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CN104907353A - Production method of high-chromium ferrite stainless-steel seamless steel pipe blank - Google Patents

Production method of high-chromium ferrite stainless-steel seamless steel pipe blank Download PDF

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Publication number
CN104907353A
CN104907353A CN201510334811.XA CN201510334811A CN104907353A CN 104907353 A CN104907353 A CN 104907353A CN 201510334811 A CN201510334811 A CN 201510334811A CN 104907353 A CN104907353 A CN 104907353A
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heating
section
production method
steel pipe
ferrite stainless
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CN104907353B (en
Inventor
鄢勇
尹人洁
王婀娜
童宗圣
张涛
江健
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Pangang Group Chengdu Steel and Vanadium Co Ltd
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Pangang Group Chengdu Steel and Vanadium Co Ltd
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21CMANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C37/00Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
    • B21C37/06Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Forging (AREA)

Abstract

The invention belongs to the technical field of metallurgy and particularly relates to a production method of a high-chromium ferrite stainless-steel 2Cr25N seamless steel pipe blank. The process flow of the production method comprises the following steps: scalping a round blank, heating a forging blank and perforating, wherein a perforating device is used for perforating the round blank to form a rough pipe blank; in the perforating procedure, the total-diameter reduction rate is 8-12%, the top-front reduction rate is less than or equal to 4%, and the ellipticity is 1.06-1.14. The production method has the characteristics of short production period, low preparation cost and the like; and the yield of steel pipes prepared by the blank is high.

