公开(公告)号：EP2796587A1

公开(公告)日：2014-10-29

申请号：EP12859680.6

申请日：2012-12-18

申请人： JFE Steel Corporation

发明人： EGUCHI, Kenichiro ,  ISHIGURO, Yasuhide ,  MIYATA, Yukio

IPC分类号： C22C38/32 ,  C22C38/54 ,  C21D8/10 ,  C21D9/08

CPC分类号： C21D8/105 ,  C21D1/25 ,  C21D8/10 ,  C21D9/08 ,  C21D9/085 ,  C21D2211/008 ,  C21D2221/02 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/20 ,  C22C38/22 ,  C22C38/24 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/54 ,  F16L9/02

摘要： A seamless steel pipe has a composition containing, by mass%, C: 0.15 to 0.50%, Si: 0.1 to 1.0%, Mn: 0.3 to 1.0%, P: 0.015% or less, S: 0.005% or less, Al: 0.01 to 0.1%, N: 0.01% or less, Cr: 0.1 to 1.7%, Mo: 0.40 to 1.1%, V: 0.01 to 0.12%, Nb: 0.01 to 0.08%, Ti: 0.03% or less, and B: 0.0005 to 0.003%, has a structure composed of a tempered martensite phase as a main phase with a prior austenite grain size number of 8.5 or more, and has a hardness distribution in which in four portions 90° apart from each other in the circumferential direction, hardness is 295 HV10 or less in any one of an inner surface-side region at 2.54 to 3.81 mm from the inner surface of the pipe, an outer surface side-region at the same distance from the outer surface of the pipe, and a center of the thickness. Therefore, the seamless steel pipe has high strength of 110 ksi grade (yield strength: 758 MPa or more) and excellent SSC-resistance. The composition may further contain Cu and/or W and/or Ni and/or Ca.

摘要翻译： 甲无缝钢管具有如下组成成分：以质量％计含有C：0.15〜12：50％以下，Si：0.1〜1.0％以下，Mn：0.3〜1.0％，P：0.015％以下，S：0.005％或以下，Al： 0点01分〜0.1％，N：0.01％以下，Cr：0.1〜1.7％以下，Mo：0.40〜1.1％，V：0.01〜12：12％以下，Nb：0.01〜12：08％以下，Ti：0.03％以下，B： 0.0005〜0.003％，具有与8.5或更高的原始奥氏体粒度号为主相的回火马氏体相构成的结构，并且具有在四个部分90°彼此分开在圆周方向上，其中A硬度分布 ，硬度是在其内表面侧的区域中的任何一个在2:54从管的内表面在与管的外表面相同的距离295 HV10或更少3.81毫米，外表面侧区域，和一个 厚度的中心。 因此，无缝钢管具有110ksi级的高强度（屈服强度：758 MPa以上）和优良的耐SSC性。 该组合物可以含有另外的Cu和/或W和/或Ni和/或Ca.

公开(公告)号：EP2562284A1

公开(公告)日：2013-02-27

申请号：EP11772096.1

申请日：2011-04-15

申请人： JFE Steel Corporation

发明人： MIYATA, Yukio ,  KIMURA, Mitsuo

IPC分类号： C22C38/00 ,  C22C38/58

摘要： Provided is a Cr-containing steel pipe for linepipe having X-65 to X-80 class high strength and being excellent in toughness, corrosion resistance and resistance to sulfide stress corrosion cracking, and also being excellent in resistance to intergranular stress corrosion cracking in a welded heat affected zone. To be more specific, the composition of the Cr-containing steel pipe contains, by mass% 0.001 to 0.015% C, 0.05 to 0.50% Si, 0.10 to 2.0% Mn, 0.001 to 0.10% Al, 15.0 to 18.0% Cr, 2.0 to 6.0% Ni, 1.5 to 3.5% Mo, 0.001 to 0.20% V, and 0.015% or less N so as to satisfy the following relationship of Cr + Mo + 0.4W + 0.3Si - 43.5C - 0.4Mn - Ni - 0.3Cu- 9N: 11.5 to 13.3. A welded heat affected zone which is heated to a ferrite single phase temperature region of 1300°C or more at the time of welding and is cooled has the microstructure where 50% or more of prior-ferrite grain boundaries is occupied by a martensite phase and/or an austenite phase in a ratio to the whole length of the prior-ferrite grain boundaries. Accordingly, the formation of a Cr carbide depleted zone is suppressed thus providing a steel pipe which remarkably enhances resistance to intergranular stress corrosion cracking in a welded heat affected zone. Due to such a steel pipe, it is possible to acquire an advantageous effect that it becomes unnecessary to perform post weld heat treatment thus remarkably shortenning a construction period of the welded steel pipe structure.

