CN104862593B - The preparation method of ferritic stainless seamless steel tube - Google Patents
The preparation method of ferritic stainless seamless steel tube Download PDFInfo
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- CN104862593B CN104862593B CN201510205879.8A CN201510205879A CN104862593B CN 104862593 B CN104862593 B CN 104862593B CN 201510205879 A CN201510205879 A CN 201510205879A CN 104862593 B CN104862593 B CN 104862593B
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Abstract
The present invention relates to the preparation method of a kind of ferritic stainless seamless steel tube, its preparation method comprises the following steps: (a) hot-puncturing process；B () pickling & for the first time checks；C () lubricates；(d) cold-drawn/cold rolling；(e) pickling for the second time；(f) heat treatment；G () pickling & for the third time checks.By promoting the percentage by weight of Si, Al in its component so that stainless non-oxidizability is greatly improved, it is provided that have high yield strength and low plasticity, and thermal conductivity is 1.5 times of austenitic stainless steel；The each step of preparation method of this ferritic stainless seamless steel tube is all linked with one another, and operates relatively simple, makes ferritic stainless seamless steel tube have relatively low cost.
Description
Technical field
The invention belongs to field of iron and steel, relate to a kind of seamless steel pipe, be specifically related to a kind of ferritic stainless seamless steel tube and
Its preparation method.
Background technology
Steel plant's blast furnace is equipment Ore being refined into the pig iron.Ironmaking processes there is a large amount of high-temp waste gas discharge, make full use of height
The big energy contained in temperature waste gas is the important step that ironmaking reduces cost.Therefore, a lot of steel plant are at Waste gas outlet
Installing heat exchanger, the wind of steel-making is preheated by the heat then obtained by heat exchanger exchange.The temperature of Waste gas outlet is high
Reach 800～950 DEG C, and containing substantial amounts of sulfur dioxide in waste gas；If use common No. 20 steel pipe, although heat transfer effect
Preferably, but it will soon damage under the influence of high temperature and etchant gas；If converted to the erosion-resisting austenite of high temperature resistance is not
Rust steel pipe, then the heat exchanger of making is expensive, and heat transfer effect substantially reduces.Therefore, in the urgent need to preparation one not
Rust steel seamless steel tube is while having preferable heat transfer effect, relatively low cost, moreover it is possible to antioxidation, anticorrosive.
Summary of the invention
The invention aims to overcome the deficiencies in the prior art to provide a kind of ferritic stainless seamless steel tube.
For reaching above-mentioned purpose, the technical solution adopted in the present invention is: a kind of ferritic stainless seamless steel tube, described ferrum element
The element weight percent of body stainless-steel seamless pipe is as follows, C :≤0.03%, Si:0.7～1.1%, Mn :≤1%, P :≤0.03%；
S :≤0.02%, Cr:17～19%, Ti:0.2～0.4%, N :≤0.025%, Cu :≤0.25%, Al:0.8～1.2%, surplus
For Fe.
Optimally, the element weight percent of described ferritic stainless seamless steel tube is as follows, C:0.03%, Si:0.7%,
Mn:1%, P:0.03%；S:0.02%, Cr:17%, Ti:0.2%, N:0.025%, Cu:0.25%, Al:0.8%,
Surplus is Fe.
Optimally, the element weight percent of described ferritic stainless seamless steel tube is as follows, C:0.03%, Si:1.1%,
Mn:1%, P:0.03%；S:0.02%, Cr:19%, Ti:0.4%, N:0.025%, Cu:0.25%, Al:1.2%,
Surplus is Fe.
Optimally, the element weight percent of described ferritic stainless seamless steel tube is as follows, C:0.03%, Si:1.0%,
Mn:1%, P:0.03%；S:0.02%, Cr:18%, Ti:0.3%, N:0.025%, Cu:0.25%, Al:1.0%,
Surplus is Fe.
