Hello from a brand new member. Before my questions, I have to make some premises, in order to be better understood. As we ALL know, since the new 2011 CODEWARE COMPRESS 7110 release, it is now possible to export the solid models properly created and designed according to the ASME code in the COMPRESS environment to any (or at least to most common) CAD environments, including of course INVENTOR 2011. COMPRESS allows the designer to export the solid model in the following file formats:.step.iges.g.jt.sat.3dxml What is the purpose of exporting the solid model of -as example- a pressure vessel from COMPRESS to INVENTOR? Well, the answer to this is quite intuitive: once the model is properly exported into the INVENTOR environment, then all the advantages of having a proper well structured INVENTOR model come in sequence, first of all the possibility of creating each flat pattern for any rolled surface such as the shell, pads, nozzles existing in the designed vessel. And here comes the whole point: Is it actually possible to perform this operation? Is it possible from a rolled shell properly imported from COMPRESS to INVENTOR to 'flatten' it, and therefore derive normal.dwg drawings to be forwarded to the shop? Here's what I did, and the hurdles that I experienced. I exported the COMPRESS solid model in each one of the forementioned file formats. Found 7 results for Codeware Compress Build 6258. Full version downloads available, all hosted on high speed servers! Now I will focus on the.step file format, called VESSEL.step, but It seems to me (I might be wrong) that the behaviour and the characteristics off all the different file formats are pretty much the same, as in each case one or more main assemblies (.iam) files are created, and also are created all the part files (.ipt), depending of the actual vessel's components. 2. I opened the previously exported VESSEL.step file, and in doing so I had to select from different options in the create surface as OPEN dialog box: - Individual Surface Bodies - Single Composite Feature - Multiple Composite Feature - Single Construcion Group - Multiple Construction Group I chose the Multiple Composite Feature. Is this the right choice? I saved the file as VESSEL.iam 4. Coming with the SAVE operation, INVENTOR creates a subfolder named imported_components where all the single components are saved in.ipt format, alongside with several assembly files named '_GRANITE.iam'. I focused on the main component, which was saved automatically with a serial#.ipt file name, and which I renamed as SHELL.ipt. Examining in further details this SHELL.ipt file, it seems to me that -though well built, as it shows all the nozzle cuts and the welding seam with the proper gap- this file structure itself misses of some components, as for example I cannot see any sketch from wich this component should be derived. I operate the command 'convert to sheet metal'. A pop-up message displays:. Therefore, before any attempt of unfolding, or unrolling, or anyway creating a flat pattern, I take care of setting the proper thickness in the sheet metal stiles dialog box, even if this operation seems a little illogic to me. Let's say that I know that the shell in question has a thickness of 1/4', my further question is: what if I didn't know the real thickness of the shell I had imported? 10, This is the point where I'm stuck: now I cannot perform neither the create flat pattern coomand, nor the unfold command. I' m attaching the file. Is there any way in which I can derive a flat pattern from this shell? Thank you for helping, sorry for the long post. Shell thickness= 1/4' Material= stainless steel. The problem about using exports from these types of programs is you get poor quality CAD files. The cause is the cuts in the face from the lateral nozzles. And your exported model is not 1/4', which you can always measure to set the sheet metal thickness. Try this, delete all the faces except your inside face, thicken the resulting surface 1/4', set the flat pattern thickness to 1/4' and hit flatten. You might need to select a face first. Good to see compress allow export to a neutral format, if they fix all the bugs it might be worth me switching from PVElite. Thanks for your help. Please allow me to post some updates about my progresses. It turned as your hint was helpful, as you pointed on overruling the default sheet metal rules inputing the precise shell thickness. And as a matter of fact, this is all it needs in INVENTOR to resolve the surface and to get to a reliable flat pattern. No matter how many strange splines are present, once you enter the exact thickness the problem is solved. You don't need to perform complex operations such as deleting faces, then extruding, etc. As for the files extensions, I must say that COMPRESS 3D solid model is quite accurate, and it seems to me that either.sat and.step files are optimal to build a solid and well structured model. Maybe I find a little easier and simplier the.sat extension. Firstly the operations are simple, not complex, if you know how to use the software. Secondly you still need to perform these operations to clean up the model, either in the folded part as I described, or in the flat pattern, because you can't build anything off the current output. I'm a pressure equipment engineer so i can assure you that output you uploaded is not correct. It is clear Compress has a long way to go before producing reliable models (but at least they are working towards it). I know you are a little biased though so I will leave it there. As for the file extension, if you have a choice, always choose STEP over SAT/ACIS files. I have no idea where you assumed the false belief that I am biased in favour of COMPRESS, but if I might have implied it in my posts, then I