Cano Seamless Steel, High Strength, for Tubular Products for Petroleum deposits, and production method for Cano Seamless Steel, High Strength,For Tubular Products for Petroleum Reservoirs

摘要

A Steel Pipe, seamless, High StrengthFor Tubular Products for Oilfield which has excellent resistance to Stress Corrosion Cracking due to sulfide.The Seamless Steel Pipe, High Strength for Tubular Products for Oilfield contains: C: 0.20, 0.50% in Mass, IF: 0.05 to 0.40% by Mass, MN: 0.1 to 1.5% by Mass,Q: 0.015% by mass or less, s: 0005% by mass or less: 0.005 to 0.1% by Mass, N: 0.006% by mass or less, CR: 0.1 to 2.5% in Mass, MO: 0.1 to 1.0% by Mass, V: 0.03 0.3 Mass%, NB 0.001 0,030% by Mass, B: 0.0003 to 00030% by Mass, or: 00030 Mass% or less, and you: 0.003 to 0.025% by Mass, and satisfies the relationship you / n = 2.0 to 5.5.The Seamless Steel Pipe, High Strength, has a Tempered martensite Volume fraction of 95% or more, and a number of prior austenite Grain size of 85 or more and contains NITRIDE Inclusions which have a size of 4 mm or more and whose number is 100 or less per 100 mm2.NITRIDE Inclusions which have a size below 4 mm and whose number is 700 or less per 100 mm2.Oxide Inclusions which have a size of 4 mm or more and whose number is 60 or less per 100 mm2 and oxide Inclusions which have a size below 4 mm and whose number is 500 or lessEvery 100 mm2 in a cross-section perpendicular to the direction of Rolling.