Patent ID: 9719615
Date: 2017-08-01
CPC Classifications: B23K,C21D,C22C,F16L

Claim:
1. A high strength steel plate for line pipe having a chemical composition containing, by mass %, C: 0.020 to 0.080%, Si: 0.01 to 0.50%, Mo: 0.01 to 0.09%, Al: 0.0005 to 0.030%, and Nb: 0.013 to 0.030% in a range of C+0.25Si+0.1Mo+Al+Nb: 0.100% or less and further containing Mn: 1.50 to 2.50%, Ti: 0.003 to 0.030%, and B: 0.0001 to 0.0030%, and limiting P: 0.020% or less, S: 0.0030% or less with a balance of Fe and unavoidable impurities.