In order to utilize the model geometry from the CAESAR II file as an input in to CADWorx, we need to use the C2IN function.  There are some caveats to this method which are detailed below. 

1.  When importing model geometry in to CADWorx from CAESAR II, make sure that you have closed the CAESAR II model entirely.  If the world coordinate from the CAESAR II model was not changed, you can reference in the CAESAR II model directly on top of the CADWorx model, to allow easier rerouting of the new line in CADWorx.

2. Inside my CADWorx environment, I am going to import back the CAESAR II geometry that was modified during the course of analysis.  Here is the route of the line I am going to change after importing the CAESAR II model back in.

3. Prior to importing via C2IN, I created a secondary file that I could use to overlay the C2IN model geometry with.  I am using the command XREF and showing the already overlaid piping file I'll use as the XREF overlay for my production model. When I created this blank CADWorx file, I knew to go ahead and overlay the "P-200 C2IN Models" as a blank file, to utilize later.  If you do not have this file set up, create a new drawing and name it something similar.  Use the XA command back in your production model to "XREF-ATTACH" the "C2IN Models" file, so that you can view the overlay.

4. Open up your "C2IN Models" file, by either navigating to it in AutoCAD or opening it in the xref manager by right clicking the file, and choosing open.

5. In the "C2IN Models" file, you will need to be connected to a CADWorx specification in order to utilize the import command, C2IN. Additionally, pipe should be imported that only came from one CADWorx specification.  If you need to import pipe that originated from two separate specifications, then we'll need to first divide the original *.C2 file into two different files prior to the import process.  ensure that you are connected to a specification by typing in SETUP, navigating to the Specification / Size page, and very importantly: make sure you choose the spec that you want to import with the C2IN function.  Currently you cannot select the spec during C2IN function, it needs to be selected beforehand.  Press OK, or apply when you are done to close.

6. Invoke the C2IN command.  Select the file you wish to import, and then click OK.

7. If you have dynamic input turned on, you will have a list of all possible specs to recreate the file from.  Select enter at this step, as you already selected the correct spec from step 5. 

8. CADWorx rebuilds the piping components it can find from the matching specification.  If for whatever reason the piping components could not be matched, a rigid element is generated and positioned where it existed from the CAESAR II model. 

NOTE: There are multiple components that do not currently import back into the CADWorx environment.  Items like restraints in the CAESAR II model will come in as restraints in CADWorx, even if those components originated in CADWorx as 3D pipe supports.  Essentially the largest benefit of importing the model back into CADWorx is to incorporate the new line routes as an easily overlaid reference for a CADWorx designer. 

9. Save your "C2IN Models" file, and close.

10.  Open your main production model where the "C2IN Models" file was saved as a reference.  A dialog box may appear in the lower right hand corner of your AutoCAD window - click the blue button to "Reload Modified Xrefs".

11. The overlaid piping system will be referenced on top of the production model.  With this method we avoid any errors inherent in the C2IN function, but gain the benefits of viewing 3D geometry from CAESAR II.