Martensitic stainless steel seamless pipe

A martensitic stainless steel seamless pipe, consisting of, in mass %:

• C:
• 0.001 to 0.050%,
• Si:
• 0.05 to 1.00%,
• Mn:
• 0.05 to 2.00%,
• P:
• 0.030% or less,
• S:
• 0.0100% or less,
• Al:
• 0.005 to 0.100%,
• N:
• 0.020% or less,
• Ni:
• 1.00 to 9.00%,
• Cr:
• 8.00 to 16.00%,
• Cu:
• 1.15% or less,
• Mo:
• 1.00 to 5.00%,
• W:
• 0.01 to 0.25%,
• V:
• 0.010 to 1.500%,
• Co:
• 0.001 to 0.500%,
• Ca:
• 0 to 0.0250%,
• Mg:
• 0 to 0.0250%,
• B:
• 0 to 0.0200%,
• rare earth metal:
• 0 to 0.200%,
• Nb:
• 0 to 0.100%,
• Ta:
• 0 to 0.100%,
• Ti:
• 0 to 0.100%,
• Zr:
• 0 to 0.100%,
• Hf:
• 0 to 0.100%,
• Sn:
• 0 to 0.100%, and
• the balance:
• Fe and impurities,
• wherein:
• within ranges of contents of elements of the martensitic stainless steel seamless pipe, the contents of elements satisfy Formula (1), and
• a yield strength is 655 MPa or more, and a hot tensile strength of the martensitic stainless steel seamless pipe is 130 MPa or less, the hot tensile strength being a maximum stress until break when tensile stress is applied at 1100° C. after heating to 1250° C. and cooling at a cooling rate of 100° C./min:
• 10Ca+10 Mg+2B+REM≥0.0010 (1)
• where, a content in mass % of a corresponding element is substituted for Ca, Mg, and B in Formula (1), and a total content in mass % of rare earth metal is substituted for REM in Formula (1).