HIGH-STRENGTH THICK-WALLED ELECTRIC-RESISTANCE-WELDED STEEL PIPE HAVING EXCELLENT LOW-TEMPERATURE TOUGHNESS, AND METHOD FOR MANUFACTURING SAME
    7.
    发明公开
    HIGH-STRENGTH THICK-WALLED ELECTRIC-RESISTANCE-WELDED STEEL PIPE HAVING EXCELLENT LOW-TEMPERATURE TOUGHNESS, AND METHOD FOR MANUFACTURING SAME 审中-公开
    高钢的强度和管性优异厚壁WIDERSTANDSGESCHWEISSTES其制造冷韧性和方法

    公开(公告)号:EP2837708A1

    公开(公告)日:2015-02-18

    申请号:EP13775345.5

    申请日:2013-04-11

    摘要: There is provided a high-strength thick-walled electric resistance welded steel pipe having excellent low-temperature toughness and excellent HIC resistance and having a yield strength of 400 MPa or more.
    Steel is heated to and held at a temperature in the range of 1200°C to 1280°C. The steel has a chemical composition consisting of C: 0.025% to 0.084%, Si: 0.10% to 0.30%, Mn: 0.70% to 1.80%, controlled amounts of P, S, Al, N, and O, Nb: 0.001% to 0.065%, V: 0.001% to 0.065%, Ti: 0.001% to 0.033%, and Ca: 0.0001% to 0.0035% on a mass percent basis and the remainder being Fe and incidental impurities, and satisfies Pcm of 0.20 or less. The steel is hot-rolled at a rolling reduction of 20% or more in an unrecrystallization temperature range. After the completion of the hot-rolling, the steel is cooled to a finish cooling temperature of 630°C or less at a cooling rate in the range of 7°C/s to 49°C/s and is coiled at 400°C or more and less than 600°C to form a hot-rolled steel strip. The hot-rolled steel strip is subjected to roll-forming and electric resistance welding to produce an electric resistance welded steel pipe. The welded portion of the electric resistance welded steel pipe is then subjected to a heat treatment in which the welded portion is heated to a temperature in the range of 800°C to 1150°C over the total wall thickness and is then cooled to 630°C or less at an average cooling rate in the range of 7°C/s to 49°C/s. The base steel portion and the electric resistance welded portion of the resulting high-strength thick-walled electric resistance welded steel pipe have excellent low-temperature toughness and excellent HIC resistance.

    摘要翻译: 本发明提供一种高强度厚壁电阻焊钢管具有优异的低温韧性和优良的耐HIC性,并且具有400MPa以上的屈服强度的管道。 钢被加热到并在1200℃范围内的温度为1280℃下保持 该钢的化学组成自由C:0.025%至0.084%以下,Si:0.10%〜0.30%至以下,Mn:0.70%〜1.80%,P,S,铝,N,和O,Nb的受控量:0.001% 到0.065%,V:0.001%至0.065%以下,Ti:0.001%〜0.033%,及Ca:以质量%计,其余为的零时20分以下的Fe和不可避免的杂质,和SATIS外资企业的Pcm上0.0001%〜0.0035%。 钢进行热轧,在未再结晶在温度范围内的压下率的20%或更多英寸 热轧结束后,将钢中的7℃/ s的范围内的冷却速度冷却到630℃或更低的瓶口冷却温度至49℃/秒和在400℃下进行卷取 以上且小于600℃,以形成热轧钢带。 的热轧钢带进行辊轧成形和电阻焊接,以产生对电阻焊钢管。 电阻焊钢管的焊接部分然后进行热处理,其中所述焊接部被加热至800℃的范围内,以1150℃以上的总壁厚的温度,然后冷却至630℃ C.或在7℃/ s的范围内,以49℃/ s的平均冷却速度以下。 基体钢部分和所得到的高强度厚壁电阻焊钢管的电阻焊接部具有优异的低温韧性和优良的耐HIC性。

    CENTRIFUGALLY CAST COMPOSITE ROLLING MILL ROLL AND MANUFACTURING METHOD THEREFOR
    10.
    发明公开
    CENTRIFUGALLY CAST COMPOSITE ROLLING MILL ROLL AND MANUFACTURING METHOD THEREFOR 有权
    ZENTRIFUGAL GEGOSSENE ZUSAMMUSTRETZTE W​​ALZWERKWALZE UND HERSTELLUNGSVERFAHRENDAFÜR

    公开(公告)号:EP2706128A1

    公开(公告)日:2014-03-12

    申请号:EP12851017.9

    申请日:2012-11-21

    IPC分类号: C22C37/00 B21B27/00 B22D13/02

    摘要: A centrifugally cast composite roll comprising an outer layer made of cast iron having a chemical composition comprising, by mass, 2.7-3.5% of C, 1.5-2.5% of Si, 0.4-1.0% of Mn, 3.7-5.1% of Ni, 0.8-2.2% of Cr, 1.5-4.5% of Mo, 2.0-4.5% of V, and 0.5-2.0% of Nb, the balance being Fe and inevitable impurities, a mass ratio of Nb/V being 0.18-0.65, and a mass ratio of Mo/V being 0.7-2.5, and a structure comprising, by area, 15-45% of a cementite phase and 1-10% of a graphite phase, and an inner layer made of cast iron having excellent mechanical strength and metallurgically bonded to the outer layer; a usable region of the outer layer as deep as 10 mm or more from the surface containing substantially no speck-like-segregated dendrites of bainite and/or martensite having diameters of 1.5 mm or more.

    摘要翻译: 一种离心铸造复合辊,包括由铸铁制成的外层,其具有以质量计包含C:2.7-3.5%,Si:1.5-2.5%,Mn:0.4-1.0%,Ni:3.7-5.1% Cr的0.8-2.2%,钼的1.5-4.5%,V的2.0-4.5%以及Nb的0.5〜2.0%,余量为Fe和不可避免的杂质,Nb / V的质量比为0.18〜0.65, Mo / V的质量比为0.7-2.5,并且包括面积为15-45%的渗碳体相和1-10%石墨相的结构,以及由铸铁制成的具有优异的机械强度的内层 并与外层冶金结合; 从基本上不含有直径为1.5mm以上的贝氏体和/或马氏体的斑点状分离的树突的表面,外层的可用区域为10mm以上。