CN101456032A - Production method of carbon cold-forging steel large coil for 8.8 level high-intensity fasteners - Google Patents
Production method of carbon cold-forging steel large coil for 8.8 level high-intensity fasteners Download PDFInfo
- Publication number
- CN101456032A CN101456032A CNA2009100760723A CN200910076072A CN101456032A CN 101456032 A CN101456032 A CN 101456032A CN A2009100760723 A CNA2009100760723 A CN A2009100760723A CN 200910076072 A CN200910076072 A CN 200910076072A CN 101456032 A CN101456032 A CN 101456032A
- Authority
- CN
- China
- Prior art keywords
- temperature
- rolling
- section
- forging steel
- cooled
- 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 method for producing a carbon element cold forging steel big pony roll for a 8.8 grade high intensity fastening piece, which belongs to the technical field of cold forging steel. Twenty high rigidly short stress line red circle steel bar rolling mills are adopted to roll heated mid-carbon element cold forging steel billet. The billet heated to the temperature of between 1,000 and 1,150 DEG C taken out of a furnace is rough rolled by a 4+4 stander and is medially rolled by a 4 stander. A rolling piece after the mid rolling adopts the first section of water cooling to reduce the surface temperature to be between 770 and 790 DEG C, passes through the restoring section, enters four standers to be precisely rolled at a temperature of between 840 and 860 DEG C; the rolling piece after the precise rolling adopts the second water cooling to reduce the surface temperature to be between 760 and 780 DEG C, passes through the restoring section, enters four standers to be precisely rolled at a temperature of between 830 and 850 DEG C; and the rolling piece after the precision rolling enters the third section water cooling to reduce the temperature of between 830 and 850 DEG C to be curled, the curled piece enters an insulated shield to be cooled by 4,200 to 4,800 seconds at a cooling speed of between 0.08 and 0.30 DEG C per second, and the pony roll is cooled naturally to the room temperature. Phi20mm and Phi38mm pony roll strength Rm can be stably controlled to be less than or equal to 650Mpa, HBW is less than or equal to 170, and Z is more than or equal to 45 percent so that the mid-carbon element cold forging steel pony roll is softened on line and the quality of the pony roll is high.
Description
Technical field
The invention belongs to the cold-forging steel technical field, the production method that particularly provides a kind of 8.8 grade high-strength fasteners to coil greatly with the carbon element cold-forging steel relates in particular to design of low-intensity high-ductility medium carbon steel composition and controlled rolling method.
Background technology
Investment in fastener industry is produced the above 8.8 grades of securing members of M20 and is adopted the big specification of Φ 20～38mm to coil raw material more.The carbon element cold-forging steel of current carbon content commonly used 0.33%～0.45%.This milling method of coiling is that steel billet is heated to 1000～1150 ℃, carry out after steel billet is come out of the stove roughing, in roll, pre-finish rolling, carrying out finish rolling more than 950 ℃ again, usually before and after finish rolling, carry out two sections water-cooleds, control finishing temperature and curling temperature, slowly cool off after the rolling, stocking is organized as ferrite+lamellar pearlite.Because it is big to coil specification, the temperature that rolled piece enters finishing mill is difficult to reach accurate control by one section water-cooled.By between middle milling train and pre-finishing mill, increasing a water-cooled section, be configured to three groups of cooling sections with two sections water-cooled combinations before and after the finishing mill, adopt online temperature closed loop automatic control system to implement the temperature that the classification cooling reduces stocking gradually, accurately the control rolled piece enters the temperature fluctuation of finishing mill at ± 10 ℃, can implement zerolling and go into the stay-warm case slow cooling the whole specifications in Φ 20mm～Φ 38mm scope, to obtain to be applicable to the cold deformation tissue.
Summary of the invention
The production method that the object of the present invention is to provide a kind of 8.8 grade high-strength fasteners to coil greatly with the carbon element cold-forging steel, coil in order to overcome existing rolling large-size, the temperature that rolled piece enters finishing mill is difficult to reach accurate control, the deficiency that technology stability is not high by one section water-cooled.The present invention adopts three sections water-cooled rolling modes to produce Φ 20mm～Φ 38mm and coils the stocking line greatly.Three cooling section correspondences austenitic different conditions in γ → α phase transition process, the bar sectional area is big, take the classification cooling to reduce the temperature of bar gradually, accurately the control rolled piece enters the temperature fluctuation of finishing mill at ± 10 ℃, can implement 850～750 ℃ of zerollings to the whole specifications in Φ 20mm～Φ 38mm scope, the control austenite structure develops; Curl after rolling into the stay-warm case slow cooling, thereby realize control tissue and performance demands, obtain to be applicable to the even interior tissue of cold deformation, satisfy the toughness and tenacity of securing member cold-heading processing request.
