2009HG/T 20519-2009 Specification on content and procedure of detail design for chemical plant
1993HG 20519.14-1992 Pipe Isometric Drawing Index and Segment Table Index
HG 20519.14-1992 Pipe Isometric Drawing Index and Segment Table Index was changed to HG/T 20519-2009 Specification on content and procedure of detail design for chemical plant.