Provided are duplex stainless seamless steel pipes with excellent low temperature toughness. The two-phase stainless seamless steel pipe according to the present disclosure has the chemical composition described in the specification and a microstructure composed of 30.0 to 70.0% ferrite and austenite. Four line segments extending in the T direction in a square observation field area having a side of 1.0 mm including the central portion of the wall thickness and including the L direction and the T direction, and dividing the observation field area into five equal parts in the L direction. A line segment is defined as a line segment T1 to T4. The four line segments extending in the L direction and dividing the observation field area into five equal parts in the T direction are defined as line segments L1 to L4. The number of intersections NT, which is the number of intersections between the line segments T1 to T4 and the ferrite interface, is 40.0 or more. The number of intersections NL, which is the number of intersections between the line segments L1 to L4 and the ferrite interface, and the number of intersections NT satisfy the equation (1). NT / NL ≧ 2.0 (1)
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机译：提供了双面不锈钢无缝钢管，具有优异的低温韧性。根据本公开的两相不锈钢无缝钢管具有本说明书中描述的化学组合物和由30.0至70.0％铁素体和奥氏体组成的微观结构。在正方形观察场区域中延伸的四个线段，其侧具有1.0mm的侧面，包括壁厚的中心部分并且包括L方向和T方向，并将观察场区域划分为五个相等的部分l方向。线段被定义为线段T1至T4。在L方向上延伸并将观察场区域划分为T方向的五个相等部分的四个线段被定义为线段L1至L4。 NT的交叉点数是线段T1至T4和铁氧体接口之间的交叉点数为40.0或更多。交叉点NL的数量，即线段L1至L4和铁氧体接口之间的交叉点数，并且交叉点NT的数量满足等式（1）。 NT / NL≧2.0（1）
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