Patent ID: 8865061

Claim:
A steel alloy for a low-alloy steel for producing high-strength, weldable, hot-rolled seamless steel tubing, comprising in mass-%: 0.15-0.18% C, 0.20-0.40% Si, 1.40-1.60% Mn, max. 0.05% P, max. 0.01% S, >0.50-0.90% Cr, >0.50-0.80% Mo, >0.10-0.15% V, 0.60-1.00% W, 0.0130-0.0220% N, one or more elements selected from Al, Ni, Nb, and Ti with a concentration of max. 0.03% Al, max. 0.40% Ni, max. 0.04% Nb, and max, 0.04% Ti, remainder iron with melt-related impurities, wherein a total content of added Cr, Mo and W is at least 1.6%, a ratio V/N has a value of 4 to 12 and a nickel content of the steel is not more than 0.40%.