CN1977059A - Super high strength UOE steel pipe and method for production thereof - Google Patents

Super high strength UOE steel pipe and method for production thereof Download PDF

Info

Publication number
CN1977059A
CN1977059A CNA2005800213134A CN200580021313A CN1977059A CN 1977059 A CN1977059 A CN 1977059A CN A2005800213134 A CNA2005800213134 A CN A2005800213134A CN 200580021313 A CN200580021313 A CN 200580021313A CN 1977059 A CN1977059 A CN 1977059A
Authority
CN
China
Prior art keywords
following
steel pipe
ceq
pcm
mother metal
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
Application number
CNA2005800213134A
Other languages
Chinese (zh)
Inventor
高桥伸彰
三浦充
山本昭夫
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Steel Corp
Original Assignee
Sumitomo Metal Industries Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Sumitomo Metal Industries Ltd filed Critical Sumitomo Metal Industries Ltd
Publication of CN1977059A publication Critical patent/CN1977059A/en
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0226—Hot rolling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
    • B21C37/06—Manufacture 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
    • B21C37/08—Making tubes with welded or soldered seams
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/10—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of tubular bodies
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Heat Treatment Of Steel (AREA)

Abstract

A UOE steel pipe for use in linepipe having an ultrahigh strength in the circumferential direction of the pipe of at least 750 MPa and at most 900 MPa and having improved toughness in the base metal and weld heat affected zone along with improved joint fracture properties and good circumferential weldability is manufactured from a hot-rolled steel plate having a composition comprising, in mass percent, C: 0.03 - 0.08%, Mn: 1.70 - 2.2%, S: at most 0.0020%, Ti: 0.005 - 0.025%, N: at most 0.0050% and having a carbon equivalent (Ceq) as defined below of at least 0.50% and a weld cracking parameter (Pcm) as defined below of at most 0.24% wherein the temperature at the completion of water cooling after hot rolling is 350 DEG C or higher: Ceq = C + Mn / 6 + Cr + Mo + V / 5 + Cu + Ni / 15 , Pcm = C + Si / 30 + Mn / 20 + Cu / 20 + Ni / 60 + Cr / 20 + Mo / 15 + V / 10 + B .

