Multiple dimensions of BOM complexity

Multiple dimensions of BOM complexity


Bill of Material topic is getting more attention these days. No surprise. BOM is a center of universe in manufacturing (and not only) world. People can disagree about terminology applied to BOM management. Depends on a specific domain people can call it part list, specification, formula. But at the same time, everybody speak about the same BOM. Actually, not always the same BOM. I guess you’ve heard about variation of Bill of Materials – eBOM, mBOM, xBOM, etc. The amount of abbreviations in BOM is growing and often can cause confusion. So, I decided to put some lights on that in my post today.

The importance of BOM management is growing as well as tension around who owns bill of material. Historically, people in different departments disagree about the way they manage bill of materials. As a result of that, departments are splitting and cloning bill of materials to get control and  managing it in different systems. It leads to the need to synchronize and copy BOMs together with changes. The tension around BOM management is growing. Last year, I posted some of my thoughts in the post – Will PLM manage enterprise BOM? The main point in this article was around complexity of BOM management and integration between different systems and disciplines.

It looks like BOM will become the next place some of PLM vendors are going to innovate… and battle. My attention was caught by provocative ENGINEERING.COM article – The Power of Zero – Dassault’s ENOVIA chief talks about the ”Zero Error BOM”. Read the article and draw your opinion. I captured the following passage:

The “war” has generally been about linking product development with shop floor IT and the BOM certainly plays a key role in this. Right now there are four primary participants on the battlefield: Siemens, SAP, GE/PTC and IBM.

Article is emphasizing the complexity of “universal BOM” solution and potential advantages of winning BOM battle:

It’s not a simple job to manage a BOM. What might appear as ”a list of parts needed to build a product” is today a complex reality of multiple levels, diversified disciplines and BOMs contains information about structures, electronics, integrated software, manufacturing methodology and the way products are maintained and even disposed of. There are many sources of error and mistakes can be very costly.

If Dassault’s “zero error BOM” can become a reality, it’s a huge step forward and would, according to analyst Marc Halpern of Gartner, ”have the potential to realize the ’dream’ of the universal BOM”. But as Kalambi says: ”This is about to embark on a journey; once on ’the road’ the benefits of 3DEXPERIENCE and V6 will increase productivity dramatically”.

I found myself thinking quite a bit about complexity of BOM today and, as a result, came to the following diagram showing 3 main dimensions of BOM complexity: Disciplines, Lifecycle, Changes.


1- Multiple disciplines. The complexity of product is growing these days. Even for very simple products it goes beyond just mechanical and electromechanical design. It includes electronic, software and goes to services and deliveries. Engineers are using multiple tools to create design of products in each discipline. To combine everything together is a very challenging task.

2- Lifecycle. Design represents only one phase of product development. It must be manufactured, shipped, supported and (after all) re-furbished or destroyed. All these processes are going in parallel and requires sophisticated interplay in data and activities. How to connect requirements with design, plan and optimize manufacturing and run support services? This is only a short list of tasks that requires BOM orchestration.

3- Changes (ECO/ECN…). Nothing is static in this world. People are making mistakes. Communication failures happen. Suppliers are going out of business. All these events generate changes that must be applied into different stages of product development – design, manufacturing, services.

What is my conclusion? Bill of Material management reflects one of the most complex disciplines in product development and manufacturing these days. The time when companies managed BOM on the shop floor corkboards are gone. Future BOM management systems will have to be much more sophisticated, integrated and to support multiple dimensions of BOM complexity. Just my thoughts…

Best, Oleg

[update 16-Oct-2014]. The BOM complexity diagram was updated following comments about ECR-ECO-ECN


Share This Post

  • Kurt

    Hello Oleg,
    thanks for this compact description of todays requirements for full BOM management.
    I think a powerful and well customized PLM system should be able to address most of them.
    Allow me just 2 hints to your nice graphics “BOM complexity”:
    1) I miss a further “sub-dimension” on axis Lifecycle: plant specific BOMs when you have global distributed R&D and manufacturing. Maybe you should add that for “full view”?
    2) The axes “Changes” shows ECO->ECN->ECR, isn’t it ECR->ECO->ECN ?
    Thanks again,
    Regards Kurt

  • praveen.p

    Thanks Oleg for the wonderful article.
    Hi Kurt,
    I completelty agree with your point on Plant specific BOM view.
    for the second point about the “Changes” considering the new BOM release it will start from ECO –> ECN –> ECR.

  • Kurt

    Hallo Praven,
    maybe we just have different meanings of the abbreviations 😉
    Let me explain my Engineering Change (EC) abbreviations, based on my experience, I would quickly define them this way:
    1) ECR “Request”, describes the problem and possible fix(es).
    If approved by all approvers it creates an ECO. (Sometimes also n:m relationships!)
    2) ECO “Order”, describes all items that need to be changed (drawings, specs,
    BOM etc)
    3) ECN “Notification”, describes the final executed changes and informs all involved people / departments and will need effectivity (valid from in diff. plants)
    and sometimes additional ECI “Implementation” procedure / steps…
    What is your understanding?

  • Loic Mouchard

    Hi Oleg,
    the fourth dimension would certainly be the RFLP (Requirement / Functional / Logical / Physical ) description of the product structure?
    I’m not quite sure to understand the meaning of the graph and I’m quite surprize that you do not mention the configuration management. From my point of view, this is what brings the most complexity in the management of BOMs.


  • yarivsade

    Hi Oleg,
    Thanks for raising this issue.
    No doubt that BOM data is much more important than its current industry’s position. I believe the potential of making better cost-effective products in faster time to market, based on enhanced BOM data, is just beginning.


  • beyondplm

    Hi Yariv, thanks for your comment! BOM data plays a key role in the ability of manufacturers to optimize product at any stage of lifecycle.

  • Vladimir

    Hello Kurt,
    I absolutely agree with you regarding the definition and direction of ECR->ECO (ECN).
    Regards, Vladimir

  • beyondplm


    Besides the fact I don’t know how to draw 4D diagram (:)), I found your observations about RFLP very interesting. Thank you for mentioning that. It is important.

    Here is my take on how RFLP relates to 3 dimensions I described. I think, it partially belongs to product lifecycle (I almost put “requirements” stage before “design” when I draw this diagram). On the other side, configuration management has many common elements related to “change processes”.

    It looks like I need to put some more thinking towards BOM and System Engineering topic and come back with separate blog about it. Thanks for the inspiration!

    Best, Oleg

  • beyondplm

    Hello Kurt,

    Thanks for your comments! Yes, ECR-ECO-ECN will be more applicable. Your are right. Will have to make v2 of the diagram. Globalization is an important part. Today, even small manufacturers are distributed. It will develop into a broader view of design and manufacturing supply chain.

    Do you have any assessments about “powerful and well customized PLM systems” and existing PLM vendors? I guess, every PLM (and not only) vendor is considering BOM as one of the most important PLM functionalities. The devil is in details, of course.

    Best, Oleg

  • Pingback: The role of Bill of Materials (BOM) in PLM competition | Daily PLM Think Tank Blog()

  • Pingback: The role of Bill of Materials (BOM) in PLM competition()

  • Pingback: Beyond PLM (Product Lifecycle Management) Blog » Who’s ready to manage complexity of BOM for connected cars?()

  • Pingback: Who’s ready to manage complexity of BOM for connected cars? | Daily PLM Think Tank Blog()

  • Pingback: Beyond PLM (Product Lifecycle Management) Blog » Spreadsheets vs PLM dilemma to manage BoM()

  • Pingback: Beyond PLM (Product Lifecycle Management) Blog » Who needs single source of truth for BoM?()