the amount of nitrogen absorbed by molten steel, after entering the refining furnace, first add 500kg of active lime, then add 200kg of fluorite, and finally add 90kg of Al pellets; heat at 1540°C for 7 minutes...

Embodiment 2

[0038] 1) High-quality welding steel wire rods are smelted and produced by low-level electrocardiographic furnace → LF refining furnace → continuous casting process.

[0039] 2) The charging capacity of the primary furnace is 75 tons, using the combination of molten iron + scrap steel, of which the amount of molten iron is 63t; the composition and temperature control requirements of the end point of electric furnace tapping: C: 0.04%, P: 0.05%, N: 58ppm, tapping Temperature: T=1634°C; 65kg of aluminum ingots and 800kg of active lime are added during tapping, and slag is strictly prohibited during tapping.

[0040] 3) Add 1000kg manganese metal and 450kg ferromolybdenum before the molten steel enters the refining furnace after tapping;

[0041] 4) In order to reduce the amount of nitrogen absorbed by molten steel, after entering the refining furnace, first add 500kg of active lime, then add 200kg of fluorite, and finally add 90kg of Al pellets; heat at 1540°C for 7 minutes; the...

Embodiment 3

[0048] 1) High-quality welding steel wire rods are smelted and produced by low-level electrocardiographic furnace → LF refining furnace → continuous casting process.

[0049] 2) The charging capacity of the primary furnace is 76 tons, and the combination of molten iron and scrap steel is adopted, of which the amount of molten iron is 62t; the composition and temperature control requirements of the end point of electric furnace tapping: C: 0.03%, P: 0.06%, N: 54ppm, tapping Temperature: T=1641°C; 68kg of aluminum ingots and 600kg of active lime are added during tapping, and slag is strictly prohibited during tapping.

[0050] 3) Add 1000kg manganese metal and 450kg ferromolybdenum before the molten steel enters the refining furnace after tapping;

[0051] 4) In order to reduce the amount of nitrogen absorbed by molten steel, after entering the refining furnace, first add 500kg of active lime, then add 150kg of fluorite, and finally add 110kg of Al pellets; heat at 1540°C for 14...

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

No PUM Login to View More

Abstract

The invention discloses a method for reducing the nitrogen content of a welding steel wire rod. The method comprises the following steps of: treating the combination of molten iron and waste steel in a primary refining electric furnace, wherein the molten iron accounts for more than 70 percent; tapping at the temperature of between 1,620 and 1,650 DEG C; adding 10 to 20 kg / ton of metallic manganese and 4 to 10 kg / ton of ferromolybdenum into the molten steel after tapping, and delivering the mixture to a refining furnace; after the mixture is delivered to the low frequency (LF) refining furnace, sequentially adding a first batch of slag and a second batch of slag; after the slag becomes white, performing fine adjustment of alloy in the LF refining furnace to prevent nitrogen absorption caused by the naked molten steel in the ladle hoisting process, and finally adding 1 to 2 kg / ton of powdery carbon-free covering agent; and preventing the molten steel from absorbing nitrogen by using a fiber sealing ring during continuous casting. The method is simple in process route, strong in operability and easy to control.

Description

technical field [0001] The invention relates to a smelting production process for producing high-purity welding wire steel by an electric furnace in the metallurgical industry, in particular to a method for reducing nitrogen content in a welding steel wire rod. Background technique [0002] With the development of metallurgical technology, the content of other impurity elements such as oxygen, sulfur, hydrogen, etc. can be removed to a very low level. However, denitrification is not an easy task. The ionic radius of nitrogen is larger than that of hydrogen, and the diffusion coefficient in steel is two orders of magnitude smaller than that of hydrogen. The effect of vacuum dehydrogenation is very good, but vacuum is not good for denitrification. So easy, nitrogen is not as active as oxygen, and can form inclusions with strong deoxidizers such as aluminum, barium, silicon, etc., and be removed by floating; while nitrogen is much less active, and nitrides formed with most allo...

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
IPC IPC(8): C21C7/076C21C5/52
CPCY02P10/20
Inventor 黄海玲陈庆丰张贤忠杨帆陈华强李嘉伟何建勋
Owner WUHAN IRON & STEEL GRP ECHENG IRON & STEEL CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com