About Pipe Routing Preferences

You use routing preferences to draw accurate pipe systems in auto layout. Pipe routing preferences specify which pipe part to insert as you lay out the pipe run. Couplings are inserted at the proper pipe length and at break points in the pipe run. Routing preferences meet design standards and specifications and contain the pipe parts (pipes and fittings) used to lay out your pipe run.

Use one of these methods to search, apply, or change the pipe routing preference using the Styles Browser:
  • In the Styles Browser palette Object Type Piping Objects Pipe Part Routing Preferences
  • Select a pipe in the drawing, in the Properties palette Basic Dimensions Routing Preference click

A pipe part routing preference includes one or more size ranges for pipe parts and fittings, such as elbows, tees, laterals, and transitions. The software organizes the size ranges based on nominal pipe diameters. You can use pipe parts and fittings in a specified size range as you lay out the pipe run. The following example shows the routing preferences for Glued. Notice that the available Pipe parts are organized based on material type for US Imperial and US Metric profiles.

Routing preferences, showing parts organized based on material type

Multiple size ranges provide more flexibility in your piping designs. For example, assume a design specification for a chilled water system requires commercial steel pipe with threaded connections for all pipe sizes 3'' and lower. The system also specifies commercial steel pipe with 150 class, weld neck, flange connections for pipe sizes 3 1/2'' and higher.

When you configure a routing preference for a particular specification, the appropriate fittings are automatically inserted into the piping layout. Auto layout can generate different routing solutions, and prompts you to select the best alternative.

Pipe run drawn using a particular routing preference (Top view, Mechanical - Pipe by Size display configuration)

Pressure Pipes and Gravity Pipes

AutoCAD MEP 2023 toolset includes routing preferences for pressure pipes (horizontal or vertical piping designs) and gravity pipes (sloped piping). For example, the software inserts laterals or angled tees, when appropriate, in auto layout. The following lists a sampling of each:

Pressure pipe (US Imperial profile):

Gravity pipe (US Imperial):

Size Ranges in Routing Preferences

Pipes and fittings in a size range must have common nominal sizes in a routing preference that you can use in a pipe run. The following conditions apply to size ranges:

For example, when creating a routing preference, you select a pipe with sizes that range from 1/8” to 60” and an elbow with sizes that range from 1” to 24”. Because the lower limit of the size range is set to 1”, you can select an upper limit as high as 24”.

Note: The size ranges in the routing preference definitions in drawings created with Autodesk Building Systems 2007 were not validated by the software to ensure the selected parts had nominal sizes in common within the specified range. When you open these drawings in AutoCAD MEP 2023 toolset, they are validated. However, the validation might reset some of the upper limits to different sizes, and reset some of the parts to *NONE*.

Size range details appear on the Properties palette when you add a pipe segment to a pipe run. The nominal sizes are grouped based on the size ranges for the selected routing preference.