Low alloy steel for oil country tubular goods and seamless steel pipe
    1.
    发明申请
    Low alloy steel for oil country tubular goods and seamless steel pipe 审中-公开
    低合金钢用于油管和无缝钢管

    公开(公告)号:US20090098403A1

    公开(公告)日:2009-04-16

    申请号:US12232363

    申请日:2008-09-16

    摘要: A low alloy steel is provided for oil country tubular goods with a yield strength between 654 MPa and 757 MPa, and possessing excellent resistance to HIC and SSC in high-pressure hydrogen sulfides environment, and comprising, by mass %: 0.10 to 0.60% C; 0.05 to 0.5% Si; 0.05 to 3.0% Mn; 0.025% or less P; 0.010% or less S; 0.005 to 0.10% Al; 0.01% or less O (oxygen); 3.0% or less Cr; and 3.0% or less Mo, wherein the amount of Cr and Mo content is 1.2% or more, with the balance being Fe and impurities, and the number of nonmetallic inclusions whose major axis is 10 μm or more is 10 per square millimeter in the inspected cross section. The present invention provides a low alloy steel for oil country tubular goods possessing excellent resistance to sulfide stress cracking, and a seamless steel pipe.

    摘要翻译: 本发明提供一种低合金钢,其屈服强度在654MPa〜757MPa之间,在高压硫化氢环境下具有优异的抗HIC,SSC特性,其质量含量为0.10〜0.60% ; 0.05〜0.5%Si; 0.05〜3.0%Mn; 0.025%以下P; 0.010%以下S; 0.005〜0.10%Al; 0.01%以下O(氧); 3.0%以下Cr; 和3.0%以下的Mo,其中Cr和Mo的含量为1.2%以上,余量为Fe和杂质,长轴为10μm以上的非金属夹杂物的数量为10个/平方毫米 检查截面。 本发明提供一种具有优异的抗硫化物应力开裂性的油井筒用低合金钢和无缝钢管。

    Low alloy steel, seamless steel oil country tubular goods, and method for producing seamless steel pipe
    2.
    发明申请
    Low alloy steel, seamless steel oil country tubular goods, and method for producing seamless steel pipe 审中-公开
    低合金钢,无缝钢管国产管件及无缝钢管生产方法

    公开(公告)号:US20090047166A1

    公开(公告)日:2009-02-19

    申请号:US12285251

    申请日:2008-10-01

    IPC分类号: C21D9/08 C22C38/28 C22C38/32

    摘要: A low alloy steel comprising, by mass %, C: 0.10 to 0.20%, Si: 0.05 to 1.0%, Mn: 0.05 to 1.5%, Cr: 1.0 to 2.0%, Mo: 0.05 to 2.0%, Al: 0.10 % or less and Ti: 0.002 to 0.05%, and with a Ceq value obtained by the following formula (1) of 0.65 or more, with the balance being Fe and impurities, wherein in the impurities, P is 0.025% or less, S is 0.010% or less, N is 0.007% or less, and B is less than 0.0003%, and the number per unit area of M23C6 type precipitates (M: a metal element) whose grain diameter is 1 μm or more is 0.1/mm2 or less. This invention provides a low alloy steel possessing both hardenability and toughness and improves the resistance to sulfide stress corrosion cracking. Ceq=C+(Mn/6)+(Cr+Mo+V)/5   formula (1) where C, Mn, Cr, Mo and V in the formula (1) denote the mass % of respective elements.

    摘要翻译: 1.一种低合金钢,以质量%计含有C:0.10〜0.20%,Si:0.05〜1.0%,Mn:0.05〜1.5%,Cr:1.0〜2.0%,Mo:0.05〜2.0%,Al:0.10% 较小,Ti:0.002〜0.05%,下述通式(1)所得的Ceq值为0.65以上,余量为Fe和杂质,其中,在杂质中,P为0.025%以下,S为0.010 %以下,N为0.007%以下,B小于0.0003%,粒径为1μm以上的M23C6型析出物(M:金属元素)的单位面积数为0.1个/ mm 2以下 。 本发明提供了具有淬透性和韧性两者的低合金钢,提高了耐硫化应力腐蚀开裂性。 Ce = C +(Mn / 6)+(Cr + Mo + V)/ 5式(1)<?in-line-formula description =“In-line formula”end =“lead” 式中,式(1)中的C,Mn,Cr,Mo和V表示各元素的质量%。