steel pipe line nomencleature

[attaromar]

I am searching alot about the codes regulate the coding of process gas pipe lines according to rating....where I can find such codes denotes the rating with material...
e.g
AH3, B3, DL3, DW3....etc

[attaromar]

CLASS CODE- RATING- PIPING MATERIAL
A3- 150#- CARBON STEEL
AA3- 150#- CARBON STEEL
AH3- 150#- KILLED CARBON STEEL
AV3- 150#- 304 STAINLESS STEEL
B3- 300#- C.S
BH3- 300#- KILLED C.S
BV3- 300#- 304 STAINLESS STEEL
D3- 600#- C.S
DH3- 600#- KILLED C.S
DV3- 600#- 304 ST.ST.....

no LD3 mentioned, and AW3.....how could such codes been got?