A further object of the present invention is to provide the preparation method of a kind of above-mentioned ferritic stainless seamless steel tube, and it includes following step
Rapid:
A () hot-puncturing process: pipe is placed in 1150～1160 DEG C and is incubated 30～60 minutes, controlling the front compression ratio in top is 4.5～5.0%
Perforation, natural cooling subsequently；
B () pickling & for the first time checks: the steel pipe Fluohydric acid. and the nitric acid mixed solution that prepare in step (a) are carried out pickling,
Use endoscope, visual mode that its surfaces externally and internally carries out Crack Detection respectively again, confirm that the surfaces externally and internally of steel pipe has free from flaw；
Described pickling time is 30～60min, and the mass concentration 2～3% of described Fluohydric acid., the mass concentration of described nitric acid is respectively 4～5%；
C () lubricates: do not have crannied steel pipe surfaces externally and internally brushing lubricant after detection in step (b), be placed in 200～250
DEG C dry；Described lubricant comprises industry fat and lime water；
(d) cold-drawn/cold rolling: the steel pipe obtained in step (c) is carried out cold rolling in cold mill complex, cold working in cold-rolled process
Deformation amount controlling is within 60%；
(e) pickling for the second time: by the steel pipe mass concentration obtained in step (d) be 4～5% salpeter solution in carry out acid
Wash；
(f) heat treatment: be placed in 780～820 DEG C of insulations 45～75 minutes, natural cooling subsequently by obtaining steel pipe in step (e)；
G () pickling & for the third time checks: the steel pipe obtained in step (f) described Fluohydric acid. and nitric acid mixed solution are carried out
Pickling, pickling time is 40min；Put in storage after carrying out Non-Destructive Testing after washing and drying again.
Optimally, described lubricant comprises the component of following parts by weight: 1～3 part of No. 3 industrial fat and 8～15 parts of lime water.
Optimally, in described step (a), first stamp internal point at pipe end face, it is simple to centering during perforation, put subsequently
In heating furnace, it is heated to 800 DEG C with the speed of 8～10 DEG C/min, then is heated to 1150～1160 DEG C with 20～30 DEG C/min speed.
Due to technique scheme use, the present invention compared with prior art have the advantage that ferritic stainless steel of the present invention without
Seam steel pipe, by promoting the percentage by weight of Si, Al in its component so that stainless non-oxidizability is greatly improved,
Thering is provided and have high yield strength and low plasticity, thermal conductivity is 1.5 times of austenitic stainless steel；This ferritic stainless steel is seamless
The each step of preparation method of steel pipe is all linked with one another, and operates relatively simple, makes ferritic stainless seamless steel tube have relatively low one-tenth
This.
Detailed description of the invention
Ferritic stainless seamless steel tube of the present invention, its element weight percent is as follows, C :≤0.03%, Si:0.7～1.1%,
Mn :≤1%, P :≤0.03%；S :≤0.02%, Cr:17～19%, Ti:0.2～0.4%, N :≤0.025%, Cu :≤0.25%,
Al:0.8～1.2%, surplus is Fe.By promoting the percentage by weight of Si, Al in its component so that stainless anti-
Oxidisability is greatly improved, it is provided that have high yield strength and low plasticity, and thermal conductivity is 1.5 times of austenitic stainless steel, special
It is not applicable on steel plant's blast furnace heat exchanger.Its element weight percent is preferably C:0.03%, Si:0.7%, Mn:1%,
P:0.03%；S:0.02%, Cr:17%, Ti:0.2%, N:0.025%, Cu:0.25%, Al:0.8%, surplus is
Fe；Or preferably C:0.03%, Si:1.1%, Mn:1%, P:0.03%；S:0.02%, Cr:19%, Ti:0.4%,
N:0.025%, Cu:0.25%, Al:1.2%, surplus is Fe, and this preferred ferritic stainless seamless steel tube performance is best,
It is because the Ti element with high level, it is possible to promote toughness and the intensity of whole material；Or preferably C:0.03%,
Si:1.0%, Mn:1%, P:0.03%；S:0.02%, Cr:18%, Ti:0.3%, N:0.025%, Cu:0.25%,
Al:1.0%, surplus is Fe.
