CN102409148A - Controlled cooling method of L450MB pipeline steel - Google Patents
Controlled cooling method of L450MB pipeline steel Download PDFInfo
- Publication number
- CN102409148A CN102409148A CN2010102917515A CN201010291751A CN102409148A CN 102409148 A CN102409148 A CN 102409148A CN 2010102917515 A CN2010102917515 A CN 2010102917515A CN 201010291751 A CN201010291751 A CN 201010291751A CN 102409148 A CN102409148 A CN 102409148A
- Authority
- CN
- China
- Prior art keywords
- cooling
- steel plate
- l450mb
- controlled
- pipe line
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Heat Treatment Of Steel (AREA)
Abstract
The invention provides a controlled cooling method of a L450MB pipeline steel. A sectional type controlled cooling mode combined of fast cooling and air cooling are employed, after finish the rolling, steel plate is rapidly cooled by a large cooling rate of 30-40 DEG C/s to the ferrite phase transition temperature scope, air cooling is carried out for 4-10s, steel plate is rapidly cooled by a small cooling rate of 5-10 DEG C/s to the target final cooling temperature. The air cooling of steel plate in critical temperature range of the ferrite transformation is in favor of fully precipitation and the growth of the ferrite crystal grain, the size and distribution of ferrite crystal grain tend to uniformization and equiaxial, pearlitic pellet gets smaller and tends to dispersion and distribution, thereby an ideal tissue state and good comprehensive mechanical property can be obtained. Plastic strain ratio R and the strain hardening index n are increased, the cold-forming performance is improved, the yield ratio of the L450 MB steel plate is reduced, the shape of the steel plate after controlled cooling is improved, and the original type rolling yield of the steel plate is increased.
Description
Technical field
The invention belongs to the steel rolling process field, particularly a kind of controlled chilling method that is used to reduce L450MB pipe line steel yield tensile ratio.
Background technology
So-called L450MB pipe line steel, the weight percent content of the chemical ingredients of approval is in the world at present: C≤0.12%, Si≤0.45%, Mn≤1.60%, P≤0.025%, S≤0.015%, V≤0.15%, Nb≤0.15%, Ti≤0.15%; Nb+V+Ti≤0.15% wherein.What domestic L450MB pipe line steel generally adopted is that traditional ACC is controlled cold pattern; Promptly select cooling jig automatically according to steel grade, rolled piece thickness, detected rolled piece temperature and target cooling temperature; And send instruction; Open sealing gland and upper and lower collector valve successively, adopt continous way fixedly the mode of rate of cooling rolled piece is cooled off valve-off successively again after rolled piece passes through.This is controlled the pipe line steel of producing under the cold pattern and is easy to generate shape wave, and it is relatively poor to control cold back plate property homogeneity, the Properties Control ability a little less than, the ys fluctuation is bigger.Thereby make pipe line steel because the overproof stock rate that causes of yield tensile ratio is bigger, directly influence the prestige and the economic benefit of enterprise.
Summary of the invention
The object of the invention is exactly in order to overcome above-mentioned defective, provides a kind of simple, is convenient to operation, can obtain more satisfactory interior tissue, effectively controls the fluctuation of L450MB pipeline steel plate ys, improves the controlled chilling method of the former kind lumber recovery of steel plate.For this reason, the technical scheme that the present invention taked is:
A kind of controlled cooling method of L450MB pipe line steel adopts cold soon, air cooling bonded sectional controlled chilling mode, reduces L450MB pipe line steel yield tensile ratio, and its concrete grammar is:
After the finish to gauge, steel plate is quickly cooled in the ferrite transformation temperature province with big rate of cooling, in air, after the of short duration cooling, with little rate of cooling steel plate is quickly cooled to the target final cooling temperature again.
Said big rate of cooling is 30～40 ℃/s.
Said little rate of cooling is 5～10 ℃/s.
Said in air of short duration cooling time be 4～10s.