Description

The production method of high chromium content ferrite stainless steel seamless steel pipe blank
Technical field
The invention belongs to metallurgical technology field, be specifically related to a kind of production method of high chromium content ferrite stainless steel 2Cr25N seamless steel pipe blank.
Background technology
High chromium content ferrite stainless steel 2Cr25N, high containing Cr amount, non-oxidizability is better than the ferritic stainless steel of Cr13 and Cr18 type, is particularly suitable for using under the condition of temperature fierceness fluctuation.The various heat-resistant components worked under can being produced on more than 950 DEG C loading condictions.In traditional production technology, ferrite stainless steel pipe mainly adopts extruded mode to produce, and concrete technology flow process is: main employing " strip off the skin forging stock → bore hole → eddy-current heating → reaming → eddy-current heating → extruding "; " strip off the skin forging stock → bore hole → eddy-current heating → reaming " is wherein its blank preparatory process, and this production process is relatively long, simultaneously bore hole, reaming procedure, except its operation processing charges, has larger lumber recovery loss simultaneously.
Summary of the invention
For above-mentioned defect, the invention provides a kind of production method of high chromium 2Cr25N ferritic stainless seamless steel tube blank newly, the features such as method of the present invention has with short production cycle, and preparation cost is low.
Technical scheme of the present invention:
The invention provides a kind of production method of high chromium content ferrite stainless steel seamless steel pipe blank, its technological process comprises: the round base that strips off the skin → heating forging stock → perforation, wherein:
Use punching machine to carry out perforation to circle base and form hollow billet blank; In perforation process, overall diameter reduction ratio is 8 ~ 12%, and top front reduction ratio is≤4%, and ovality is 1.06 ~ 1.14.
Further, rotary heating furnace, roller hearth type heating furnace or eddy-current heating is adopted in described heating forging stock operation.
In heating forging stock operation, adopt rotary heating furnace heating, rotary heating furnace is followed successively by heat-recovery section, preheating section, bringing-up section, soaking zone from charging end to discharge end; Wherein, heat-recovery section temperature (i.e. forging stock material charging temperature) is lower than 800 DEG C, and preheating section temperature controls at 1000 ~ 1030 DEG C, bringing-up section temperature≤1250 DEG C, and soaking zone temperature controls at 1230 DEG C ~ 1260 DEG C.General, at annular furnace charging aperture, place arranges heat-recovery section, and heat-recovery section utilizes and is arranged on the heat energy that preheating section thereafter, bringing-up section, the waste heat flue gas that produces of heat supply burner combustion of soaking zone and high temperature section bring and carries out preheating to the pipe through heat-recovery section.
Preferred, heating forging stock operation adopts rotary heating furnace heating, and rotary heating furnace is followed successively by heat-recovery section, preheating section, bringing-up section, soaking zone from charging end to discharge end; Bringing-up section is divided into heating 1 section, heating 2 sections, wherein, forging stock material is in 5 ~ 7 hours heat times of heat-recovery section, preheating section, heating 1 section (i.e. low-temperature zone), 1.5 ~ 2 hours are less than in the heat time of heating 2 sections, soaking zone (i.e. high temperature section), thus making overall heating-up temperature even, forging stock intensity is suitable for the solid blank formed of boring a hole.
Further, perforation employing two roller oblique milling bevel-type punch, cartridge type punch or cone mill
Preferably, after perforation, rolling is front to blank endoporus nitrogen blowing and sandblasting, to eliminate inner surface oxide skin and anti-oxidation.
Concrete, the specification of described high chromium content ferrite stainless steel seamless steel pipe blank is Ф 225 × 16.2mm, and its technological process comprises: the round base that strips off the skin → heating forging stock → perforation, wherein:
In perforation process, adopt two-high cone shape piercing machine to bore a hole, penetrating parameter is: feed angle 8.5 °, 14 °, roll off angle, roll spacing 179.55mm, lead 202mm, the top amount of stretching 150mm, godet speed 1.5m/s, mill speed 0.4 ~ 1.0 (being preferably 0.55m/s) m/s.
In heating forging stock operation, adopt rotary heating furnace mode of heating, rotary heating furnace is followed successively by heat-recovery section, preheating section, bringing-up section, soaking zone from charging end to discharge end; Wherein, forging stock material charging temperature (i.e. heat-recovery section) is lower than 800 DEG C; Preheating section temperature control 1000 ~ 1030 DEG C, bringing-up section temperature≤1250 DEG C, soaking zone temperature control to be 1230 DEG C ~ 1260 DEG C, ensures that 2Cr25N blank heating is even.
Beneficial effect of the present invention:
The present invention is by suitable tool and mould and parameters adjusting, and technological innovation in production procedure, adopts the mode of " forging stock that strips off the skin → annular furnace heating → punch perforation " to carry out the preparation of its blank pipe, reach raising lumber recovery, reduce the object of blank cost.
Detailed description of the invention
The invention provides a kind of production method of high chromium content ferrite stainless steel seamless steel pipe blank, its technological process comprises: the round base that strips off the skin → heating forging stock → perforation, wherein:
Use punching machine to carry out perforation to circle base and form hollow billet blank; In perforation process, overall diameter reduction ratio is 8 ~ 12%, top front reduction ratio≤4%, and ovality is 1.06 ~ 1.14; Wherein, minimum diameter/original blank diameter × 100% of blank in overall diameter reduction ratio=deformation process; Top front reduction ratio=blank just contacts blank diameter/original blank diameter × 100% during top; Ovality=lead/roll spacing; Described high chromium content ferrite stainless steel is 2Cr25N steel.
The round base that strips off the skin refers to circular blank outer surface being carried out to the process such as machined or reconditioning.
Perforation principle utilizes pipe center metal to split and not disconnected rarefaction, and top is placed in puffs bores a hole, thus the best resultant effect of the mechanics of acquisition perforation procedure, kinematics and quality of hollow billet.The adjustment of piercing process parameter from the feature of austenitic stainless steel, will reach two objects: one is create good deformation condition, and ensure carrying out smoothly of perforation procedure, two is prevent surfaces externally and internally defect.