摘要翻译： 提供了一种用于具有线管X-65至X-80级的高强度和韧性，耐腐蚀性和耐优异硫化物应力腐蚀开裂，因此，在晶间应力腐蚀性优良在裂化含Cr钢管 焊接热影响部。 更具体地，含Cr钢管的组合物含有以质量％计0.001〜0.015％的C，12:05至00：50％的Si，0:10〜2.0％的Mn，0.001〜0.10％于Al，15.0〜18.0％的Cr，2.0 至6.0％的Ni，1.5〜3.5％的Mo，0.001〜0.20％，V，和0.015％或更低的N，以便满足的Cr +沫+ 0.4W + 0.3Si的以下关系 - 43.5C - 0.4Mn - 镍 - 0.3 铜9N：11.5〜13.3。 焊接热影响区的所有被加热到1300℃或更高的铁素体单相的温度区域在焊接时和冷却具有这样的现有的铁素体晶界的50％或更多是由马氏体相所占的微观结构和 /或在一个比现有铁氧体晶粒边界的整个长度奥氏体相。 因此，Cr碳化物贫化区的形成被抑制，从而提供一个钢管哪个显着地提高到粒间应力腐蚀焊接热影响区裂纹性。 由于寻求钢管，能够获得在有利效果做了它变得不必要，从而执行焊接后热处理显着shortenning焊接钢管结构的施工工期。

公开(公告)号：EP2857530B1

公开(公告)日：2018-12-12

申请号：EP13796392.2

申请日：2013-05-30

申请人： JFE Steel Corporation

发明人： MIYATA, Yukio ,  ISHIGURO, Yasuhide ,  ISHIKAWA, Kazutoshi ,  NAKAHASHI, Tetsu

IPC分类号： C21D8/10 ,  C21D9/08 ,  C22C38/00 ,  C22C38/58

CPC分类号： C22C38/54 ,  C21D8/10 ,  C21D8/105 ,  C21D9/08 ,  C21D9/085 ,  C21D2211/001 ,  C21D2211/005 ,  C21D2211/008 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50

摘要： Provided is a high-strength stainless steel tube for oil country tubular goods having a wall thickness of more than 25.4 mm and a high strength of a 110 ksi (758 MPa) grade yield stress or more with excellent toughness and excellent corrosion resistance. A steel material having a chemical composition containing, by mass%, C: 0.005% or more and 0.06% or less, Si: 0.05% or more and 0.5% or less, Mn: 0.2% or more and 1.8% or less, Cr: 15.5% or more and 18.0% or less, Ni: 1.5% or more and 5.0% or less, V: 0.02% or more and 0.2% or less, Al: 0.002% or more and 0.05% or less, N: 0.01% or more and 0.15% or less, O: 0.006% or less, and further containing one or more of Mo: 1.0% or more and 3.5% or less, W: 3.0% or less and Cu: 3.5% or less, in which the relational expressions Cr+0.65Ni+0.60Mo+0.30W+0.55Cu-20C‰¥19.5 and Cr+Mo+0.50W+0.30Si-43.5C-0.4Mn-Ni-0.3Cu-9N‰¥11.5 are satisfied, is made into a seamless steel tube by performing heating and hot rolling. The hot rolling is performed under conditions such that the total rolling reduction in a temperature range of 1100°C to 900°C is 30% or more. After the hot rolling has been performed, cooling is performed at a cooling rate equal to or more than an air-cooling rate, and, further, quenching-tempering is performed. With this method, a high-strength and high-toughness seamless steel tube having a strength of 110 ksi (758 MPa) or more and a toughness of 40 J or more in terms of vE- 10 despite having a thick wall and excellent corrosion resistance even in a high-temperature corrosion environment having a temperature of 230°C and containing CO 2 and Cl - can be stably manufactured.