Positively effect of the present invention is:
Owing to adopt cold soon, air cooling bonded sectional controlled cooling method; Realized air cooling in the critical temperature interval of ferritic transformation; Help ferritic fully separate out with after the tiny ferrite crystal grain of separating out grow up; Thereby ferritic percentage composition is increased, and the size distribution of ferrite crystal grain is tending towards homogenizing and isometry.Though ferrite grain size has increase slightly; But the increase of ferrite content will make pearlitic percentage composition significantly reduce; The perlite pelletizing diminishes and is tending towards disperse and distributes, thereby obtains more satisfactory structural state and good comprehensive mechanical properties, wherein; The conventional leading portion cooling of plastic strain ratio R and strain-hardening index n value increases, and this is favourable to the cold forming capability that improves the L450MB pipe line steel.Simultaneously, the fluctuation of steel plate ys has effectively been controlled in the improvement of steel plate microtexture, has reduced the steel plate yield tensile ratio, has improved the plate shape after the steel plate control is cold, has improved the former kind lumber recovery of steel plate.
Embodiment
The present invention's L450MB pipe line steel controlled cooling method mainly is through cold, the cold mode of air cooling bonded sectional control soon, obtains comparatively ideal grain structure, thereby reduces the yield tensile ratio of L450MB pipe line steel.
Embodiment 1:
The L450MB pipe line steel, the weight percent content of its chemical ingredients is: C 0.11%, and Si 0.35%, and Mn 1.20%, P≤0.020%, S≤0.015%, V 0.04%, and Ti 0.09%.
Adopt the method for controlled rolling in the operation of rolling; After the finish to gauge the big rate of cooling of steel plate with 40 ℃/s is quickly cooled in the ferrite transformation temperature province; In air behind the air cooling 4s; Little rate of cooling with 10 ℃/s is quickly cooled to the target final cooling temperature with steel plate again, thereby obtains more satisfactory internal crystallization tissue, reduces the steel plate ys.
Embodiment 2
The L450MB pipe line steel, the weight percent content of its chemical ingredients is: C 0.08%, and Si 0.45%, and Mn 1.50%, P≤0.015%, S≤0.010%, V 0.08%, and Nb 0.05%.
Adopt the method for controlled rolling in the operation of rolling; After the finish to gauge the big rate of cooling of steel plate with 30 ℃/s is quickly cooled in the ferrite transformation temperature province; In air behind the air cooling 8s; Little rate of cooling with 6 ℃/s is quickly cooled to the target final cooling temperature with steel plate again, thereby effectively controls the fluctuation of steel plate ys, reduces the steel plate ys.
Claims (4)
1. the controlled cooling method of a L450MB pipe line steel is characterized in that, adopts cold soon, air cooling bonded sectional controlled chilling mode, reduces L450MB pipe line steel yield tensile ratio, and its concrete grammar is:
After the finish to gauge, steel plate is quickly cooled in the ferrite transformation temperature province with big rate of cooling, in air, after the of short duration cooling, with little rate of cooling steel plate is quickly cooled to the target final cooling temperature again.
2. L450MB pipe line steel controlled cooling method according to claim 1 is characterized in that said big rate of cooling is 30～40 ℃/s.
3. L450MB pipe line steel controlled cooling method according to claim 1 is characterized in that said little rate of cooling is 5～10 ℃/s.