Description

Super high strength UOE steel pipe and manufacture method thereof
Technical field
The present invention relates to manage circumferential strength (TS) for 750MPa is above, 900MPa is following, strength and toughness balance excellence, super high strength UOE steel pipe and manufacture method thereof that the destruction characteristic of anti-the joint is also excellent.
Background technology
The hope of the cost of pipeline compression in recent years strengthens, and is background with the improvement of Manufacturing Technology, as pipeline (pipe line) and the steel pipe of laying realizes that this tendency of its high strength strengthens.In the past, the steel grade of having been standardized by API (API) reached X80 level (grade), and it is applied to pipeline.
(be equivalent to manage circumferential strength 〉=normalization 750MPa) and the research of practicability is advanced more high-intensity at present X100 level.When this ultrahigh-strength steel is applied to steel pipe that pipeline uses,, compare, require it to have quite high-caliber toughness with the level that existing steel is realized for the consideration of breach security.Therefore, just require can and to deposit the steel pipe of superstrength and superhigh tenacity and can make its steel of base metal.
Open in flat 8-209290 communique and the flat 8-209291 communique of Te Kai the spy, disclose the High Tensile Steel Tube that contains the high Mo set member of high Mn+, disclosed among the former is to implement temper, and disclosed among the latter is that enforcement 2 phase regions are rolling.
Te Kaiping 9-31536 communique discloses the High Tensile Steel Tube with the high Mo set member of Mn+ too, but its disclosed be the superstrength steel pipe that strength of parent is equivalent to the above X120 level of 950MPa.The spy opens and discloses steel strength in the 2000-199036 communique is the above superstrength steel pipe of 900MPa.Also disclose High Tensile Steel Tube in the Te Kaiping 8-199192 communique, but the martensite branch rate of its mother metal tissue of this steel pipe is more than 90%, also has the above ultrahigh-strength steel of strength of parent 900MPa to be used in an embodiment.
Here, steel strength is identical with steel of base metal intensity, and steel strength is the pipe circumferential strength in the circumferential result who measures of pipe in addition.
Summary of the invention
But above-mentioned prior art general idea all is to guarantee intensity, and is fully not open about the toughness of the toughness of mother metal and joint heat affected zone (HAZ).The high-strength steel high-strength steel special requirement, that fully satisfy isostatic strength and toughness characteristic and the destruction characteristic of anti-joint that surpasses the X80 level does not still exist at least.In fact, the present invention as object about joint destruction characteristic in the strength range and flexible both sides, all not mentioned in each above-mentioned patent documentation.
According to the present invention,,, carbon equivalent (Ceq) always do not answered the high scope of exhausted and being in for the destruction characteristic of anti-joint that makes the UOE steel pipe improves.Thus, can make the UOE steel pipe inherent phenomenon of carrying out submerged arc welding (submerged arc welding), the HAZ when promptly welding is softening further to be reduced.
On the other hand, if all weldabilities when considering that pipeline is on-the-spot and laying, then requirement can realize the isostatic composition design of low-welding crack Sensitivity Index (Pcm).
In addition, along with steel becomes high strength, the toughness reguirements of HAZ and mother metal is also uprised.About this point, especially, the HAZ flexible must reduce Ti and N for improving, need to reduce S simultaneously for the raising of base metal tenacity.
By considering above some composition design, find make that intensity rank is controlled at more than the 750MPa, during the UOE steel pipe that (is equivalent to the X100 level) below the 900MPa, it has very good destruction characteristic of anti-joint the and toughness.At this moment, confirm, then can satisfy this very high toughness value of anti-destruction of the desired 150J of X100 level if making the cooling of the water-cooled after the hot rolling stop temperature being in more than 350 ℃.
From a side, the present invention is a kind of UOE steel pipe: the mother metal chemical constitution is in quality %, contain C:0.03～0.08%, Mn:1.70～2.2%, below the S:0.0020%, Ti:0.005～0.025%, below the N:0.0050%, according to circumstances also contain at least a kind of element selecting to (iv) from following (i), surplus is made up of iron and unavoidable impurities, following defined carbon equivalent (Ceq) is more than 0.50%, welding crack sensibility index (Pcm) is below 0.24%, the pipe circumferential strength is more than the 750MPa, below the 900MPa
Ceq＝C+Mn/6+(Cr+Mo+V)/5+(Cu+Ni)/15，
Pcm＝C+Si/30+Mn/20+Cu/20+Ni/60+Cr/20+Mo/15+V/10+B，
Ceq=carbon equivalent, Pcm=welding crack sensibility index, each symbol of element meaning in the formula is the content of this element in quality %,
(i) a kind or 2 kinds below Si:0.05～0.50% and the Al:0.06%,
(ii) Cu:1.0% is following, Ni:2.0% following, Cr:1.0% is following, Nb:0.1% is following and V:0.1% is following more than a kind or 2 kinds,
(iii) below the Mo:1.0%,
(iv) below the Ca:0.005%.
The destruction toughness that UOE of the present invention steel tube place requires to demonstrate is that mother metal and welding heat affected zone (HAZ) the pendulum absorption-10 ℃ under can reach more than the 150J.
From the another side, the present invention is that the above-mentioned carbon equivalent of a kind of manufacturing (Ceq) is more than 0.50, connecing crack sensitivity index (Pcm) is below 0.24%, the pipe circumferential strength is the manufacture method of the UOE steel pipe that 750MPa is above, 900MPa is following: be after the steel plate that will have above-mentioned chemical constitution carries out hot rolling, making water-cooled stop temperature is to carry out water-cooled more than 350 ℃, the steel plate that obtains is carried out U type extruding and the O type pushes, obtain the UOE steel pipe through welding and expander again.The welding of UOE steel pipe is followed ordinary method and is undertaken by submerged arc welding.
According to the present invention, to create the intensity that 750MPa is above, 900MPa is following through the steel pipe that carbon equivalent high (Ceq) is regulated, carry out softening being minimized of HAZ of the UOE steel tube place inherent joint of submerged arc welding thus, the destruction characteristic of anti-joint of UOE steel pipe significantly improves.On the other hand, by reducing the content of S, Ti, N, can guarantee the toughness of mother metal and HAZ.
UOE steel pipe of the present invention owing to can make by the condition identical with UOE steel pipe below the existing X80 level, so can either keep and the equal production efficiency of existing UOE steel pipe, can be made the UOE steel pipe of superstrength again.Therefore, can significantly reduce the manufacturing cost of the UOE steel pipe of superstrength.
