One of the topics that people often ask is what is the difference between PDM and PLM. The question is almost rhetoric, since the number of explanation is +1 from the number of people involved into the discussion. I stumble on the following article in the FISHER/UNITEC blog – PDM or PLM: Top Down or Bottom Up. There are two important point that caught my attention. First point was about the gap between the product design (CAD) and the layer of managing financials, material requirements and manufacturing planning (ERP). Here is my favorite passage, which clearly position the problem:
Most will agree that the gap between CAD and ERP is too great to ignore the value proposition of the two “middle layers”. However, which should be selected and in what order: PDM or PLM? Additionally, can a typical manufacturer select just one or the other?
CAD Data Management
Wide adoption of CAD system created a crappy problem – what to do with all CAD files and other information CAD systems produce? People are not good in the organization of their data, in general. Engineers are interesting in how to create product design, but not much interesting in how to organize and manage the results. So, CAD Data Management was born. It called TDM, EDM and lately PDM (Product Data Management). As mentioned in Fisher/Unitech blog, many years of CAD data management implementation made it almost perfect:
The PDM solutions marketed today offer near-perfect CAD integrations, because they are typically developed by the CAD vendors themselves and come with a guarantee that new releases of CAD will be supported by them. Additionally, the many complex features of a 3D parametric CAD system are supported by the PDM system available from the same developer. As an example, SolidWorks Enterprise PDM offers simply the very best CAD integration to SolidWorks available on the market.
However, as soon as functional requirements are going beyond simple CAD file management or going beyond support of a single CAD system / environment, the implementation becomes crappy. PDM is a crappy solution for a crappy problem created by CAD.
Product Development and PLM Implementation Gap
Despite well defined, development of systems that support product development from various standpoints wasn’t so straightforward. For many years, ERP was the only system that was visible on the organizational level to manage processes, materials and production. Engineering was considered as a "black box" that needs to be self managed. Engineering supposed to through the results of their work over the wall to manufacturing and execution. The efficiency of this organization was sufficient probably 15 years ago. However, nowadays it is not so anymore. Global development, competition, cost management and many other factors raised need to create more transparency in product development management.
So, the value proposition of PLM became obvious. Now, PLM implementation became the issue. The PLM implementations are complicated, requires lots of service work and corporate involvement. In the real world, only very big companies can handle it. In order to take PLM implementation to mainstream, software vendors created so called "best practices" or "out of the box solutions". It was good for marketing. The reality check didn’t show as a success, in my view. Most of the "out of the box" PLM implementations are not going beyond CAD file management.
Another problem of PLM implementation is CAD file management. In most of the organization, PLM implementation has to deal with multiple CAD (and sometime PDM) systems. Quoting the same blog:
Conversely, PLM systems today provide application support for managing product data and it’s metadata. Applications like engineering BOM management, configuration management, portfolio management, quality management, project management and supply chain management are available and native functions of a PLM solution today. However, because of the many 3D parametric CAD brands on the market, the PLM software developers and resulting systems do not normally have robust CAD data management capabilities that are always in step with current releases and design features, as noted above.
What is my conclusion? I can clearly see the gap between an organizational need to have a robust and scalable system to support product development (let’s call it PLM to be consistent with industry terminology) and maturing of PLM and PDM implementation. For me, bottom up approach makes more sense. People are trying to stay away from complexity these days. The next generation of PDM/PLM will need to take it as an axiom for a future success. Just my thoughts…
Best, Oleg


I see CAD data management as part of the CAD system. EDM, PDM etc. start to deal with deliverables from CAD and PLM is an evolution of that with support for rich change processes and other features.
Keep in mind that not everthing comes from one CAD system. There may be more than one in use. Also there is ECAD and software which have similar structure (source code and library maintenance and production of deliverables to put in PLM).
A new trend is using an integration to make the PLM system the data manager for CAD. This eliminates a system that does not provide a lot of value (although it is definitely needed if there is not PLM). The same can be done for ECAD but I don’t see it taking over the software space because the source code structure is way more complex that MCAD or ECAD.
We only put the final CD image in PLM. For MCAD and ECAD that have no data manager we put the source file in PLM along with the viewable file. For our main CAD system we use the vendor’s data manager but we are considering replacing this with a PLM integration.
Cam
Cam, thanks for sharing your experience. I like the idea of CAD data managers. This is something that lost in traction between PDM and PLM. People are mixing the values and implementations. In my view, best PDMs today are produced by CAD vendors for every CAD. They will become inseparateble part of CAD environment. Think about TC for SolidEdge, Enovia for Catia, EPDM for SolidWorks, Vault for Autodesk Inventor/AutoCAD. Best, Oleg
[...] or PLM: Top Down or Bottom Up? and PDM vs. PLM: Implementation Gaps discuss the conflicts between managing PDM and PLM in conceptual terms. Posted by Scott at 10:00 [...]
Thanks Oleg for a wonderful blog.
My view is that (and you say it yourself midway in the blog) that the PLM effort is a lot like two groups (CAD and PDM/BOM) that start at either sides of a mountain attempting to meet midway. The unsuccessful ones end up creating parallel systems.
Uday, you are welcome! To meet midway or to destroy the wall between engineering and manufacturing is one of the key elements to success in a broad PLM adoption. Thanks for your comment! Best, oleg
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