4. L450MB pipe line steel controlled cooling method according to claim 1 is characterized in that, be 4～10s of short duration cooling time in air.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010102917515A CN102409148A (en) | 2010-09-26 | 2010-09-26 | Controlled cooling method of L450MB pipeline steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010102917515A CN102409148A (en) | 2010-09-26 | 2010-09-26 | Controlled cooling method of L450MB pipeline steel |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102409148A true CN102409148A (en) | 2012-04-11 |
Family
ID=45911487
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010102917515A Pending CN102409148A (en) | 2010-09-26 | 2010-09-26 | Controlled cooling method of L450MB pipeline steel |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102409148A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103627869A (en) * | 2013-12-06 | 2014-03-12 | 攀钢集团西昌钢钒有限公司 | After-rolling controlled cooling process and preparation method of pipeline steel with low yield ratio |
| CN105861799A (en) * | 2016-05-31 | 2016-08-17 | 攀钢集团攀枝花钢铁研究院有限公司 | Thick vanadium-containing pipeline steel and production method thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101768703A (en) * | 2010-01-26 | 2010-07-07 | 东北大学 | Grade X80 pipe line steel with low yield ratio and manufacturing method thereof |
-
2010
- 2010-09-26 CN CN2010102917515A patent/CN102409148A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101768703A (en) * | 2010-01-26 | 2010-07-07 | 东北大学 | Grade X80 pipe line steel with low yield ratio and manufacturing method thereof |
Non-Patent Citations (2)
| Title |
|---|
| 《材料导报》 20070930 丁文华等 "合金元素和控轧控冷工艺在管线钢研制中的应用" 第67-70、76页 1-4 第21卷, 第9期 * |
| 丁文华等: ""合金元素和控轧控冷工艺在管线钢研制中的应用"", 《材料导报》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103627869A (en) * | 2013-12-06 | 2014-03-12 | 攀钢集团西昌钢钒有限公司 | After-rolling controlled cooling process and preparation method of pipeline steel with low yield ratio |
| CN103627869B (en) * | 2013-12-06 | 2016-03-02 | 攀钢集团西昌钢钒有限公司 | A kind of cooling control after rolling technique of low-yield ratio pipeline steel and preparation method |
| CN105861799A (en) * | 2016-05-31 | 2016-08-17 | 攀钢集团攀枝花钢铁研究院有限公司 | Thick vanadium-containing pipeline steel and production method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103938108B (en) | A kind of 460MPa level low compression ratio high-tenacity steel plate for ocean engineering and production method | |
| CN103602888B (en) | Manufacturing method for low-compression ratio hot-rolled 9Ni steel thick plate | |
| CN100507055C (en) | Yield strength 700MPa grade atmospheric corrosion resistant steel and method for manufacturing same | |
| CN102671938B (en) | High speed production method for controlling banded structure of low carbon steel wire rod | |
| CN102392187B (en) | Cr-containing pipeline steel X70 hot-rolled plate and production method | |
| CN101921955B (en) | Method for manufacturing pipeline steel medium plate with excellent tenacity through normalizing rolling | |
| CN104372247A (en) | 600MPa high-strength antiseismic coil rod twisted steel bar and preparation method thereof | |
| CN103484789B (en) | A kind of high strength prestressed the reinforcement of concrete rod iron of high ductility and working method thereof | |
| CN102021494A (en) | Weather resistant thick steel plate and manufacturing method thereof | |
| CN103952625A (en) | Controlled-rolling and controlled-cooling low-temperature steel bar and preparation method thereof | |
| CN103981461A (en) | X90 pipeline steel wide and thick plate and production method thereof | |
| CN103572025A (en) | Production method of low-cost X52 pipeline steel and pipeline steel | |
| CN102719744A (en) | Steel for low-temperature structures and manufacture method of steel | |
| CN103045939A (en) | Resource-saving Q345 low-alloy series steel plate and production method thereof | |
| CN105057356A (en) | Process for producing screw-thread steel through two-stage rolling control and after-rolling cooling control | |
| CN103774039A (en) | Manufacturing process for steel hot-rolled plate coil for welded gas bottle | |
| CN104109744A (en) | Method for improving pipeline steel drop-weight performance | |
| CN103725960A (en) | Thin high-flexibility pipeline steel plate and production method thereof | |
| CN110923413B (en) | Steel for vanadium microalloyed 600 MPa-grade low-temperature steel bar and production method thereof | |
| CN103422022A (en) | Large-thickness steel plate for low-temperature structure and production method thereof | |
| CN102286692B (en) | Hardened and tempered low-temperature steel and manufacture method thereof | |
| CN102409148A (en) | Controlled cooling method of L450MB pipeline steel | |
| CN103805865A (en) | Economical X70 petroleum and gas pipeline steel and production method thereof | |
| CN105543694A (en) | Preparation method of 7Ni steel plate for liquefied natural gas storage tank | |
| CN102605283A (en) | Low-cost, high-toughness and low-temperature pressure vessel steel and manufacturing method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20120411 |