Top front reduction ratio: when namely blank just contacts top, blank diameter and original blank diameter ratio.By top front reduction ratio, people's custom represents that pipe forms the degree of danger of vestibule, and by this parameter as one of important evidence determining punch hole type design and the adjustment of position, top; Top front reduction ratio is too small, then the secondary that cannot realize boring a hole is nipped; Excessive, then easily form vestibule, cause infolding; The strength degree of steel is different with plasticity, and its critical compresibility is also different, and the factor simultaneously had an impact to it comprises macrostructure, mirco structure and heating quality etc.; But because blank is less, and high temperature hot deformation resistance is large, during pipe distortion, center rubbing is violent, and top front reduction ratio not easily arranges excessive.
Ovality: ovality is guidance disc distance and the ratio of roll distance, and ovality affects quality of hollow billet, bite condition, axial slip, punching rate, expanding amount, rolls card and hollow billet size Control etc.; Particularly more obvious on quality of hollow billet impact, ovality is larger, and metal transversely deforming is increased, and axial deformation reduces, and metal transversely deforming increase can cause the tension of pipe center to increase, and impels the formation of pipe center bore; The pipe blank rotary that too small ovality can cause roll to be formed and advance be short of power to offset its frictional force with top resistance time, then can cause stall, roll card; Visible, the setting of ovality should be taken into account the multiple situations such as the quality of blank, drag, unit capacity and production specification.Stainless steel spreads larger than carbon steel, and therefore ovality Selection radio carbon steel (being generally 1.08) is slightly large.
Roll rotational speed: the speed of rolls of control punch machine is very important to suppression hollow billet heat, and punching rate is faster, and the temperature of hollow billet, especially internal surface temperature are higher, causes the increase of defect in inner surface and the wearing and tearing of rolling tool; General speed just bored a hole by stainless steel tube should not be too fast.
Further, rotary heating furnace, roller hearth type heating furnace or eddy-current heating is adopted in described heating forging stock operation.
In heating forging stock operation, adopt rotary heating furnace heating, rotary heating furnace is followed successively by heat-recovery section, preheating section, bringing-up section, soaking zone from charging end to discharge end; Wherein, heat-recovery section temperature (i.e. forging stock material charging temperature) is lower than 800 DEG C, and preheating section temperature controls at 1000 ~ 1030 DEG C, bringing-up section temperature≤1250 DEG C, and soaking zone temperature controls at 1230 DEG C ~ 1260 DEG C.General, at annular furnace charging aperture, place arranges heat-recovery section, and heat-recovery section utilizes and is arranged on the heat energy that preheating section thereafter, bringing-up section, the waste heat flue gas that produces of heat supply burner combustion of soaking zone and high temperature section bring and carries out preheating to the pipe through heat-recovery section.
Preferred, heating forging stock operation adopts rotary heating furnace heating, and rotary heating furnace is followed successively by heat-recovery section, preheating section, bringing-up section, soaking zone from charging end to discharge end; Bringing-up section is divided into heating 1 section, heating 2 sections, wherein, forging stock material is in 5 ~ 7 hours heat times of heat-recovery section, preheating section, heating 1 section (i.e. low-temperature zone), 1.5 ~ 2 hours are less than in the heat time of heating 2 sections, soaking zone (i.e. high temperature section), thus making overall heating-up temperature even, forging stock intensity is suitable for the solid blank formed of boring a hole.In the present invention, because the pyroconductivity of stainless steel when low temperature is only 1/3 ~ 1/2 of ordinary carbon steel, be significantly less than the pyroconductivity of conventional carbon steel, if heat too fast, easily cause blank bulk temperature uneven, even ftracture time serious; When the high temperature of about 1000 DEG C, the two pyroconductivity is roughly the same, and during the high temperature of high Cr stainless steel more than 1100 DEG C, easily produces Cr segregation, affect high temperature plastic, therefore should not be long in the high temperature section time.
Below in conjunction with embodiment, the specific embodiment of the present invention is further described, does not therefore limit the present invention among described scope of embodiments.
Adopt 4 Φ 200mm, 2Cr25N forging stocks, when heating-up temperature is 1230 DEG C ~ 1260 DEG C control, at Pangang Group Chengdu Steel & Vanadium Co., Ltd. 159 unit, carry out production 89 × 5mm specification seamless steel pipe by the following method; The concrete production technology of its blank is as follows:
Heating requirements: adopt rotary heating furnace mode of heating in heating forging stock operation, rotary heating furnace is followed successively by heat-recovery section, preheating section, bringing-up section, soaking zone from charging end to discharge end; Wherein, forging stock material charging temperature (i.e. heat-recovery section) is lower than 800 DEG C; Preheating section temperature control 1000 ~ 1030 DEG C, bringing-up section temperature≤1250 DEG C, soaking zone temperature control to be 1230 DEG C ~ 1260 DEG C, ensures that all even each section of temperature of 2Cr25N blank heating press the control of 2Cr25N temperature requirement.After steel pipe goes out annular furnace, bore a hole at two-high cone shape piercing machine, penetrating parameter is as shown in table 1:
Table 1
By following formula measuring and calculating overall diameter reduction ratio, top front reduction ratio and ovality under this technological parameter:
Minimum diameter/original blank diameter × 100% of blank in overall diameter reduction ratio=deformation process;
Top front reduction ratio=blank just contacts blank diameter/original blank diameter × 100% during top;
Ovality=lead/roll spacing; Calculating overall diameter reduction ratio is 10%, and top front reduction ratio is 1.7%, and ovality is 1.122, and gained hollow billet specification is 225 × 16.2mm, and length is 2 ~ 8m.Utilizing the inventive method to produce steel pipe (i.e. hollow billet) single Zhi Changdu is 2 ~ 8m, and main lumber recovery loss is scaling loss, and lumber recovery can reach more than 98%.

