C - Chemistry – Metallurgy – 22 – C
Patent
C - Chemistry, Metallurgy
22
C
C22C 38/00 (2006.01) C21D 8/10 (2006.01) C21D 9/08 (2006.01) C22C 38/12 (2006.01) C22C 38/58 (2006.01)
Patent
CA 2620054
Disclosed is a seamless steel pipe for line pipes which has high strength, good toughness and good corrosion resistance even when it is formed thick. This seamless steel pipe for line pipes has a chemical composition consisting of, in mass%, 0.02-0.08% of C, not more than 0.5% of Si, 1.5-3.0% of Mn, 0.001- 0.10% of Al, more than 0.4% and not more than 1.2% of Mo, 0.002-0.015% of N, 0.0002-0.007% of Ca, and the balance of Fe and impurities. In the impurities, P is not more than 0.03%, S is not more than 0.005%, O is not more than 0.005%, and B is less than 0.0005%. The seamless steel pipe for line pipes is also characterized in that the value of Pcm calculated by the formula (1) below is not less than 0.185 and not more than 0.250, and the seamless steel pipe has a metal structure mainly composed of bainite wherein the length of cementite is not more than 20 µm. Pcm = [C] + [Si]/30 + ([Mn] + [Cr] + [Cu])/20 + [Mo]/15 + [V]/10 + 5[B] (1) In the formula, [C], [Si], [Mn], [Cr], [Cu], [Mo], [V] and [B] represent numbers corresponding to respective contents of C, Si, Mn, Cr, Cu, Mo, V and B expressed in mass%.
L~invention concerne un tuyau d~acier sans couture pour tuyaux d~oléoduc présentant une résistance élevée, une bonne robustesse et une bonne résistance à la corrosion même s~il est épais. Ce tuyau d~acier sans couture pour tuyaux d~oléoduc a une composition chimique consistant en, en % de masse, de 0,02 à 0,08% de C, pas plus de 0,5% de Si, de 1,5 à 3,0% de Mn, de 0,001 à 0,10% d~Al, plus de 0,4% et pas plus de 1,2% de Mo, de 0,002 à 0,015% de N, de 0,0002 à 0,007% de Ca, et le reste étant constitué de Fe et d~impuretés. Parmi les impuretés, P ne dépasse pas 0,03%, S ne dépasse pas 0,005%, O ne dépasse pas 0,005%, et B est inférieur à 0,0005%. Le tuyau d~acier sans couture pour tuyaux d~oléoduc est également caractérisé en ce que la valeur de Pcm calculée par la formule (1) ci-dessous est comprise entre 0,185 et 0,250 inclus, et le tuyau d~acier sans couture a une structure métallique principalement composée de bainite où la longueur de cémentite ne dépasse pas 20 µm. Pcm = [C] + [Si]/30 + ([Mn] + [Cr] + [Cu])/20 + [Mo]/15 + [V]/10 + 5[B] (1) Dans la formule, [C], [Si], [Mn], [Cr], [Cu], [Mo], [V] et [B] représentent les nombres correspondant aux teneurs respectives de C, Si, Mn, Cr, Cu, Mo, V et B exprimées en % de masse.
Arai Yuji
Hisamune Nobuyuki
Kondo Kunio
Gowling Lafleur Henderson Llp
Sumitomo Metal Industries Ltd.
LandOfFree
Seamless steel pipe for line pipe and a process for its... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Seamless steel pipe for line pipe and a process for its..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Seamless steel pipe for line pipe and a process for its... will most certainly appreciate the feedback.
Profile ID: LFCA-PAI-O-1642043