Method for producing silicon steel normalizing substrate

Patent metadata

Field	Value
Publication number	US-9738946-B2
Application number	US-201214379595-A
Country	US
Kind code	B2
Filing date	Mar 27, 2012
Priority date	Mar 8, 2012
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

A method for producing a silicon steel normalizing substrate comprises steelmaking, hot rolling and normalizing steps. A normalizing furnace is used in the normalizing step, and along a moving direction of strip steel, the normalizing furnace sequentially comprises: a preheating section, a nonoxidizing heating section, a furnace throat, furnace sections for subsequent normalizing processing, and a delivery seal chamber. Furnace pressures of the normalizing furnace are distributed as follows: the furnace pressure of a downstream furnace section adjacent to the furnace throat along the moving direction of the strip steel is the highest, the furnace pressure decreases gradually from the furnace section with the highest furnace pressure to a furnace section in an inlet direction of the normalizing furnace, and the furnace pressure decreases gradually from the furnace section with the highest furnace pressure to a furnace section in an outlet direction of the normalizing furnace.

First claim

The invention claimed is:

1. A method for producing normalized silicon steel substrates, comprising steps of steelmaking, hot rolling, and normalizing, wherein a normalizing furnace is used in the normalizing step and comprises sequentially, along the running direction of the strip steel, preheating section, non-oxidation heating section, tunnel seal, multiple subsequent normalizing treatment furnace sections, and exit sealing device, wherein the normalizing furnace has a pressure distribution as follows: the furnace pressure reaches its maximum at the downstream furnace section adjacent to the tunnel seal along the running direction of the strip steel, said furnace pressure gradually declines from the furnace section having the maximum pressure to the furnace sections toward the inlet of the normalizing furnace, and gradually declines from the furnace section having the maximum pressure to the furnace sections toward the outlet of the normalizing furnace.

2. The method of claim 1 , wherein said multiple subsequent normalizing treatment furnace sections include at least one furnace section selected from the group consisting of radiant tube heating/cooling section, electric/radiant tube soaking section, and radiant tube/water jacket cooling section, and wherein said multiple subsequent normalizing treatment furnace sections are arranged in a random sequence.

3. The method of claim 1 , wherein protective gas of N 2 is charged into the furnace sections between tunnel seal and exit sealing device, and a supply of the protective gas of N 2 to the furnace sections between the tunnel seal and exit sealing device is adjusted so as to realize said distribution of furnace pressure.

4. The method of claim 3 , wherein the supply of the protective gas of N 2 to said furnace sections satisfies the following relation:
N 2 supply at tunnel seal/total N 2 supply at multiple subsequent normalizing treatment furnace sections≧1.2.

5. The method of claim 1 , wherein said distribution of furnace pressure has a furnace pressure difference controlled in the range from 0 to 10 Pa between the downstream furnace section adjacent to the tunnel seal along the running direction of the strip steel and the non-oxidation heating section.

6. The method of claim 5 , wherein said furnace pressure difference is controlled in the range from 5 to 10 Pa.

7. The method of claim 1 , wherein said distribution of furnace pressure has a benchmark for furnace pressure control set in the range from 10 to 25 Pa.

8. The method of claim 1 , wherein in said distribution of furnace pressure, the slope of furnace pressure reduction from the downstream furnace section adjacent to the tunnel seal along the running direction of the strip steel to the furnace sections toward the outlet of the normalizing furnace is between −0.05 and −0.25, and wherein the slope of furnace pressure reduction from the non-oxidation heating section to the furnace sections toward the inlet of the normalizing furnace is between 0.55 and 0.8.

Assignees

• Hei Hongxu
• Chen Xiao
• Liu Xiandong
• Xie Shishu
• Su Dejun
• Lin Runjie
• Zhang Peili
• Jiang Rongqiang
• Ye Miao
• Baoshan Iron & Steel

Inventors

• Hei Hongxu
• Chen Xiao
• Liu Xiandong
• Xie Shishu
• Su Dejun
• Lin Runjie
• Zhang Peili
• Jiang Rongqiang
• Ye Miao

Classifications

• C21D8/1261 Primary

  following hot rolling · CPC title

• C21D1/28

  Normalising · CPC title

• C21D9/561

  with a controlled atmosphere or vacuum · CPC title

• H01F41/00

  Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties · CPC title

• C21D1/34

  Methods of heating (C21D1/06 takes precedence) · CPC title