Claims (7)

1. the production method of high chromium content ferrite stainless steel seamless steel pipe blank, is characterized in that, its technological process comprises: the round base that strips off the skin → heating forging stock → perforation, wherein:
Use punching machine to carry out perforation to circle base and form hollow billet blank; In perforation process, overall diameter reduction ratio is 8 ~ 12%, and top front reduction ratio is≤4%, and ovality is 1.06 ~ 1.14.
2. the production method of high chromium content ferrite stainless steel seamless steel pipe blank according to claim 1 and 2, is characterized in that, adopts rotary heating furnace, roller hearth type heating furnace or eddy-current heating in described heating forging stock operation.
3. the production method of high chromium content ferrite stainless steel seamless steel pipe blank according to claim 2, it is characterized in that, in heating forging stock operation, adopt rotary heating furnace heating, rotary heating furnace is followed successively by heat-recovery section, preheating section, bringing-up section, soaking zone from charging end to discharge end; Wherein, heat-recovery section temperature is lower than 800 DEG C, and preheating section temperature controls at 1000 ~ 1030 DEG C, bringing-up section temperature≤1250 DEG C, and soaking zone temperature controls at 1230 DEG C ~ 1260 DEG C.
4. the production method of high chromium content ferrite stainless steel seamless steel pipe blank according to claim 3, it is characterized in that, heating forging stock operation adopts rotary heating furnace heating, bringing-up section is divided into heating 1 section, heating 2 sections, wherein, forging stock material, in 5 ~ 7 hours heat times of heat-recovery section, preheating section, heating 1 section, is less than 1.5 ~ 2 hours in the heat time of heating 2 sections, soaking zone.
5. the production method of the high chromium content ferrite stainless steel seamless steel pipe blank according to any one of Claims 1 to 4, is characterized in that, perforation employing two roller oblique milling bevel-type punch, cartridge type punch or cone mill.
6. the production method of the high chromium content ferrite stainless steel seamless steel pipe blank according to any one of Claims 1 to 5, is characterized in that, after perforation, rolling is front to blank endoporus nitrogen blowing and sandblasting, to eliminate inner surface oxide skin and anti-oxidation.
7. the production method of the high chromium content ferrite stainless steel seamless steel pipe blank according to any one of claim 1 ~ 6, is characterized in that, the specification of described high chromium content ferrite stainless steel seamless steel pipe blank is Ф 225 × 16.2mm, in its technological process:
In perforation process, adopt two-high cone shape piercing machine to bore a hole, penetrating parameter is: feed angle 8.5 °, 14 °, roll off angle, roll spacing 179.55mm, lead 202mm, the top amount of stretching 150mm, godet speed 1.5m/s, mill speed 0.4 ~ 1.0m/s.
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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106238465A (en) * 2016-08-11 2016-12-21 攀钢集团成都钢钒有限公司 A kind of preparation method of PH stainless steel seamless steel pipe
CN107774715A (en) * 2016-08-30 2018-03-09 林州凤宝管业有限公司 The double chi production technology of the pipes of vehicle bridge pipe Φ 220
CN112570487A (en) * 2020-11-24 2021-03-30 江苏联峰能源装备有限公司 Molding process for producing X80 pipeline steel seamless steel tube by adopting phi 800 mm large round billet
CN112894276A (en) * 2021-01-18 2021-06-04 中国兵器工业第五九研究所 Deep blind hole cylindrical component and manufacturing method thereof
CN113441551A (en) * 2021-06-30 2021-09-28 北京科技大学 Thick-walled seamless steel pipe and preparation method thereof
CN113600637A (en) * 2021-06-30 2021-11-05 北京科技大学 Seamless steel pipe and preparation method thereof
CN113976628A (en) * 2021-11-08 2022-01-28 中冶东方工程技术有限公司 Production process and device of stainless steel seamless steel pipe