Description of drawings
Fig. 1 represents the graphic representation of relation of the toughness (10 ℃ pendulum absorb can) of S content and mother metal in the steel.
Embodiment
In order to make the also unspecified ultrahigh-strength steel of API specification be applicable to actual pipeline, after (1) breach security and (2) all weldabilities are listed in consideration, just must provide pipeline with the performance that is harmonious with the laying environment.
If particularly the long distance line of transport gas and oil has the generation of destruction must cause Serious Accident.Brittle rupture and ductile failure are arranged on the destructive mode.In brittle rupture, destroy with respect to propagating with the ultra-high speed more than the 500m/sec, little to 300m/sec from the destruction velocity of propagation of ductile failure.Therefore, be applicable to actual pipeline in order to make steel pipe, mother metal has the toughness that develops into as the ductile failure under environment for use be major premise.
In addition, require level, advocate as the HLP council (the damage study mechanism of Japan) about flexible, even when having the high speed ductile failure to take place, this destructive is propagated also and will be stoped with interior obtaining at certain distance, therefore along with steel becomes high strength, just needs higher destruction toughness value.Needed destruction toughness value (under 10 ℃ pendulum absorb can) also exists with ... the size of grade, steel pipe of intensity and pressure inside etc., but in X100 level steel, is not the desired 40～50J of general steel (APIX70 level), but requires more than 150J.Therefore, X100 level steel requires high-intensity so high destruction toughness value that also requires simultaneously to have.
About breach security, can estimate by the fracture position when pipe circumferentially applies power.This fracture position roughly is divided into three kinds of mother metal, welding metal portion and welding heat affected zones (HAZ).Mother metal when fracture,, then develop into ductile failure if fully guaranteed toughness as above-mentioned.When welding metal portion ruptures, the situation that becomes ductile failure is arranged also, but the situation that brittle rupture takes place is in the great majority.Therefore, need definitely prevent the fracture of welding metal portion.In general, be more than mother metal, (to be in excessively) fracture that prevents welding metal portion by the intensity that makes welding metal.This phenomenon of the fracture of HAZ portion especially can appear in the above high-strength steel of 700MPa.
Steel of the present invention prevents to have great effect what this HAZ ruptured especially.Be considered to prevent that the method for HAZ fracture from having as follows:
(1) make the intensity of welding metal portion be in strength of parent above (guaranteeing excessively),
(2) do one's utmost to reduce welding heat input for the area that dwindles HAZ,
(3) intensity of raising HAZ,
(4) control weld part shape is exactly the stress concentration that reduces the welding toe.
In the present invention, improve Ceq in order to ensure the intensity of HAZ.HAZ portion be since heat affecting and once melting resolidification or phase transformation tissue.For the intensity that makes HAZ rises, effectively way is to make composition abundance (Ceq and Pcm are increased together) or the input heat is reduced.The input heat is set in the MIN input heat that can guarantee the weld part shape and get final product, but if will make the composition abundance, then can have such difficult point, all weldability reductions when causing the scene to carry out connection between the steel pipe exactly.
In the present invention, thus by realizing that high Ceq suppresses the softening of HAZ, guaranteeing high strength, another aspect, be controlled at Pcm to a certain degree below, thereby keep all weldabilities well.
Guarantee that about the HAZ flexible it is also very important to regulate N and Ti, by making its balance optimizing, can distinguish the toughness deterioration that can prevent to be accompanied by the intensity rising and come.
In the past, be the manufacturing of the ultrahigh-strength steel more than the 750MPa for TS, generally be suitable for TMCP (Thermo-Mechanical Control Process), make water-cooled after the hot rolling stop temperature and be in (example that is reported as room temperature is also a lot) below 200 ℃.This is the fundamental property in order to ensure intensity and toughness etc.
In the present invention, although be the above ultrahigh-strength steel of 750MPa, consider breach security, its manufacturing still will be grouped into the one-tenth of Ceq 〉=0.50%, makes water-cooled after the hot rolling stop temperature and is in more than 350 ℃.Thus, destroying near the connector portions when destroy taking place, can reach high-intensity high-tenacity and deposit.
In addition, do not adopt extremely that low water-cooled stops, can making mother metal deformability, be that uniform elongation further improves.Therefore, manufacture method of the present invention and UOE steel pipe are very effective from the viewpoint of breach security.
So-called uniform elongation (boundary unit elongation) is meant and arrives in the amount of plastic deformation that reaches crest in tension test.Therefore, the uniform elongation of so-called mother metal is big, just means that its amount of plastic deformation that reaches TS is big, the breach security height just in case the sharply situation of rising of pressure is arranged in the operation of pipeline.From this point, the uniform elongation of preferred mother metal is more than 5.0%.
Fig. 1 is illustrated in the steel of X100 level, the graphic representation of the relation of the toughness of S and mother metal (pendulum under 10 ℃ absorbs energy).As shown in Figure 1, the toughness levels of mother metal is significantly improved owing to hang down Sization.By this result as can be known, when requiring ultrahigh-strength steel to have height destruction toughness value, effectively way is to regulate S.
In the present invention, because needed destruction toughness value is 150J, S will be below 20ppm.In addition,, for example require to be 200J when above, S is got final product below 14ppm when requiring the high toughness value that destroys.
The present invention can provide a kind of UOE steel pipe, as connector portions HAZ fracture prevent and the high uniform elongation of mother metal guarantee that these lean on the insurmountable problem of existing manufacture method, all welding propertys when also having pipe laying, it can both all satisfy.
According to the present invention, by identical with ordinary steel below the APIX80 level and water-cooled stops the UOE steel pipe that temperature is made as the TMCP more than 350 ℃, for make its satisfy the APIX100 level suitable intensity and carbon equivalent (Ceq) is made as more than 0.50%, and (Pcm) is suppressed at below 0.24% with the welding crack sensibility index, can guarantee all weldabilities thus.
The chemical ingredients of the mother metal among the present invention is composed as follows.