The present invention adopts 20 red circle bar mills of high rigidity short-stress path, medium carbon cold-forging steel steel billet to heating is rolled, characteristics are that steel billet is heated to 1000～1150 ℃, the steel billet laggard 4+4 frame roughing of coming out of the stove, roll in 4 frames, in roll the back rolled piece and adopt the 1st section water-cooled that surface temperature is reduced to 780 ± 10 ℃ to enter the pre-finish rolling of 4 frames with 850 ± 10 ℃ through replying section, rolled piece adopts the 2nd section water-cooled that surface temperature is reduced to 770 ± 10 ℃ and enters 4 frame finish rolling through replying section with 840 ± 10 ℃ after the pre-finish rolling, rolled piece enters the 3rd section water-cooled and temperature is reduced to 840 ± 10 ℃ curls after the finish rolling, entering stay-warm case after the rolling, coils and naturally cools to room temperature after 4200～4800 seconds with the slow cooling of 0.08～0.30 ℃/s cooling rate.
Steel billet is heated to 1000～1150 ℃, inside steel billet is organized complete austenitizing, make rolled piece at first the perfect recrystallization district carry out breaking down and in roll, rolled piece is by the 1st section and the 2nd section water-cooled classification cooling subsequently, can be at refine austenite crystal grain to a certain degree, doing tissue for finish rolling prepares, enter the finishing mill temperature at 840 ± 10 ℃ with the control rolled piece, carry out finish to gauge at 850～750 ℃ of low temperature, roll the back with lower cooling velocity slow cooling, form the thin ferrite and the pearlitic structrure of degeneration behind the cooling transformation, reduce the intensity and the hardness of material.Φ 20mm～Φ 38mm coils intensity Rm≤650Mpa, HBW≤170, Z 〉=45%.It is softening to make the medium carbon cold-forging steel coil online acquisition.
The carbon element cold-forging steel composition that the inventive method adopts is (wt%): 0.33%～0.45%C, 0.12%～0.20%Si, 0.65%～0.75%Mn, 0.015%～0.025%Al, P≤0.020%, S≤0.015%, and surplus is Fe.Coiling that the present invention produces is organized as uniformly thin ferrite+nearly globular pearlite.
Compared with prior art, characteristics of the present invention are, it is softening that the medium carbon cold-forging steel that adopts composition design of the present invention and controlled rolling method to produce is coiled online acquisition, its intensity, hardness obviously reduce, the contraction percentage of area improves, acquisition is applicable to the even interior tissue of cold deformation, satisfies the toughness and tenacity of securing member cold-heading processing request.Coil superior in quality.
The specific embodiment
Embodiment 1
The qualified molten steel of steel mill's refining, continuous casting becomes 180 square billets, and chemical composition is C:0.33%, Si:0.19%, Mn:0.68%, Al:0.021%, P:0.012%, S:0.007%, surplus is Fe; Continuous casting billet is heated to 1080 ℃, steel billet is come out of the stove and is rolled in the roughing of laggard 4+4 frame, 4 frames, in roll the back rolled piece and adopt the 1st section water-cooled that surface temperature is reduced to 787 ℃ to enter the pre-finish rolling of 4 frames with 850 ℃ through replying section, rolled piece adopts the 2nd section water-cooled that surface temperature is reduced to 780 ℃ to enter 4 frame finish rolling with 840 ℃ and be rolled into ∮ 20mm through replying section after the pre-finish rolling, rolled piece enters the 3rd section water-cooled and temperature is reduced to 850 ℃ curls after the finish rolling, entering stay-warm case after the rolling, coils and naturally cools to room temperature after 4200 seconds with the slow cooling of 0.080 ℃/s cooling rate.Chemical composition is listed in the table 1, and technological parameter is listed in the table 2, and the stocking mechanical property is listed in the table 3.
