Fixed Length Piping In Isometric Drawings

The differences on the isometric are as follows:

• All fixed length pipe items, including straight tubes, are classified as fittings, and so each one is labelled with a material list number.

• No material list numbers are plotted for flanges, because all flanges are integral parts of the purchased pipe fittings. Material list numbers appear only for gaskets and bolts at flange positions.

• Where a flange has a different pressure rating or class from the normal one for that pipeline, a message giving the actual rating is linked to the flange. Rating changes of this type will occur mainly at vessel nozzle positions or at instrument valves.