C：0.03～0.08％
C is the element that effectively promotes intensity, contains more than 0.03% for the intensity of giving the X100 level.On the other hand, reduce significantly, when the characteristic of the machinery that brings mother metal is with disadvantageous effect, also can encourage the surface spots of steel billet when C surpasses 0.08% flexible.Preferred C3 content is 0.03～0.05%.
Mn：1.70～2.2％
Mn is an effective elements aspect the reinforcement of steel and highly malleablized, in order to ensure intensity and toughness and contain more than 1.70%.But, when Mn surpasses 2.2% toughness of welded zone deterioration.Preferred L n content is 1.8～2.0%.
Below the S:0.0020%
S is one of element that needs for the toughness of mother metal guarantees restriction, if S surpasses 0.0020%, then can not guarantee the destruction toughness value of necessary mother metal.Illustrated as relevant Fig. 1, S will for example below 0.0014%, also can further limit according to the desired destruction toughness value of mother metal.
Ti：0.005～0.025％
The generation of Ti by TiN suppresses the crystal grain of HAZ grows up, and has the effect that the toughness of making improves.At least need 0.005% Ti for this reason.On the other hand, if Ti surpasses 0.025%, then dissolving the N amount increases HAZ toughness deterioration.Preferred Ti content is 0.005～0.018%.
Below the N:0.0050%
N and V, Ti etc. form nitride, can improve hot strength effectively.But,, then can form carbonitride and cause that the flexible of mother metal and HAZ reduces with Nb, V, Ti if N surpasses 0.0050%.When HAZ require level high the time, preferred N is extremely low below 0.0035%.
Except above-mentioned basal component, in order to reach the high tenacity that high strength more than the X100 level also has mother metal and HAZ, carbon equivalent of mother metal (Ceq) and welding crack sensibility index (Pcm) become important factors.
More than the Ceq:0.50% of mother metal
Stopping temperature in water-cooled and be set among the TMCP more than 350 ℃, in order to guarantee the strength of parent more than the X100 level, is more than 0.50% and make the carbon equivalent (Ceq) of mother metal.If can guarantee the steel of base metal intensity that the X100 level is above, then the upper limit of Ceq is not particularly limited, but Ceq is preferably below 0.55%.Ceq expresses (each symbol of element meaning in the formula is the content of this element in quality %) by following formula:
Ceq＝C+Mn/6+(Cr+Mo+V)/5+(Cu+Ni)/15。
Below the Pcm:0.24% of mother metal
For under high strength and be also included within when welding week and guarantee high tenacity, be below 0.24% and will make the welding crack sensibility index (Pcm) of mother metal, and so design the composition of steel.The lower limit of Pcm does not have special stipulation, but is generally more than 0.16%.Pcm expresses (each symbol of element meaning in the formula is the content of this element in quality %) by following formula:
Pcm＝C+Si/30+Mn/20+Cu/20+Ni/60+Cr/20+Mo/15+V/10+B。
As UOE steel pipe of the present invention, the Ceq and the Pcm of welding metal are not particularly limited.
Also have, in this manual, when only recording and narrating to " Ceq " and " Pcm ", the meaning is the mother metal that has comprised HAZ, i.e. the Ceq of the steel pipe integral except welding metal and Pcm.
The pipe circumferential strength of UOE steel pipe of the present invention is more than the 750MPa, below the 900MPa.This regulation be that the strength level of steel pipe is the level of X100 level.In the present invention, be grouped into by as above-mentioned, being controlled to, the water-cooled of utilization after with hot rolling stop temperature being made as more than 350 ℃, with the identical method of existing more low intensive UOE steel pipe, the super high strength UOE steel pipe of X100 grade can be made, and necessary mother metal and the destruction toughness of HAZ can be guaranteed.
The mother metal of UOE steel pipe of the present invention also can contain any composition of selecting more than a kind or 2 kinds again from the group of following (i)～(iv).
(i) Si:0.05～0.50%, below the Al:0.060%
Si and Al have desoxydatoin, preferably allocate at least a kind in them.
Si makes the effect of steel reinforcement in addition except as the reductor.To be lower than 0.05% deoxidation insufficient when Si content.If Si surpasses 0.5%, then there are a large amount of lath martensites to generate at HAZ, make deterioration at the bottom of the HAZ toughness utmost point, be the reduction of the mechanical properties of steel pipe accordingly.Si content can be in 0.05～0.50% scope, and its decision needs the balance of the thickness of slab of consideration and steel plate.
Al and Si play a part reductor equally, but will be could fully obtain this effect below 0.06%.Excessive interpolation is not preferred from economic face except making on-the-spot all weldability deteriorations yet.
(ii) Cu:1.0% is following, Ni:2.0% following, Cr:1.0% is following, Nb:0.1% is following, below the V:0.1%
These elements can improve hardenability by a spot of interpolation, and the consequent is that the improvement to various characteristics exerts an influence.
Cu can increase the tissue variation that effect is brought by solution strengthening and hardenability, realizes the raising of intensity on not obvious infringement flexible basis.If Cu surpasses 1.0%, then the deleterious Cu crackle of billet surface protective layer (checking) is taken place, for it is prevented and need the steel billet low-temperature heat can the manufacturing scope be restricted.
Ni is the same with Cu, can increase the tissue variation that effect is brought by solution strengthening and hardenability, realizes the raising of intensity on not obvious infringement flexible basis.The mother metal that suppresses after the thermal flexure processing and the effect of HAZ flexible deterioration are arranged simultaneously.The interpolation that is higher than 2.0% Ni can make cost improve, and except impracticable, also makes on-the-spot all weldability deteriorations.
Cr is identical with Cu and Ni, can increase the tissue variation that effect is brought by solution strengthening and hardenability, realizes the raising of intensity on not obvious infringement flexible basis, but if Cr surpasses 1.0%, then makes the toughness deterioration of HAZ.
The huge effect that Nb and V bring is that based on the intensity rising of precipitation strength and hardenability increase effect, perhaps the flexible of accompanying crystallization grain miniaturization improves.If its addition, then becomes the reason of the toughness reduction that makes HAZ all above 0.1%.
Add this 1 or during the element more than 2 kind, preferred content is that Cu:0.50% is following, Ni:0.80% is following, Cr:0.40% is following, Nb:0.06% is following, below the V:0.06%.
(iii) below the Mo:1.0%
Mo can improve the intensity of mother metal weld part effectively.If the addition of Mo is too much, then cause the toughness deterioration of on-the-spot all weldabilities and HAZ, therefore the upper limit is made as 1.0%.Preferred content when adding Mo is below 0.50%.
(iv) below the Ca:0.005%.