The preparation method of above-mentioned ferritic stainless seamless steel tube, it comprises the following steps: (a) hot-puncturing process: be placed in by pipe
1150～1160 DEG C be incubated 30～60 minutes, control top before compression ratio be 4.5～5.0% perforation, natural cooling subsequently；(b) first
Secondary pickling is checked: the steel pipe Fluohydric acid. and the nitric acid mixed solution that prepare in step (a) carried out pickling, then use endoscope,
Visual mode carries out Crack Detection respectively to its surfaces externally and internally, confirms that the surfaces externally and internally of steel pipe has free from flaw；Described pickling time
Being 30～60min, the mass concentration 2～3% of described Fluohydric acid., the mass concentration of described nitric acid is respectively 4～7%；C () lubricates:
In step (b), do not have crannied steel pipe surfaces externally and internally brushing lubricant after detection, be placed in 200～250 DEG C of drying, described lubrication
Agent comprises industry fat and lime water, uses industry fat and lime water on the one hand can play the matrix of steel pipe and mould in lubricant
Buffer action and lubrication, be on the other hand also beneficial to the removing of subsequent step；(d) cold-drawn/cold rolling: by step (c)
The steel pipe obtained carries out cold rolling in cold mill complex, and in cold-rolled process, cold deformation controls within 60%；E () for the second time
Pickling: by the steel pipe mass concentration obtained in step (d) be 4～5% salpeter solution in carry out pickling, be used for removing lubrication
Agent；(f) heat treatment: be placed in 780～820 DEG C of insulations 45～75 minutes, natural cooling subsequently by obtaining steel pipe in step (e)；
G () pickling & for the third time checks: the steel pipe obtained in step (f) described Fluohydric acid. and nitric acid mixed solution are carried out pickling,
Pickling time is 30～60min；Put in storage after carrying out Non-Destructive Testing after washing and drying again.Lubricant preferably comprises following parts by weight
Component: 1～3 part of No. 3 industrial fat and 8～15 parts of saturated limewaters, the mixing of both materials can work in coordination with reduction friction；
And the effect of No. 3 industrial fat of removing is best after drying, reduces the time of follow-up second time pickling, only needs 30～60 minutes.
Step (a) is preferably, first stamps internal point at pipe end face, it is simple to centering during perforation, be conducive to the quality of perforation；Subsequently
It is placed in heating furnace and is heated to 800 DEG C with the speed of 8～10 DEG C/min, then be heated to 20～30 DEG C/min speed
1150～1160 DEG C, so it is able to ensure that pipe has uniform temperature before boring a hole in being incubated 30～60 minutes.
Below the preferred embodiment of the invention is described in detail:
Embodiment 1
A kind of ferritic stainless seamless steel tube of the present embodiment offer, its element weight percent following C:0.03%, Si:0.7%,
Mn:1%, P:0.03%；S:0.02%, Cr:17%, Ti:0.2%, N:0.025%, Cu:0.25%, Al:0.8%,
Surplus is Fe；Its preparation method comprises the following steps:
(a) hot-puncturing process: pipe is placed in 1150 DEG C and is incubated 60 minutes, controlling the front compression ratio in top is 4.5% perforation, with
Rear natural cooling；
B () pickling & for the first time checks: the steel pipe Fluohydric acid. and the nitric acid mixed solution that prepare in step (a) are carried out pickling,
Use endoscope, visual mode that its surfaces externally and internally carries out Crack Detection respectively again, confirm that the surfaces externally and internally of steel pipe has free from flaw；
Described pickling time is 30min, the mass concentration 2% of described Fluohydric acid., and the mass concentration of described nitric acid is respectively 4%；
C () lubricates: do not have crannied steel pipe surfaces externally and internally brushing lubricant after detection in step (b), be placed in 200 DEG C of bakings
Dry；Described lubricant comprises 1 part of No. 3 industrial fat and 8 parts of saturated limewaters (parts by weight)；
(d) cold-drawn/cold rolling: the steel pipe obtained in step (c) is carried out cold rolling in cold mill complex, cold working in cold-rolled process
Deformation amount controlling is within 60%；
(e) pickling for the second time: carry out pickling in the salpeter solution that steel pipe mass concentration is 4% that will obtain in step (d)
30 minutes；
(f) heat treatment: be placed in 820 DEG C of insulations 45 minutes, natural cooling subsequently by obtaining steel pipe in step (e)；
G () pickling & for the third time checks: the steel pipe obtained in step (f) described Fluohydric acid. and nitric acid mixed solution are carried out
Pickling, pickling time is 40min；Put in storage after carrying out Non-Destructive Testing after washing and drying again.
