To modify a joint type

In the Setup tree view, expand Plant 3D DWG Settings. Click Configure Piping Connection Settings.
In the Simple Joints list, click a joint type (for example: Buttweld).
Click Modify.
In the Modify Joint dialog box, click Add Property.
In the Select Class Property dialog box, click a Property (for example: Port Pressure Class).
Click OK.
In the Modify Joint dialog box, click Modify.
Note:
If you add pressure class match to a buttweld joint, pipe and fittings must be the same pressure class to connect. Existing buttweld joints are not modified.