Ca has the effect of control inclusion morphology, is exactly to make the inclusion balling specifically, can prevent hydrogen induced cracking (HIC) and stratiform (lamellar) be full of cracks.But it is saturated 0.005% its effect.
In order to make UOE steel pipe of the present invention, the steel billet of the chemical constitution that is adjusted into afore mentioned rules is carried out hot rolling, after finish rolling finished, carrying out water-cooled, to stop temperature be water-cooled more than 350 ℃.By habitual U type extruding and the extruding of O type the hot-rolled steel sheet that obtains is configured as body, follows, from interior outside butt welding portion.This welding is undertaken by submerged arc welding.By carrying out expander behind the welding tube-making to improve circularity.Expander can be undertaken by mechanical expander or hydraulic pressure expander.
In the manufacture method of UOE steel pipe of the present invention,, be not particularly limited about the manufacturing process of UOE steel pipe except the water-cooled condition after the hot rolling.Implementing the manufacturing identical with UOE steel pipe below the existing X80 level gets final product.However, still can produce the superstrength of X100 level (the pipe circumferential strength is more than the 750MPa, below the 900MPa), simultaneously the UOE steel pipe of anti-destruction characteristic excellence.
Next, be described more specifically the present invention, but embodiment does not limit the present invention nothing but example by embodiment.
Embodiment
The steel billet that will have the chemical ingredients shown in the table 1, heating remains on after 1100～1200 ℃, carries out finish rolling after thickness of slab reaches 20mm at 700～850 ℃, stops temperature with the water-cooled shown in the table 1 and carries out water-cooled, then air cooling is made the hot-rolled steel sheet of mother metal thus to normal temperature.By cold U type extruding, the extruding of O type is configured as body with this mother metal steel plate then.Then, the submerged arc welding butt welding portion by habitual carries out mechanical expander again.So produce the UOE steel pipe of external diameter 910mm (36 inches), wall thickness 20mm, long 1200mm.
The joint tensile properties of the UOE steel pipe of the intensity of mother metal and toughness and making and the result of all welding tests are summarised in the table 1.Particularly, strength of parent and joint tension fracture position are confirming that on the effect of the present invention be an important project.
Toughness and intensity about mother metal, be that the UOE steel pipe that never comprises weld part and HAZ upwards extracts impact shock test sheet (JIS4 number) and tension test sheet (ASTM diameter 6.35mm pole test film) in week, the pendulum of trying to achieve under-10 ℃ absorbs energy (record and narrate in the table and be VE-10 ℃), tensile strength (TS) and uniformly extension (boundary unit elongation).
Joint straight draw test is that the weld part with the UOE steel pipe is drilled into central authorities, is so circumferentially extracting the tension test sheet, and the butt welded seam reinforcement is implemented tension test, confirms its intensity and fracture position.In addition, from HAZ (welding heat affected zone) the extraction shock test sheet (JIS4 number) of UOE steel pipe, the pendulum of trying to achieve under-10 ℃ absorbs and can (record and narrate in the table and be VE-10 ℃).The evaluation of welding property is by actual week welding UOE steel pipe, implements the Y crack test, sees whether at-10 ℃ crackle takes place.Be expressed as during visible crack " * ", be not expressed as " zero " when seeing.
In the No.1 and 20～24 as embodiment, the intensity of mother metal and tough sexual satisfaction defined terms by making the composition optimizing, rupture and can reach mother metal in joint straight draw test simultaneously, and the joint destruction characteristic is also excellent.In addition, all weldabilities are also good.
On the other hand, in comparative example, can not satisfy suitable intensity, toughness or other performance.Particularly in No.10,12 and 16～18, the toughness of HAZ extremely reduces.
Table 1
No Mother metal Water-cooled stops temperature Mother metal Zhou Fangxiang intensity VE-10℃ (J) Joint straight draw test All weldabilities Reference
C Mn S Ti N Si Cu Ni Cr Mo Nb V Al Ceq Pcm TS UEL BM (week) HAZ TS Disrumpent feelings position
mass％ ppm mass％ ppm mass％ mass％ ℃ MPa ％ MPa
1 0.06 1.90 10 0.015 45 0.15 0.20 0.20 0.15 0.35 0.03 0.03 0.02 0.51 0.21 420 821 6.2 212 204 825 BM ○ Real
2 0.06 1.90 10 0.015 45 0.15 0.20 0.20 0.15 0.35 0.03 0.03 0.02 0.51 0.21 300* 868 4.9 215 200 868 BM ○ Comparative example
3 0.06 1.90 10 0.015 45 0.15 0.20 0.20 0.15 0.35 0.03 0.03 0.02 0.51 0.21 RT * 911 * 4.5 222 203 898 HAZ ○
4 0.10 * 1.90 8 0.017 38 0.14 0.19 0.21 0.15 0.25 0.03 0.04 0.03 0.53 0.23 420 904 * 7.3 168 147 838 BM ×
5 0.02 * 1.95 11 0.015 39 0.15 0.20 0.30 0.15 0.25 0.04 0.04 0.03 0.49 * 0.18 470 749 * 3.8 150 155 738 BM ○
6 0.07 1.65 11 0.014 42 0.20 0.30 0.30 0.30 0.25 0.03 0.03 0.03 0.50 0.22 430 800 5.1 147 151 801 BM ○
7 0.06 2.20 10 0.015 45 0.15 0.20 0.20 0.15 0.35 0.03 0.03 0.02 0.57 0.25 * 450 940 * 5.1 225 231 920 HAZ ×
8 0.06 1.90 21 * 0.015 45 0.15 0.20 0.20 0.15 0.35 0.03 0.03 0.02 0.51 0.21 390 842 6.7 125 140 841 BM ○
9 0.06 1.90 10 0.027 * 45 0.15 0.20 0.20 0.15 0.35 0.03 0.03 0.02 0.51 0.21 450 833 5.4 210 119 822 HAZ ○
10 0.06 1.90 9 0.015 72 * 0.15 0.20 0.20 0.15 0.35 0.03 0.03 0.02 0.51 0.21 420 819 4.2 139 99 800 HAZ ○
11 0.06 1.90 12 0.015 51 * 0.03 * 0.15 0.25 0.15 0.35 0.03 0.03 0.02 0.49 * 0.21 450 745 * 6.4 140 135 749 BM ○
12 0.06 1.90 11 0.015 37 0.60 * 0.15 0.25 0.15 0.35 0.03 0.03 0.02 0.50 0.25 * 480 790 6.1 167 78 789 BM ×
13 0.06 1.90 10 0.015 50 0.15 1.1 * 0.60 0.03 0.02 0.03 0.03 0.02 0.50 0.26 * 450 811 6.4 170 153 813 BM ×
14 0.05 1.80 10 0.015 45 0.15 0.05 2.2 * 0.03 0.02 0.03 0.03 0.03 0.51 0.22 450 833 5.7 244 242 832 BM ×
15 0.05 1.80 8 0.015 43 0.15 0.05 0.04 1.1 * 0.02 0.03 0.03 0.03 0.58 0.25 * 450 921 * 4.4 221 118 891 HAZ ×
16 0.05 1.80 17 0.015 44 0.15 0.05 0.04 0.05 1.1 * 0.03 0.03 0.03 0.59 0.26 * 450 933 * 5.2 151 88 912 HAZ ×
17 0.06 1.92 15 0.015 49 0.15 0.20 0.20 0.15 0.35 0.11 * 0.03 0.02 0.51 0.21 400 834 5.3 177 87 821 BM ○
18 0.06 1.89 10 0.015 32 0.15 0.20 0.20 0.15 0.35 0.03 0.12 * 0.02 0.53 0.24 450 834 5.5 157 78 830 BM ○
19 0.06 1.89 10 0.015 42 0.15 0.20 0.20 0.15 0.35 0.03 0.03 0.08 * 0.53 0.24 450 822 5.9 178 190 810 BM ×
20 0.06 1.90 10 0.015 45 0.15 0.30 0.30 0.03 0.35 0.03 0.03 0.02 0.50 0.23 450 844 5.3 178 186 840 BM ○ Embodiment
21 0.06 1.90 10 0.015 35 0.10 0.30 0.50 0.03 0.30 0.03 0.01 0.02 0.52 0.22 450 850 5.5 200 205 848 BM ○
22 0.06 2.00 10 0.014 40 0.10 0.30 0.30 0.03 0.35 0.03 0.01 0.02 0.51 0.23 360 871 5.5 194 188 880 BM ○
23 0.06 2.05 4 0.015 40 0.15 0.30 0.30 0.03 0.35 0.03 0.01 0.02 0.51 0.23 420 858 6.2 250 253 855 BM ○
24 0.06 1.95 10 0.012 35 0.05 0.15 0.30 0.15 0.35 0.04 0.04 0.03 0.52 0.21 410 830 6.3 220 240 831 BM ○
(notes) TS: tensile strength, UEL: boundary unit elongation, BM: mother metal, HAZ: heat affected zone, *Condition, (week): Zhou Fangxiang, reality: embodiment that the scope of the invention is outer