Embodiment 2
The qualified molten steel of steel mill's refining, continuous casting becomes 180 square billets, and chemical composition is C:0.35%, Si:0.18%, Mn:0.70%, Al:0.018%, P:0.015%, S:0.006%, surplus is Fe; Continuous casting billet is heated to 1090 ℃, steel billet is come out of the stove and is rolled in the roughing of laggard 4+4 frame, 4 frames, in roll the back rolled piece and adopt the 1st section water-cooled that surface temperature is reduced to 791 ℃ to enter the pre-finish rolling of 4 frames with 850 ℃ through replying section, rolled piece adopts the 2nd section water-cooled that surface temperature is reduced to 775 ℃ to enter 4 frame finish rolling with 840 ℃ and be rolled into ∮ 22mm through replying section after the pre-finish rolling, rolled piece enters the 3rd section water-cooled and temperature is reduced to 845 ℃ curls after the finish rolling, entering stay-warm case after the rolling, coils and naturally cools to room temperature after 4300 seconds with the slow cooling of 0.085 ℃/s cooling rate.Chemical composition is listed in the table 1, and technological parameter is listed in the table 2, and the stocking mechanical property is listed in the table 3.
Embodiment 3
The qualified molten steel of steel mill's refining, continuous casting becomes 200 square billets, and chemical composition is C:0.43%, Si:0.19%, Mn:0.71%, Al:0.023%, P:0.009%, S:0.006%, surplus is Fe; Continuous casting billet is heated to 1070 ℃, steel billet is come out of the stove and is rolled in the roughing of laggard 4+4 frame, 4 frames, in roll the back rolled piece and adopt the 1st section water-cooled that surface temperature is reduced to 780 ℃ to enter the pre-finish rolling of 4 frames with 850 ℃ through replying section, rolled piece adopts the 2nd section water-cooled that surface temperature is reduced to 750 ℃ to enter 4 frame finish rolling with 835 ℃ and be rolled into ∮ 32mm through replying section after the pre-finish rolling, rolled piece enters the 3rd section water-cooled and temperature is reduced to 850 ℃ curls after the finish rolling, entering stay-warm case after the rolling, coils and naturally cools to room temperature after 4800 seconds with the slow cooling of 0.075 ℃/s cooling rate.Chemical composition is listed in the table 1, and technological parameter is listed in the table 2, and the stocking mechanical property is listed in the table 3.
Table 1
| C | Si | Mn | P | S | Alt | Fe | |
| Embodiment 1 | 0.33 | 0.19 | 0.68 | ≤0.012 | ≤0.007 | 0.021 | Surplus |
| Embodiment 2 | 0.35 | 0.18 | 0.70 | ≤0.015 | ≤0.006 | 0.018 | Surplus |
| Embodiment 3 | 0.43 | 0.19 | 0.71 | ≤0.009 | ≤0.006 | 0.023 | Surplus |
Table 2
| Heating-up temperature ℃ | After one section water-cooled ℃ | After two sections water-cooleds ℃ | The temperature of curling ℃ | Cooling rate ℃/s | Slow cooling time S | |
| Embodiment 1 | 1080 | 787 | 780 | 850 | 0.080 | 4200 |
| Embodiment 2 | 1090 | 791 | 775 | 845 | 0.085 | 4300 |
| Embodiment 3 | 1070 | 780 | 750 | 850 | 0.075 | 4800 |
Table 3
| Specification mm | Rm Mpa | Z ％ | HBW | |
| Embodiment 1 | 20 | 580 | 54 | 163 |
| Embodiment 2 | 22 | 595 | 52 | 165 |
| Embodiment 3 | 32 | 610 | 48 | 168 |
Claims (4)
1. the production method coiled greatly with the carbon element cold-forging steel of a grade high-strength fastener adopts 20 red circle bar mills of high rigidity short-stress path, and the medium carbon cold-forging steel steel billet of heating is rolled; It is characterized in that, steel billet is heated to 1000～1150 ℃, the steel billet laggard 4+4 frame roughing of coming out of the stove, roll in 4 frames, in roll the back rolled piece and adopt the 1st section water-cooled that surface temperature is reduced to 780 ± 10 ℃ to enter the pre-finish rolling of 4 frames with 850 ± 10 ℃ through replying section, rolled piece adopts the 2nd section water-cooled that surface temperature is reduced to 770 ± 10 ℃ and enters 4 frame finish rolling through replying section with 840 ± 10 ℃ after the pre-finish rolling, rolled piece enters the 3rd section water-cooled and temperature is reduced to 840 ± 10 ℃ curls after the finish rolling, entering stay-warm case after the rolling, coils and naturally cools to room temperature after 4200～4800 seconds with the cooling of 0.08～0.30 ℃/s cooling rate.
