Here's some pipes made with wave function collapse procedural generation. Press X to generate. The basic idea is random tiles are placed and used to rule out what the tiles around them can be. I found the link below helpful to understand the concept.
https://oskarstalberg.com/game/wave/wave.html
If you want to use it in your own project (although I didn't really optimize) here is the devtool I made to generate the numbers at the beginning.


Copy and paste the stuff from this into a nested array for each tile.

wfc genertation