CSN 42 0284-1969 Instructions for treatment of carbon steel grades 11, 12 and casting of carbon steel grade 26 for constructions of steam boilers and other pressure vessels and steam pipings
1969CSN 42 0284-1969 Instructions for treatment of carbon steel grades 11, 12 and casting of carbon steel grade 26 for constructions of steam boilers and other pressure vessels and steam pipings