Embodiment 2
The present embodiment provides a kind of ferritic stainless seamless steel tube, and its element weight percent is as follows, C:0.03%, Si:
1.1%, Mn:1%, P:0.03%；S:0.02%, Cr:19%, Ti:0.4%, N:0.025%, Cu:0.25%,
Al:1.2%, surplus is Fe；Its preparation method comprises the following steps:
(a) hot-puncturing process: first stamp internal point (centering when being easy to bore a hole) at pipe end face, be subsequently placed in heating furnace
It is heated to 800 DEG C with the speed of 8 DEG C/min, then is heated to 1160 DEG C with 20 DEG C/min speed by 800 DEG C, be incubated 30 minutes,
Controlling the front compression ratio in top is 5.0% perforation, subsequently natural cooling；
B () pickling & for the first time checks: the steel pipe Fluohydric acid. and the nitric acid mixed solution that prepare in step (a) are carried out pickling,
Use endoscope, visual mode that its surfaces externally and internally carries out Crack Detection respectively again, confirm that the surfaces externally and internally of steel pipe has free from flaw；
Described pickling time is 60min, the mass concentration 3% of described Fluohydric acid., and the mass concentration of described nitric acid is respectively 7%；
C () lubricates: do not have crannied steel pipe surfaces externally and internally brushing lubricant after detection in step (b), be placed in 250 DEG C of bakings
Dry；Described lubricant comprises 3 parts of No. 3 industrial fat and 15 parts of saturated limewaters (parts by weight)；
(d) cold-drawn/cold rolling: the steel pipe obtained in step (c) is carried out cold rolling in cold mill complex, cold working in cold-rolled process
Deformation amount controlling is within 60%；
(e) pickling for the second time: carry out pickling in the salpeter solution that steel pipe mass concentration is 5% that will obtain in step (d)
30 minutes；
(f) heat treatment: be placed in 780 DEG C of insulations 75 minutes, natural cooling subsequently by obtaining steel pipe in step (e)；
G () pickling & for the third time checks: the steel pipe obtained in step (f) described Fluohydric acid. and nitric acid mixed solution are carried out
Pickling, pickling time is 40min；Put in storage after carrying out Non-Destructive Testing after washing and drying again.
Embodiment 3
A kind of ferritic stainless seamless steel tube of the present embodiment offer, its element weight percent following C:0.03%, Si:1.0%,
Mn:1%, P:0.03%；S:0.02%, Cr:18%, Ti:0.3%, N:0.025%, Cu:0.25%, Al:1.0%,
Surplus is Fe；Its preparation method comprises the following steps:
(a) hot-puncturing process: first stamp internal point (centering when being easy to bore a hole) at pipe end face, be subsequently placed in heating furnace
It is heated to 800 DEG C with the speed of 10 DEG C/min, then is heated to 1155 DEG C with 30 DEG C/min speed by 800 DEG C, be incubated 15 minutes,
Controlling the front compression ratio in top is 4.8% perforation, subsequently natural cooling；
B () pickling & for the first time checks: the steel pipe Fluohydric acid. and the nitric acid mixed solution that prepare in step (a) are carried out pickling,
Use endoscope, visual mode that its surfaces externally and internally carries out Crack Detection respectively again, confirm that the surfaces externally and internally of steel pipe has free from flaw；
Described pickling time is 1h, the mass concentration 2.5% of described Fluohydric acid., and the mass concentration of described nitric acid is respectively 7%；
C () lubricates: do not have crannied steel pipe surfaces externally and internally brushing lubricant after detection in step (b), be placed in 220 DEG C of bakings
Dry；Described lubricant comprises 2 parts of No. 3 industrial fat and 10 parts of lime water；
(d) cold-drawn/cold rolling: the steel pipe obtained in step (c) is carried out cold rolling in cold mill complex, cold working in cold-rolled process
Deformation amount controlling is within 60%；
(e) pickling for the second time: carry out pickling in the salpeter solution that steel pipe mass concentration is 4.5% that will obtain in step (d)
40 minutes；
(f) heat treatment: be placed in 800 DEG C of insulations 50 minutes, natural cooling subsequently by obtaining steel pipe in step (e)；
G () pickling & for the third time checks: the steel pipe obtained in step (f) described Fluohydric acid. and nitric acid mixed solution are carried out
Pickling, pickling time is 40min；Put in storage after carrying out Non-Destructive Testing after washing and drying again.
Above-described embodiment, only for technology design and the feature of the explanation present invention, its object is to allow the person skilled in the art can
Understand present disclosure and implement according to this, can not limit the scope of the invention with this, all according to spirit of the invention
The equivalence change made or modification, all should contain within protection scope of the present invention.