2. production method according to claim 1, it is characterized in that, medium carbon cold-forging steel composition percetage by weight is: 0.33%～0.45%C, 0.12%～0.20%Si, 0.65%～0.75%Mn, 0.015%～0.025%Al, P≤0.020%, S≤0.015%, surplus are Fe.
3. production method according to claim 1 is characterized in that, coiling of production is organized as uniformly thin ferrite+nearly globular pearlite.
4. production method according to claim 1 is characterized in that, Φ 20mm～Φ 38mm coils intensity Rm≤650Mpa, HBW≤170, Z 〉=45%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2009100760723A CN101456032A (en) | 2009-01-06 | 2009-01-06 | Production method of carbon cold-forging steel large coil for 8.8 level high-intensity fasteners |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2009100760723A CN101456032A (en) | 2009-01-06 | 2009-01-06 | Production method of carbon cold-forging steel large coil for 8.8 level high-intensity fasteners |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101456032A true CN101456032A (en) | 2009-06-17 |
Family
ID=40767316
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2009100760723A Pending CN101456032A (en) | 2009-01-06 | 2009-01-06 | Production method of carbon cold-forging steel large coil for 8.8 level high-intensity fasteners |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101456032A (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102560049A (en) * | 2010-12-13 | 2012-07-11 | 天工爱和特钢有限公司 | Steel ingot insulation cover |
| CN102671938A (en) * | 2012-05-08 | 2012-09-19 | 首钢总公司 | High speed production method for controlling banded structure of low carbon steel wire rod |
| CN102716902A (en) * | 2012-06-11 | 2012-10-10 | 内蒙古包钢钢联股份有限公司 | Method for rolling SCM435 steel |
| CN104593673A (en) * | 2014-12-24 | 2015-05-06 | 张家港联峰钢铁研究所有限公司 | Medium carbon non-annealed cold heading steel hot rolled wire rod and production method thereof |
| CN104759469A (en) * | 2015-03-31 | 2015-07-08 | 邢台钢铁有限责任公司 | Production method for non-annealed medium carbon cold heading steel hot-rolled wire rod |
| CN105063309A (en) * | 2015-07-31 | 2015-11-18 | 首钢总公司 | Method for reinforcing low carbon microalloyed steel |
| CN105296865A (en) * | 2014-06-09 | 2016-02-03 | 鞍钢股份有限公司 | Production method for medium-carbon chromium-bearing cold heading steel wire rod |
| CN109136757A (en) * | 2018-09-05 | 2019-01-04 | 包头钢铁（集团）有限责任公司 | The production method of medium carbon cold heading steel wire rod and medium carbon cold heading steel wire rod |
| CN109290367A (en) * | 2018-09-25 | 2019-02-01 | 湖南华菱湘潭钢铁有限公司 | A kind of milling method of corrosion-resistant cold-forging steel |
| CN110129540A (en) * | 2019-06-10 | 2019-08-16 | 南京钢铁股份有限公司 | Improvement bearing steel surface, which is quenched, is tempered the process of line and staff control |
| CN111570537A (en) * | 2020-05-22 | 2020-08-25 | 江苏联峰实业有限公司 | Hot rolling process for improving strength and fracture toughness of steel bar |
| CN114990437A (en) * | 2022-05-25 | 2022-09-02 | 张家港荣盛特钢有限公司 | Cold heading steel wire rod and production method thereof |
-
2009
- 2009-01-06 CN CNA2009100760723A patent/CN101456032A/en active Pending
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102560049A (en) * | 2010-12-13 | 2012-07-11 | 天工爱和特钢有限公司 | Steel ingot insulation cover |
| CN102671938A (en) * | 2012-05-08 | 2012-09-19 | 首钢总公司 | High speed production method for controlling banded structure of low carbon steel wire rod |
| CN102671938B (en) * | 2012-05-08 | 2014-04-30 | 首钢总公司 | High speed production method for controlling banded structure of low carbon steel wire rod |
| CN102716902A (en) * | 2012-06-11 | 2012-10-10 | 内蒙古包钢钢联股份有限公司 | Method for rolling SCM435 steel |
| CN105296865A (en) * | 2014-06-09 | 2016-02-03 | 鞍钢股份有限公司 | Production method for medium-carbon chromium-bearing cold heading steel wire rod |
| CN104593673A (en) * | 2014-12-24 | 2015-05-06 | 张家港联峰钢铁研究所有限公司 | Medium carbon non-annealed cold heading steel hot rolled wire rod and production method thereof |
| CN104759469A (en) * | 2015-03-31 | 2015-07-08 | 邢台钢铁有限责任公司 | Production method for non-annealed medium carbon cold heading steel hot-rolled wire rod |
