You can use assemblies in routing to represent equipment or special routing assemble components, such as valves or strainers.
If they represent routing components, they must include Assembly Connection Points (ACP) and Assembly Route Points (ARP). These correlate to connection points and route points.
You can create equipment that is connected to a route in an assembly or part form. However, you should make allowances for connecting to the route. For example, with piping, you might use a flange to connect the pipe route to a combination of pump, strainer and valve equipment.
Assembly fittings can be used as route fittings within the route assembly only. You can not create a new route assembly within an assembly fitting.