Claims (3)

1. UOE steel pipe, it is characterized in that, the mother metal chemical constitution is in quality %, contain that C:0.03～0.08%, Mn:1.70～2.2%, S:0.0020% are following, Ti:0.005～0.025%, below the N:0.0050%, surplus is made of iron and unavoidable impurities, by make following defined carbon equivalent Ceq be more than 0.50%, and welding crack sensibility indices P cm be below 0.24%, thereby pipe Zhou Fangxiang intensity is more than the 750MPa, below the 900MPa
Ceq＝C+Mn/6+(Cr+Mo+V)/5+(Cu+Ni)/15；
Pcm＝C+Si/30+Mn/20+Cu/20+Ni/60+Cr/20+Mo/15+V/10+B；
Ceq=carbon equivalent, Pcm=welding crack sensibility index, each symbol of element in the formula is represented the content of this element in quality %.
2. UOE steel pipe according to claim 1 is characterized in that, described mother metal chemical constitution is in quality %, also contains at least a kind of element selecting to (iv) from following (i):
(i) a kind or 2 kinds below Si:0.05～0.50% and the Al:0.06%,
(ii) Cu:1.0% is following, Ni:2.0% following, Cr:1.0% is following, Nb:0.1% is following and V:0.1% is following more than a kind or 2 kinds,
(iii) below the Mo:1.0%,
(iv) below the Ca:0.005%.
3. the manufacture method of a UOE steel pipe, it is characterized in that, be to make by the carbon equivalent Ceq of following definitions reaching welding crack sensibility indices P cm more than 0.50 below 0.24%, the pipe circumferential strength is more than the 750MPa, the manufacture method of the UOE steel pipe that 900MPa is following, wherein, the mother metal chemical constitution is contained C:0.03～0.08% in quality %, Mn:1.70～2.2%, below the S:0.0020%, Ti:0.005～0.025%, below the N:0.0050%, according to circumstances also contain at least a kind of element selecting to (iv) from following (i), after the steel plate that surplus is made of iron and unavoidable impurities carries out hot rolling, water-cooled is stopped temperature being made as and carrying out water-cooled more than 350 ℃, the steel plate that obtains is carried out extruding of U type and the extruding of O type, then through welding and expander and obtain the UOE steel pipe
Ceq＝C+Mn/6+(Cr+Mo+V)/5+(Cu+Ni)/15；
Pcm＝C+Si/30+Mn/20+Cu/20+Ni/60+Cr/20+Mo/15+V/10+B；
Ceq=carbon equivalent, Pcm=welding crack sensibility index, each symbol of element meaning in the formula is the content of this element in quality %,
(i) a kind or 2 kinds below Si:0.05～0.50% and the Al:0.06%,
(ii) Cu:1.0% is following, Ni:2.0% following, Cr:1.0% is following, Nb:0.1% is following and V:0.1% is following more than a kind or 2 kinds,
(iii) below the Mo:1.0%,
(iv) below the Ca:0.005%.
CNA2005800213134A 2004-05-11 2005-05-10 Super high strength UOE steel pipe and method for production thereof Pending CN1977059A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2004141223 2004-05-11
JP141223/2004 2004-05-11