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CN101327492A (en) * 2008-07-30 2008-12-24 郝建庚 Process and system for manufacturing hot-rolled seamless tube
CN101337236A (en) * 2007-07-06 2009-01-07 中冶东方工程技术有限公司 Rolling mill technique of three-roller full-floating core rod tandem rolling tube
CN103736734A (en) * 2013-12-30 2014-04-23 江苏常宝钢管股份有限公司 Process of preparing high-chromium alloy supper 13-Cr seamless steel tubes through CPE (cross-roll piercing and elongation) hot rolling mill

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CN101020192A (en) * 2007-03-21 2007-08-22 中冶东方工程技术有限公司 Hot rolling process of seamless steel pipe
CN101337236A (en) * 2007-07-06 2009-01-07 中冶东方工程技术有限公司 Rolling mill technique of three-roller full-floating core rod tandem rolling tube
CN101327492A (en) * 2008-07-30 2008-12-24 郝建庚 Process and system for manufacturing hot-rolled seamless tube
CN103736734A (en) * 2013-12-30 2014-04-23 江苏常宝钢管股份有限公司 Process of preparing high-chromium alloy supper 13-Cr seamless steel tubes through CPE (cross-roll piercing and elongation) hot rolling mill

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106238465A (en) * 2016-08-11 2016-12-21 攀钢集团成都钢钒有限公司 A kind of preparation method of PH stainless steel seamless steel pipe
CN106238465B (en) * 2016-08-11 2019-02-05 攀钢集团成都钢钒有限公司 A kind of preparation method of PH stainless steel seamless steel pipe
CN107774715A (en) * 2016-08-30 2018-03-09 林州凤宝管业有限公司 The double chi production technology of the pipes of vehicle bridge pipe Φ 220
CN107774715B (en) * 2016-08-30 2019-11-05 林州凤宝管业有限公司 The double ruler production technology of 220 pipe of vehicle bridge pipe Φ
CN112570487A (en) * 2020-11-24 2021-03-30 江苏联峰能源装备有限公司 Molding process for producing X80 pipeline steel seamless steel tube by adopting phi 800 mm large round billet
CN112894276B (en) * 2021-01-18 2022-04-08 中国兵器工业第五九研究所 Deep blind hole cylindrical component and manufacturing method thereof
CN112894276A (en) * 2021-01-18 2021-06-04 中国兵器工业第五九研究所 Deep blind hole cylindrical component and manufacturing method thereof
CN113441551A (en) * 2021-06-30 2021-09-28 北京科技大学 Thick-walled seamless steel pipe and preparation method thereof
CN113600637A (en) * 2021-06-30 2021-11-05 北京科技大学 Seamless steel pipe and preparation method thereof
CN113600637B (en) * 2021-06-30 2022-04-15 北京科技大学 Seamless steel pipe and preparation method thereof
CN113441551B (en) * 2021-06-30 2022-07-01 北京科技大学 Thick-walled seamless steel pipe and preparation method thereof
CN113976628A (en) * 2021-11-08 2022-01-28 中冶东方工程技术有限公司 Production process and device of stainless steel seamless steel pipe
CN113976628B (en) * 2021-11-08 2024-05-28 中冶东方工程技术有限公司 Production process and device of stainless steel seamless steel tube

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