公开(公告)号：EP1717328B1

公开(公告)日：2018-09-12

申请号：EP04801614.1

申请日：2004-12-01

申请人： JFE Steel Corporation

发明人： MIYATA, Yukio ,  KIMURA, Mitsuo ,  ITAKURA, Noritsugu ,  MASAMURA, Katsumi

IPC分类号： C22C38/06 ,  C22C38/40 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  C22C38/02 ,  C22C38/04 ,  C22C38/44 ,  C21D6/00 ,  C21D9/14 ,  C21D1/25 ,  C22C38/00

CPC分类号： C22C38/44 ,  C21D1/25 ,  C21D6/004 ,  C21D9/14 ,  C22C38/002 ,  C22C38/004 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/40 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50 ,  Y10T428/13

摘要： A martensitic stainless steel pipe having a heat-affected zone with high resistance to intergranular stress corrosion cracking is provided. In particular, the martensitic stainless steel pipe contains less than 0.0100% of C; less than 0.0100% of N; 10% to 14% of Cr; and 3% to 8% of Ni on a mass basis. Alternatively, the martensitic stainless steel pipe may further contain Si, Mn, P, S, and Al within an appropriate content range. The martensitic stainless steel pipe may further contain one or more selected from the group consisting of 4% or less of Cu, 4% or less of Co, 4% or less of Mo, and 4% or less of W and one or more selected from the group consisting of 0.15% or less of Ti, 0.10% or less of Nb, 0.10% or less of V, 0.10% or less of Zr, 0.20% or less of Hf, and 0.20% or less of Ta on a mass basis. The content C sol defined by the following equation is equal to less than 0.0050%: C sol = C - 1/3 × C pre , wherein C pre = 12.0 {Ti/47.9 + 1/2 (Nb/92.9 + Zr/91.2) + 1/3 (V/50.9 + Hf/178.5 + Ta/180.9) - N/14.0} or C pre = 0 when C pre

公开(公告)号：EP2865777A1

公开(公告)日：2015-04-29

申请号：EP13807143.6

申请日：2013-06-19

申请人： JFE Steel Corporation

发明人： EGUCHI, Kenichiro ,  ISHIGURO, Yasuhide ,  MIYATA, Yukio ,  KIMURA, Mitsuo

IPC分类号： C22C38/00 ,  C21D9/08 ,  C22C38/46 ,  C22C38/54

CPC分类号： C22C38/54 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C21D9/08 ,  C21D9/085 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/005 ,  C22C38/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50

摘要： Chemical composition contains, by mass%, C: 0.05% or less, Si: 0.5% or less, Mn: 0.15% or more and 1.0% or less, Cr: 13.5% or more and 15.4% or less, Ni: 3.5% or more and 6.0% or less, Mo: 1.5% or more and 5.0% or less, Cu: 3.5% or less, W: 2.5% or less, and N: 0.15% or less so that the relationship -5.9 x (7.82 + 27C - 0.91Si + 0.21Mn - 0.9Cr + Ni - 1.1Mo - 0.55W + 0.2Cu + 11N) ≥ 13.0 is satisfied. By this method, it is possible to manufacture a high strength stainless steel seamless pipe having excellent resistance to sulfide stress cracking equivalent to that of a steel having a chemical composition containing about 17% of Cr even with a chemical composition having comparatively low Cr content of about 15 mass%. In addition, V: 0.02% or more and 0.12% or less and/or Al: 0.10% or less and/or one or more selected from among Nb: 0.02% or more and 0.50% or less, Ti: 0.02% or more and 0.16% or less, Zr: 0.50% or less, and B: 0.0030% or less and/or one or more selected from among REM: 0.005% or less, Ca: 0.005% or less, and Sn: 0.20% or less may be further contained.

