Nozzle Design: PD-5500 and AD-Merkblatter

I am student and designing a shell, head and radial nozzle in hemi head with ASME, PD 5500 and AD Merkblatter. I am using 1.25 Cr 0.5 Mo material for plate and nozzle forging. I want to take equivalent material in AD Merkblatter. Which material in AD M is equivalent to 1.25 Cr 0.5 Mo.

Also, can anybody tell me which part ( or para.) of PD 5500 and AD Merkblatter to refer for reinforcement calc. of radial nozzle in spherical head.