AutoCAD P&ID comes with predefined Pipe Lines.  These are

  • Primary Line Segment
  • Secondary Line Segment
  • Primary Line Segment – Existing
  • Secondary Line Segment – Existing
  • Primary Line Segment – New
  • Secondary Line Segment – New
  • Jacketed Pipe Segment


If you want to create your own lines you can by doing the following.

Go to the properties of your project and navigate to your P&ID Class Definitions, Engineering Items and then Lines.


Right Click on Pipe Line Segments  and you will see an option to create new.  You then give it a class name as well as the Display name. (These can be different)


Select OK and it creates the new pipe


Click on Edit Line on the right hand side and it will open the Line Settings Dialog Box.10

You have the following options.

Show flow arrow – You can show whether the lines will have flow arrows on them or not

Flow Arrow style –  The flow arrow is actually a block that is found in the projSymbolStyle dwg file

Layer – This is the layer that it will be placed on

Color – you can also override the color of the line

Sline Type – You can either have a Polyline or a Mline

Linetype – You can select a linetype

Linetype scale – You can choose the linetype scale as well

Plotstyle – what color to plot

Lineweight – You choose the line weight of the pipe line

Tagging Prompt – you can automatically tag when created or prompt or not have a tag at all

Gap Priority – this is a numerical number which controls (when a line crosses another line) which line gets the gap.  The lower the number the higher the priority.  If the numbers are the same then the vertical line gets the gap

Once you are done setting up these properties you can click on OK.  You will then be able to select Add to Tool Palette and the line will be placed on the tool palette that is currently open.