摘要翻译： 化学组合物中含有以质量％计，C：0.05％以下，Si：0.5％以下，Mn：0.15％以上且1.0％以下，Cr：13.5％以上且15.4％以下，Ni：3.5％ 以上且6.0％以下，Mo：1.5％以上且5.0％以下，Cu：3.5％以下，W：2.5％以下，和N：0.15％以下所以没有关系-5.9 X（7.82 + 27℃ - + 0.91Si 0.21Mn - 0.9Cr +镍 - 1.1Mo - 0.55W + 0.2Cu + 11N）‰¥13.0成立。 通过该方法，能够制造具有优异的耐硫化物应力开裂相当于做了钢的具有如下化学成分含铬约17％，即使具有相对低的Cr含量的化学组成的高强度不锈钢无缝管 约15％（质量）。 此外，V：0.02％以上且0.12％，或更小和/或Al：0.10％以下和/或一种或选自Nb中多个选定：0.02％以上且0.50％以下，Ti：0.02％以上 和12：16％或以下，Zr：0.50％以下，以及B：0.0030％以下和/或一个或多个选自REM中选择的：0.005％以下，Ca：0.005％以下，及Sn：0.20％，或更小 可以进一步含有。

公开(公告)号：EP2172573B1

公开(公告)日：2014-12-10

申请号：EP07829943.5

申请日：2007-10-10

申请人： JFE Steel Corporation

发明人： MIYATA, Yukio ,  KIMURA, Mitsuo ,  TANAKA, Masahito ,  SHIMAMOTO, Ken

IPC分类号： C22C38/00 ,  B21D3/00 ,  C21D9/08 ,  C22C38/58 ,  C22C38/02 ,  C22C38/40 ,  C22C38/04 ,  C21D6/00 ,  C21D9/14 ,  C21D1/22 ,  C21D8/10

CPC分类号： C21D9/14 ,  C21D1/22 ,  C21D6/004 ,  C21D8/105 ,  C21D9/08 ,  C21D2211/008 ,  C22C38/004 ,  C22C38/02 ,  C22C38/04 ,  C22C38/40 ,  C22C38/58

公开(公告)号：EP2322679A1

公开(公告)日：2011-05-18

申请号：EP08876878.3

申请日：2008-12-24

申请人： JFE Steel Corporation

发明人： EGUCHI, Kenichiro ,  MIYATA, Yukio ,  KIMURA, Mitsuo

IPC分类号： C22C38/00 ,  C22C38/48 ,  C22C38/58

CPC分类号： C22C38/26 ,  C22C38/001 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/48

摘要： A seamless steel tube for OCTG which possesses both of high strength of yield strength YS of 95 ksi grade (665 to 758 MPa) and excellent low-temperature toughness, and a manufacturing method of the seamless steel tube are provided. To be more specific, to a stainless steel seamless tube having the composition which contains, by mass%, 0.020% or less C, 10 to 14% Cr, 3% or less Ni, 0.05% or less N, 0.03 to 0.2% Nb, and optionally further, 1.0% or less Si, 0.1 to 2.0% Mn, 0.020% or less P, 0.010% or less S, 0.10% or less Al, and Fe and unavoidable impurities as a balance, quenching in which the seamless tube is heated at a quenching temperature of A c3 transformation temperature or above and, thereafter, the seamless tube is cooled to a temperature range of 100°C or less at a cooling rate of air cooling or more, and tempering which follows the quenching and in which the seamless tube is heated at a tempering temperature of 550°C or above and is cooled are applied. Due to such treatment, a martensitic stainless steel seamless tube for country tubular goods which has the tempered martensitic structure where a precipitated Nb quantity is 0.020% or more, and possesses both of high strength at yield strength of 95 ksi grade and the excellent low-temperature toughness of fracture transition temperature vTrs of -40°C or below, and allows the hot straightening. In addition to the above-mentioned composition, the seamless steel tube may further contain one or two kinds of elements selected from Cu, Mo and/or one or two kinds selected from V, Ti, B in addition to the above-mentioned composition.

