| 摘要 |
PROBLEM TO BE SOLVED: To provide a steel pipe excellent in magnetic shield property.SOLUTION: A steel pipe having a composition containing, by mass%, C:0.0001 to 0.010%, Si:0.001 to 0.50%, Mn:0.01 to 0.50%, P:0.0001 to 0.05%, S:0.010% or less, Al:0.0001 to 0.01%, N:0.0001 to 0.01% and the balance Fe with inevitable impurities is applied to diameter reduction by heating at Artransformation point to 1100°C and finalizing rolling at (Artransformation point-100°C) to less than Artransformation point with diameter reduction rate of 15% or more. This provides a steel pipe excellent in magnetic shield property having a maximum relative magnetic permeability in a circumferencial direction μ:20000 or more, a saturation flux density of 1.5 tesla or more and a shield effect S (dB) under external magnetic field of 40 Gauss or more of 45 dB or more. |
