What are the standards of the classification societies for ship pipes?

Ship pipes (GB/T5312-85) are carbon steel seamless pipes used to build Class I pressure piping systems, Class II pressure piping systems, boilers and superheaters. The working temperature of the carbon steel seamless pipe wall does not exceed 450℃, and the working temperature of the alloy steel seamless pipe wall exceeds 450℃.
GB/T5312-1999 (Carbon steel and carbon-manganese steel seamless steel tubes for ships). Mainly used for I and II pressure pipes for marine boilers and superheaters. Representative materials are 360, 410, 460 steel grades, etc.
The calculation formula of steel pipe weight: [(outer diameter-wall thickness)*wall thickness]*0.02466=kg/m (weight per meter).

Standard
China Classification Society Material and Welding Rules — China Classification Society (CCS)
Det Norske Veritas (DNV) Specification — Det Norske Veritas (DNV)
Lloyd's Register of Shipping (LR) specifications — Lloyd's Register of Shipping (LR)
German Lloyd's Register of Shipping (GL) specifications — German Lloyd's Register of Shipping (GL)
American Bureau of Shipping (ABS) specifications — American Bureau of Shipping (ABS)
Bureau Veritas (BV) specifications — Bureau Veritas (BV)
Rules of the Italian Register of Shipping (RINA) — Italian Register of Shipping (RINA)
Japan Classification Society (NK) specification — Japan Classification Society (NK)
GB/T5312 — China National Standard