Publications (1)

Publication Number Publication Date
CN1977059A true CN1977059A (en) 2007-06-06

Family

ID=35320247

Family Applications (1)

Application Number Title Priority Date Filing Date
CNA2005800213134A Pending CN1977059A (en) 2004-05-11 2005-05-10 Super high strength UOE steel pipe and method for production thereof

Country Status (6)

Country Link
US (1) US20070240794A1 (en)
EP (1) EP1746175A4 (en)
JP (1) JPWO2005108636A1 (en)
CN (1) CN1977059A (en)
CA (1) CA2566425A1 (en)
WO (1) WO2005108636A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101578384B (en) * 2007-12-07 2011-06-15 新日本制铁株式会社 Steel with weld heat-affected zone having excellent CTOD properties and process for producing the steel
CN104894492A (en) * 2015-06-26 2015-09-09 山东钢铁股份有限公司 Ultralow-temperature, large-diameter and WPHY80-level steel plate special for three-way pipe fitting and production method of steel plate

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009014238A1 (en) * 2007-07-23 2009-01-29 Nippon Steel Corporation Steel pipes excellent in deformation characteristics and process for manufacturing the same
US8803023B2 (en) * 2007-11-29 2014-08-12 Isg Technologies Seam welding
JP2009235460A (en) * 2008-03-26 2009-10-15 Sumitomo Metal Ind Ltd High-strength uoe steel pipe excellent in earthquake-proof performance and low-temperature toughness of weld heat-affected zone
RU2011141268A (en) * 2009-03-12 2013-04-20 Сумитомо Метал Индастриз, Лтд. THICK-STEEL STEEL RESISTANT TO HYDROGEN CRACKING AND THE STEEL PIPE MADE BY UOE TECHNOLOGY
CN102428198A (en) * 2009-05-22 2012-04-25 杰富意钢铁株式会社 Steel material for high heat input welding
JP5505280B2 (en) * 2010-11-25 2014-05-28 Ｊｆｅスチール株式会社 Use limit prediction method of steel structure
JP5644436B2 (en) * 2010-12-03 2014-12-24 Ｊｆｅスチール株式会社 Deformation state evaluation method of cold-formed square steel pipe
CN105127237A (en) * 2015-09-19 2015-12-09 云南昆钢新型复合材料开发有限公司 Production method of double-metal abrasion-resistant composite pipe