摘要翻译： 提供了用于OCTG的无缝钢管其具有两个高强度的为95ksi级（665至758兆帕）和优良的低温韧性，以及无缝钢管的制造方法的屈服强度YS的。 更具体地，涉及一种具有其中包含，以质量％计的组合物，0.020％或更少的C，10〜14％的Cr，3％或更少的Ni，0.05％以下N不锈钢无缝管; 0.03〜0.2％的Nb ，并任选地进一步，1.0％或更少的Si，0.1〜2.0％的Mn，0.020％或更少的P，0.010％或更少的S，0.10％或更少的Al，和Fe及不可避免的杂质作为余量，淬火其中无缝管 在Ac 3转变温度的以上和淬火温度下加热，此后，无缝管在空气冷却或更多，和回火的冷却速度跟随在淬火和冷却至温度范围为100℃或更低 其中无缝管在550℃的回火温度以上加热和冷却应用。 由于寻求治疗，对于国家管用马氏体系不锈钢无缝钢管其具有回火马氏体结构，其中一个析出Nb量为0.020％以上，并且具有两个高强度在95千磅级屈服强度和优良的低 为-40℃或更低断裂转变临界温度vTrs的低温韧性，并允许该热矫直。 除了上述组合物中，无缝钢管还可以含有选自Cu，Mo和/或除了上述组合物从钒，钛，B中选择一种或两种选择的元素的一种或两种。

公开(公告)号：EP3228413B1

公开(公告)日：2019-04-17

申请号：EP15866042.3

申请日：2015-12-01

申请人： JFE Steel Corporation

发明人： SUZUKI, Takeshi ,  MIYATA, Yukio ,  OTA, Hiroki ,  IDE, Shinsuke

IPC分类号： B23K35/30 ,  B23K9/23 ,  B23K31/00 ,  B23K9/028 ,  C22C38/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/50 ,  C22C38/58 ,  C21D6/00 ,  C21D9/08 ,  B23K101/06 ,  B23K103/04

公开(公告)号：EP3228413A1

公开(公告)日：2017-10-11

申请号：EP15866042.3

申请日：2015-12-01

申请人： JFE Steel Corporation

发明人： SUZUKI, Takeshi ,  MIYATA, Yukio ,  OTA, Hiroki ,  IDE, Shinsuke

IPC分类号： B23K9/23 ,  B23K31/00 ,  B23K35/30 ,  C22C38/00 ,  C22C38/40 ,  C22C38/58

CPC分类号： B23K9/23 ,  B23K9/0282 ,  B23K31/00 ,  B23K35/30 ,  B23K35/3086 ,  B23K2101/06 ,  B23K2103/05 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C21D9/08 ,  C21D2211/008 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/004 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/40 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/50 ,  C22C38/58

摘要： Provided is a method for producing a circumferential weld joint including a weld metal having high strength, high toughness, and high corrosion resistance. With this method, when low-carbon martensitic stainless steel pipes used for pipelines for transportation of petroleum and natural gas are subjected to circumferential welding, the circumferential welding can be performed efficiently using a low-cost welding material having a composition similar to the composition of the low-carbon martensitic stainless steel pipes.
Pipe ends of low-carbon martensitic stainless steel pipes containing prescribed components are butted against each other and subjected to multi-pass arc welding using a welding material containing prescribed components. In the first pass in the multi-pass arc welding, CMT welding is performed in which the welding material is moved back and forth against a molten pool to generate an arc intermittently. In the second and subsequent passes, one selected from GMA welding, GTA welding, and the CMT welding is performed.