Claims (3)
1. a preparation method for ferritic stainless seamless steel tube, the element weight percent of described ferritic stainless seamless steel tube is as follows, C :≤0.03%, Si:0.7 ~ 1.1%, Mn :≤1%, P :≤0.03%；S :≤0.02%, Cr:17 ~ 19%, Ti:0.2 ~ 0.4%, N :≤0.025%, Cu :≤0.25%, Al:0.8 ~ 1.2%, surplus is Fe；It is characterized in that, it comprises the following steps:
A () hot-puncturing process: pipe is placed in 1150 ~ 1160 DEG C and is incubated 30 ~ 60 minutes, before controlling top, compression ratio is 4.5 ~ 5.0% perforation, natural cooling subsequently；
B () pickling for the first time is checked: the steel pipe Fluohydric acid. prepared in step (a) and nitric acid mixed solution carry out pickling, then uses endoscope, visual mode that its surfaces externally and internally carries out Crack Detection respectively, confirm that the surfaces externally and internally of steel pipe has free from flaw；Described pickling time is 30 ~ 60min, the mass concentration 2 ~ 3% of described Fluohydric acid., and the mass concentration of described nitric acid is respectively 4 ~ 7%；
C () lubricates: do not have crannied steel pipe surfaces externally and internally brushing lubricant after detection in step (b), be placed in 200 ~ 250 DEG C of drying；Described lubricant comprises industry fat and lime water；
D () is cold rolling: carry out cold rolling in cold mill complex by the steel pipe obtained in step (c), and in cold-rolled process, cold deformation controls within 60%；
(e) pickling for the second time: carry out pickling in the salpeter solution that steel pipe mass concentration is 4 ~ 5% that will obtain in step (d)；
(f) heat treatment: be placed in 780 ~ 820 DEG C of insulations 45 ~ 75 minutes, natural cooling subsequently by obtaining steel pipe in step (e)；
G () pickling & for the third time checks: the steel pipe obtained in step (f) described Fluohydric acid. and nitric acid mixed solution are carried out pickling, and pickling time is 30 ~ 60min；Put in storage after carrying out Non-Destructive Testing after washing and drying again.
The preparation method of ferritic stainless seamless steel tube the most according to claim 1, it is characterised in that: described lubricant comprises the component of following parts by weight: 1 ~ 3 part of No. 3 industrial fat and 8 ~ 15 parts of lime water.
The preparation method of ferritic stainless seamless steel tube the most according to claim 1, it is characterized in that: in described step (a), first stamp internal point at pipe end face, be subsequently placed in heating furnace and be heated to 800 DEG C with the speed of 8 ~ 10 DEG C/min, then with 20 ~ 30 DEG C/min
Speed is heated to 1150 ~ 1160 DEG C.
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| DE102016111591A1 (en) | 2016-06-24 | 2017-12-28 | Sandvik Materials Technology Deutschland Gmbh | A method of forming a ferromagnetic FeCrAl alloy billet into a pipe |
| US11724299B2 (en) * | 2017-12-27 | 2023-08-15 | Sandvik Intellectual Property Ab | Method for straightening of a FeCrAl alloy tube |
| CN108176728B (en) * | 2018-01-23 | 2019-06-07 | 苏州钢特威钢管有限公司 | The preparation method of 1Cr25Ti high chromium content ferrite stainless steel seamless pipe |
| CN111060670B (en) * | 2019-12-18 | 2022-06-10 | 江苏隆达超合金股份有限公司 | Method for detecting crack defects on inner surface of nickel-based alloy pierced billet by acid washing |
| CN112605148A (en) * | 2020-11-26 | 2021-04-06 | 衡阳鸿常机化有限公司 | Manufacturing process of seamless steel tube for seawater |
| CN114752941B (en) * | 2022-04-15 | 2023-01-10 | 江苏正泰不锈钢产业有限公司 | Preparation method of ferritic stainless steel seamless steel pipe |
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| CN1542156A (en) * | 2003-04-30 | 2004-11-03 | 王光煌 | High-silicon high-aluminium ferrite stainless steel and its application in preparation of heat-resisting steel pipe |
| CN101530869A (en) * | 2008-03-14 | 2009-09-16 | 钱乐中 | Process for manufacturing stainless-steel seamless steel pipe used for high-pressure boiler, boiler and heat-exchanger |
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| JPH11302786A (en) * | 1998-04-22 | 1999-11-02 | Nippon Steel Corp | Low yield ratio high strength thick seamless steel pipe and its production |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1542156A (en) * | 2003-04-30 | 2004-11-03 | 王光煌 | High-silicon high-aluminium ferrite stainless steel and its application in preparation of heat-resisting steel pipe |
| CN101530869A (en) * | 2008-03-14 | 2009-09-16 | 钱乐中 | Process for manufacturing stainless-steel seamless steel pipe used for high-pressure boiler, boiler and heat-exchanger |
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