X22CrMoV12-1 or 1.4923
C: 0.18%-0.24% Si: 0.50% max Mn: 0.40%-0.90% P: 0.025% max S: 0.015% max Cr: 11.0%-12.5% Mo: 0.80%-1.20% Ni: 0.30%-0.80% V: 0.25%-0.35%