摘要翻译： 本发明提供一种用于制造具有高强度，高韧性和高耐腐蚀性的焊接金属的周向焊接接头的方法。 根据该方法，在对石油和天然气的输送用管路所使用的低碳马氏体系不锈钢管进行周方向焊接的情况下，能够使用具有与组成类似的低成本焊接材料 低碳马氏体不锈钢管。 含有规定成分的低碳马氏体系不锈钢管的管端彼此对接，并使用含有规定成分的焊接材料进行多次电弧焊接。 在多道次电弧焊接的第一道次中，执行CMT焊接，其中焊接材料相对于熔池来回移动以间歇地产生电弧。 在第二次及以后的过程中，执行从GMA焊接，GTA焊接和CMT焊接中选​​择的一个。

公开(公告)号：EP2843068A1

公开(公告)日：2015-03-04

申请号：EP12875045.2

申请日：2012-04-26

申请人： JFE Steel Corporation

发明人： MIYATA, Yukio ,  KIMURA, Mitsuo

IPC分类号： C22C38/00 ,  C22C38/58

CPC分类号： C22C38/58 ,  C21D6/004 ,  C21D8/0226 ,  C21D8/0263 ,  C21D9/50 ,  C22C38/001 ,  C22C38/002 ,  C22C38/004 ,  C22C38/005 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C22C38/50

摘要： A Cr containing steel pipe for linepipe having high strength of X65 to X80 grade excellent in toughness, corrosion resistance, resistance to sulfide stress cracking and resistance to IGSCC in a welded heat affected zone is provided. Specifically, the steel pipe has a chemical composition consisting of, by mass%, C: 0.001% to 0.015%, Si: 0.05% to 0.50%, Mn: 0.10% to 2.0%, Al: 0.001% to 0.10%, Cr: 13% or more and less than 15%, Ni: 2.0% to 5.0%, Mo: 1.5% to 3.5%, V: 0.001% to 0.20%, N: 0.015% or less, and the balance being Fe and inevitable impurities, under the condition that P 1 is 11.5 to 13.3 and that P 2 =(0.5Cr+5.0)-P 1 is 0 or more. With this chemical composition, since a microstructure in a welded heat affected zone, which is subjected to heating up to a temperature range for forming ferrite single phase of 1300°C or higher and to cooling when welding is performed, is formed such that 50% or more of prior-ferrite grain boundaries, in a ratio with respect to the total length of the prior-ferrite grain boundaries, is occupied by martensite phase, and since formation of Cr carbide depleted zones is suppressed, a pipe having significantly increased resistance to IGSCC in a welded heat affected zone can be obtained. Since it is not necessary to perform a post weld treatment, there is a merit of significantly decreasing construction period of welded steel pipe structures.

摘要翻译： 的含Cr钢管具有X65的高强​​度干线用管到X80级优异的韧性，耐腐蚀性，耐硫化物应力开裂性和耐IGSCC在焊接热影响区处。 具体而言，钢管的化学组成由...组成，以质量％计，C：0.001％〜0.015％以下，Si：0.05％至12：50％以下，Mn：0.10％至2.0％以下，Al：0.001％〜0.10％以下，Cr： 13％以上且小于15％以下，Ni：2.0％至5.0％以下，Mo：1.5％〜3.5％，V：0.001％至0.20％，N：0.015％或以下，余量为Fe和不可避免的杂质， 的条件下做了P 1为5.11至3.13，做P 2 =（0.5Cr + 5.0）-P 1为0以上。 与此化学组成中，由于在焊接热影响区中的微观结构，所有这一切进行加热的温度范围形成的1300℃以上的铁素体单相，并冷却在焊接进行时，形成的搜索没有50％ 或多个先前铁素体晶界的，在相对于所述现有的铁素体晶界的总长度之比，是由马氏体相占据，并且由于形成Cr碳化物贫化区被抑制，管具有显着增加至电阻 IGSCC在焊接热影响部可制得。 因为这是没有必要进行焊接后处理，有显着降低焊接钢管结构的施工工期的优点。