How to add coupling to pipe?
Hello,
You must have a pipe fitting which part type is transition, and set it to the routing preferences in the type properties.
Also this transition component should work according to the pipe sizes on both ends.
If it is not clear I can explain better later.
Fábio Sato
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Accepted solution
Hi @Anonymous,
Welcome to the community! 
Did you manage to resolve your issue? Did Fabio's input help you?
Below is an image to explain the workflow:
1. Select a Pipe Segment
2. Click on Edit Type
3. Click on "Edit" Routing Preferences
4. Add a Transition Fitting, either to all pipe sizes
OR
5. Add another Transition Type Fitting with specific sizes (Last image).
Last Image, additional Transitions with Specific Sizes associated.
I hope this helps! 