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02250941A (en) * 1989-03-24 1990-10-08 Sumitomo Metal Ind Ltd Low carbon chromium-molybdenum steel and its manufacture
NO320153B1 (en) * 1997-02-25 2005-10-31 Sumitomo Metal Ind Stable with high toughness and high tensile strength, as well as manufacturing methods
WO1999005336A1 (en) * 1997-07-28 1999-02-04 Exxonmobil Upstream Research Company Ultra-high strength, weldable, boron-containing steels with superior toughness
JP2000119797A (en) * 1998-10-12 2000-04-25 Nippon Steel Corp High tensile strength steel material for welding, excellent in toughness in weld heat-affected zone, and its manufacture
JP4477707B2 (en) * 1999-03-10 2010-06-09 新日本製鐵株式会社 Ultra high strength steel pipe excellent in low temperature toughness and method for producing the same
JP3814112B2 (en) * 1999-10-15 2006-08-23 新日本製鐵株式会社 Super high strength steel pipe excellent in low temperature toughness of seam welded portion and manufacturing method thereof
JP3785376B2 (en) * 2002-03-29 2006-06-14 新日本製鐵株式会社 Manufacturing method of steel pipe and steel plate for steel pipe excellent in weld heat affected zone toughness and deformability
JP2003306749A (en) * 2002-04-19 2003-10-31 Nippon Steel Corp Method for manufacturing high strength steel tube of excellent deformability and steel plate for steel tube
JP4102103B2 (en) * 2002-05-20 2008-06-18 新日本製鐵株式会社 Manufacturing method of high strength bend pipe
JP3968011B2 (en) * 2002-05-27 2007-08-29 新日本製鐵株式会社 High strength steel excellent in low temperature toughness and weld heat affected zone toughness, method for producing the same and method for producing high strength steel pipe
JP4171267B2 (en) * 2002-09-05 2008-10-22 新日本製鐵株式会社 High strength welded steel pipe with excellent weld toughness and manufacturing method thereof

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101578384B (en) * 2007-12-07 2011-06-15 新日本制铁株式会社 Steel with weld heat-affected zone having excellent CTOD properties and process for producing the steel
CN104894492A (en) * 2015-06-26 2015-09-09 山东钢铁股份有限公司 Ultralow-temperature, large-diameter and WPHY80-level steel plate special for three-way pipe fitting and production method of steel plate
CN104894492B (en) * 2015-06-26 2017-04-19 山东钢铁股份有限公司 Ultralow-temperature, large-diameter and WPHY80-level steel plate special for three-way pipe fitting and production method of steel plate

Also Published As

Publication number Publication date
EP1746175A1 (en) 2007-01-24
CA2566425A1 (en) 2005-11-17
WO2005108636A1 (en) 2005-11-17
US20070240794A1 (en) 2007-10-18
JPWO2005108636A1 (en) 2008-03-21
EP1746175A4 (en) 2007-07-04

Similar Documents

Publication Publication Date Title
CN1977059A (en) Super high strength UOE steel pipe and method for production thereof
JP5776860B1 (en) Steel plates and line pipes for thick-walled high-strength line pipes with excellent sour resistance, crush resistance and low temperature toughness
KR101231270B1 (en) High-strength steel tube for low-temperature use with superior buckling resistance and toughness in weld heat-affected areas, and manufacturing method for same
JP5966730B2 (en) Abrasion resistant steel plate with excellent impact wear resistance and method for producing the same
RU2420599C1 (en) Bent pipe and procedure for its fabrication
JP5217556B2 (en) High strength steel pipe for low temperature excellent in buckling resistance and weld heat affected zone toughness and method for producing the same
WO2008007737A1 (en) Bend pipe and process for producing the same
JP4484123B2 (en) High strength and excellent base material for clad steel plate with excellent weld heat affected zone toughness
JP2007519819A (en) Steel sheets and steel pipes for ultra-high-strength line pipes excellent in low-temperature toughness and methods for producing them
CN1146784A (en) Weldable high-tensile steel excellent in low-temp. toughness
CN1265709A (en) Ultra-high strength, weldable steels with excellent ultra-low temperature toughness
CN1265711A (en) Ultra-high strength, weldable, essentially boron-free steels with superior toughness
JP4655670B2 (en) Manufacturing method of high strength welded steel pipe with low yield ratio and excellent weld toughness
JP7155703B2 (en) Thick steel plate for line pipe and manufacturing method thereof
CN1746326A (en) Needle ferrichrome-X70 pipeline steel with high crack-arresting toughenss and its production
JP5835625B2 (en) Polyolefin-coated UOE steel pipe and manufacturing method thereof
JP6642715B2 (en) High strength seamless steel pipe and riser
JP3846246B2 (en) Steel pipe manufacturing method
CN1940110A (en) Excellent weldability 490mpa low yield ratio cold shaping steel pipe and its mfg. method
WO2014156606A1 (en) High-strength steel sheet having excellent low-temperature toughness, stretchability, and weldability, and method for manufacturing same
US8685182B2 (en) High-strength steel pipe and producing method thereof
JP4336294B2 (en) Manufacturing method of high strength steel pipe for pipelines with excellent deformation characteristics after aging
JP2007262508A (en) Thick steel plate having excellent toughness in high heat input weld heat affected zone
US20120216904A1 (en) High-strength uoe steel pipe excellent in deformability and low-temperature toughness of heat affected zone
JP2002206140A (en) Steel tube and production method therefor

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