| CN105063309A (en) * | 2015-07-31 | 2015-11-18 | 首钢总公司 | Method for reinforcing low carbon microalloyed steel |
| CN109136757A (en) * | 2018-09-05 | 2019-01-04 | 包头钢铁（集团）有限责任公司 | The production method of medium carbon cold heading steel wire rod and medium carbon cold heading steel wire rod |
| CN109136757B (en) * | 2018-09-05 | 2020-10-27 | 包头钢铁（集团）有限责任公司 | Production method of medium-carbon cold heading steel wire and medium-carbon cold heading steel wire |
| CN109290367A (en) * | 2018-09-25 | 2019-02-01 | 湖南华菱湘潭钢铁有限公司 | A kind of milling method of corrosion-resistant cold-forging steel |
| CN110129540A (en) * | 2019-06-10 | 2019-08-16 | 南京钢铁股份有限公司 | Improvement bearing steel surface, which is quenched, is tempered the process of line and staff control |
| CN111570537A (en) * | 2020-05-22 | 2020-08-25 | 江苏联峰实业有限公司 | Hot rolling process for improving strength and fracture toughness of steel bar |
| CN111570537B (en) * | 2020-05-22 | 2022-02-11 | 江苏联峰实业有限公司 | Hot rolling process for improving strength and fracture toughness of steel bar |
| CN114990437A (en) * | 2022-05-25 | 2022-09-02 | 张家港荣盛特钢有限公司 | Cold heading steel wire rod and production method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101456032A (en) | Production method of carbon cold-forging steel large coil for 8.8 level high-intensity fasteners | |
| CN101045238A (en) | Online softening rolling method for medium carbon alloy cold forging steel | |
| CN113245365B (en) | Rolling production method for improving toughness of steel on line | |
| CN106566989B (en) | One kind broad hot strip of tool containing vanadium and its production method | |
| CN103966411B (en) | A kind of manufacture method of medium carbon cold heading steel Bar Wire Product | |
| CN110777244B (en) | Medium-carbon high-sulfur free-cutting steel and preparation process thereof | |
| CN107419194A (en) | A kind of processing method of super austenitic stainless steel coiled sheet | |
| CN102418033B (en) | Heat-treatment-free high-strength cold heading steel and production method for hot rolled bar of heat-treatment-free high-strength cold heading steel | |
| CN102978362B (en) | Thermal control and cold control process of ultralow-carbon fiber steel | |
| CN102417959A (en) | Method for producing annealing-free hot rolling S50C plate and strip | |
| CN102808131A (en) | Method for manufacturing high-quality high-strength cold forging steel with uniform texture performance | |
| CN102517500A (en) | Rolling process for producing 35CrMo alloy cold forging steel through adopting small billets | |
| CN105401090B (en) | A kind of precision stamping automotive seat regulation tooth plate cold-rolled steel sheet and its manufacture method | |
| CN101906519A (en) | Manufacture method of low yield ratio surface layer ultra fine grain low-carbon steel thick plate | |
| CN104759469A (en) | Production method for non-annealed medium carbon cold heading steel hot-rolled wire rod | |
| CN101633976A (en) | Direct quenching technology suitable for steel plates with different thicknesses and high durability | |
| CN104593679A (en) | Non-annealed cold forging steel wire rod for 10.9-grade high-strength screw and production process thereof | |
| CN110184533A (en) | A kind of low silicon universal-joint Rzeppa steel and manufacturing method | |
| PL433607A1 (en) | Method of producing steel wire rod with a round cross-section and steel wire rod with a round cross-section | |
| CN101829679B (en) | Production method for producing shock toughness of pipe coupling material of hot rolled oil well | |
| CN106834640A (en) | A kind of manufacture method of low-alloy structural steel hot rolled steel plate | |
| CN104745787B (en) | Production method of tool steel capable of being directly cold rolled | |
| CN104646422B (en) | Intermediate roll of multi-roll mill and manufacturing method thereof | |
| CN104593665A (en) | Method for manufacturing thick hot-rolled dual-phase steel based on CSP (Compact Strip Production) process | |
| CN109136757B (en) | Production method of medium-carbon cold heading steel wire and medium-carbon cold heading steel wire |
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 |
Open date: 20090617 |