2009HG/T 20519-2009 Specification on content and procedure of detail design for chemical plant
1993HG 20519.28-1992 Flow chart; equipment and pipeline layout; pipeline axonometric drawing; pipe fitting drawing; drawing line width and font regulations of equipment installation drawing
HG 20519.28-1992 Flow chart; equipment and pipeline layout; pipeline axonometric drawing; pipe fitting drawing; drawing line width and font regulations of equipment installation drawing was changed to HG/T 20519-2009 Specification on content and procedure of detail design for chemical plant.