Deck Twin
Existing line P&ID symbol

Existing line

ISO 10628-2 (group 25) / PIP PIC001 (line conventions)
Drawn as
A screened (grey or lighter) line, sometimes labelled "EXISTING" or with a note, on brownfield drawings.
Meaning
Existing pipe that this project does not change. Model it only if the existing plant is in scope.
Variants
  • Monochrome prints may show existing lines as thin, or hatched, or with an "E" in the line number
  • Check the legend: some brownfield sets reverse this and screen the new work
No 3D component yet.