apologize. I am not biased in favour of any software. COMPRESS is the only software I've been working with, and I'm not an experienced user. I am not a pressure vessels designer, I' m a project manager that overlooks many issues daily, and this resolving surface 'thing' is just one of them. Beyond this premise, however your reply raises some questions, which I would like to know deeper your opinion about: - why do you state that, when choice is possible, it is always better to work with.step instead of.sat files? - why in your opinion isn't the COMPRESS solid model reliable just to sort out some kind of planning? I must specifiy this: the reason for our attempt to convert the COMPRESS solid model into something usable by INVENTOR has nothing to do with calculus: all the calculus part is already taken care by COMPRESS. The only reason is because we want to get the drawings done by INVENTOR, and in that case as far as I have seen unltil today it is something that work perfectly. All the shells and nozzles are easily flattened and no further planning is needed. Here is a link that explains some of the differences between SAT and STEP. The link is old but so are the file formats. Post back with any other questions. @IVAN & corysomo My comments regarding compress are limited to the output file supplied by IVAN. The shell penetrations are not correct. To use this model for fabrication I would have to patch the holes and recut the nozzle penetrations. This also leads to poor modelling because I would not have a master sketch and would most likely resort to adaptivity. This basically defeats the purpose of having a fully exported model and it would work better (based on my experience only) to model the file from scratch. This last comment also includes linking parameters to properties for BOM and Part List population. Additionally all my library parts, flanges, manyways, davits, access, etc, have iProperties that automatically populate my parts lists. I don't mind adding weld preps or corner round on nozzles but nozzle locations are critical. If 'COMPRESS' could fix the shell trimming problem and look at exporting properties with the part files then I think they would be onto a winner. Particuarly a market advantage over PVE that will most likely never allow solid model exports because they want people to buy CADWorx. Just one last comment for compress output vs modelling in Inventor: If I fully detail my compress output, then find out from the process guys that two of the nozzles need to be relocated, do I have to re-detail the assembly or modify the dumb solids from the output? I guess your only 'practical' option would be to replace the base view in all the drawings, could be a substantial amount of work though. Does compress have a live Inventor link or is this something they may work towards? FEA software is able to keep these sorts of associations, would be good if PE software could do the same. Inv_kaos wrote: If I fully detail my compress output, then find out from the process guys that two of the nozzles need to be relocated, do I have to re-detail the assembly or modify the dumb solids from the output? I guess your only 'practical' option would be to replace the base view in all the drawings, could be a substantial amount of work though. Does compress have a live Inventor link or is this something they may work towards? If you have to relocate nozzles, there really is no option but to make that change in COMPRESS and regenerate the model. The problem is, when you move a nozzle, you really need to rerun the calculations again. Otherwise, how can you be sure that the new weight distribution doesn't require a corresponding change in the supports? If you have offset the nozzle further from the center, the opening in the shell is now larger and a larger pad may be needed. Like I said before, I'm not an engineer, but I do have vessel examples where small changes invalidate a design because the original was so close to the allowable limits. What you are calling the Inventor link, I call the round-trip problem. We can export the geometry in a format that can be read by Inventor, but going the other way is very difficult as the geometry of a vessel is very constrained compared to what Inventor can deal with. WIth Inventor you could replace a linear weld seam with a seam following an arbitrary path and (as far as I know) there is no way to deal with such a thing in COMPRESS or the ASME codes. Thanks for your comments. I'm very interested in anything else you have to say about pressure vessel software. I am aware of any design limitations and obviously if the angle of a nozzle changes so too will the pad, if it has one. I am less concerned about the supports. But that is the point obviously there will be certain changes in the design that need to be reflected in the drawings. If you used xml files to store all the parameter data for the vessel, you may be able to keep a live link when the design file changes. Have it run as an add in in Inventor with a button called say 'Update Geometry'. Select the button and the inventor files re-read the parameters from the updated xml file and the model updates perfectly! Hence Inventor will still be driven from the design software and not write back the other way. Most FEA programs, such as Ansys, keep a live link and can write both ways. Surely the method I described would not be too difficult to achieve. I started to write something similar for out in house design programs but with the number of permeation a vessel can take, it was becoming unpractical. However you already have this part cover with the design software, I would think keeping live links between the parameters would be the easy part. Cheers, Stew.
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