Tuesday, June 28, 2011

PDM or PLM: Top Down or Bottom Up?

Knowing where to go with your data management strategy, and how to do it, can be difficult to determine with today’s many alternatives. Getting through the acronym’s and nomenclature, let’s start with a simple view of the “layers” of I/T for the discrete manufacturing company today:

ERP Top Layer for managing financials, material requirements and manufacturing planning
PLM Middle layer for managing product data staged for manufacturing
PDM Middle layer for managing product data in development stages up to final release
CAD Bottom layer for creating product design and engineering data and documents

Most will agree that the gap between CAD and ERP is too great to ignore the value proposition of the two “middle layers”. But, which should be selected and in what order: PDM or PLM? Additionally, can a typical manufacturer select just one or the other? Here is my viewpoint of the answers to these two questions.

The summary to both is to always implement bottom – up, not top-down. When you do so, you will maximize the rate of a return from your investment, minimize the risk of a failed or stalled implementation, and improve your visibility to real enterprise requirements that may be difficult to confirm otherwise assess. The discussion below explains.

The first question deals with the order in which to implement: PDM or PLM. 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, many of the PDM solutions, including EPDM, do not provide some of the application support that a full PLM system offers. So, if the company decides that some of these applications are needed, a PLM solution is necessary to compliment the PDM.

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. There are too many brands, release cycles and features in today’s CAD market for any developer to do all this in-house. Therefore, most are outsourcing the CAD integrations to 3rd parties. So, at the end of the day, your PLM system will usually consist of software developed by two different developers: one for the PLM and one for the PDM. You end up with the same situation as above. Only, in this case, with a lower quality of PDM solution.

If a company elects the “bottom-up” approach, they can optimize on both. If they elect to implement “top-down” they will optimize on one and forfeit important functionality in a very critical area: managing multiple versions and releases of parts, assemblies and drawings. Getting the product definition right, and to those who need it promptly, is the first and foremost responsibility of a solution in either area. With the pressures of the global manufacturing community, there can be no tolerance for an error in release levels and the correct product documents behind them.

Advancing our discussion to the second question: can one or the other, PDM or PLM, be omitted from a final implementation for the typical discrete manufacturer? If you have a 3D parametric CAD solution in place, you should never avoid the PDM layer. So, can the PLM layer be omitted? That will depend on three factors: the complexity of your product structure, the level of vertical integration available in your manufacturing resource, and the capabilities of your ERP system. Many products have a simple enough product structure that PLM is not needed. Some of the ERP solutions on the market have modules for PLM that are included or available.

Finally, a PDM implementation is usually considerably less complex than PLM. That results in lower implementation costs, faster project times and lower implementation risks than PLM. With the benefits of PDM being realized early in the total project cycle of an implementation of both, the total risk is thereby reduced, yielding a better ROI back to your company.

In summary, I recommend all companies start with a good quality PDM solution, and advance, if necessary, to a full PLM solution when the PDM layer is complete. The “bottom-up” approach is best.

1 comment:

Anonymous said...

This is a very good article. Nice Work! If you don't have control over your associative Cad database, look what happens to the references when you change a part name at the end of the design cycle- chaos

Keep up the good work.Education is key and customers appreciate the assistance.

Steve Ammann
Zero wait State
sammann@zerowait-state.com