Hello @dglus ,

If the two pipes connect without issue, then no coupling will be used. Both connectors on the pipes need to be set in a way they cannot connect to each other without a coupling coming in. 

For example, both pipes are set to a connector that has a 'male' connection. They cannot connect to each other as they are both male. When this happens, if the coupling ahs the same connectivity and is set to 'female' on both sides, it will be looked for and inserted between the two items because it is created with CID 2522.

To share the service, you can use EXPORTSYS to export a copy of what you have set up so far in the service (Importing / Exporting Services | Fabrication Products | Autodesk Knowledge Network). You can then upload the IEZ file created, and I will be able to import it, see how everything is set up, and tell you exactly what needs adjusting. 

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