One Part, Five Numbers
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Everyone worries about the same part number hiding two different parts. Almost nobody audits the opposite: the same part hiding behind five different numbers.
One failure gets you a recall. The other quietly invoices you every single day.
Think about what a duplicate part number actually is. Two parts that could fully replace each other in Form, Fit, Function, and Interface, but do not claim to. It is the interchangeability promise broken in reverse. And because nobody made the claim, nobody collects the benefit: duplicate stock in two bin locations, duplicate qualifications, duplicate supplier negotiations, missed volume pricing, and engineers redesigning what already exists on a shelf.
The cost is higher than most people guess. PTC’s example puts the lifetime cost of one new part number at $15,000 net present value, covering creation through planning, stocking, and maintenance. In their model, an organization introducing 10,000 parts a year that catches just 160 duplicates saves about $2.4M annually. Those are illustrative assumptions, so run your own numbers: take what a part number costs your organization over its life, and multiply it by the duplicates you have never counted.
Here is the part I find most interesting. CM2 refers to Naming, Numbering, and Reuse. Reuse is not an afterthought bolted onto identification. It is the same discipline pointed in the other direction. A numbering scheme that controls interchangeability is also the search structure that lets a designer find the existing part before creating its twin.
In other words, duplicates are not a data hygiene problem. They are unclaimed interchangeability. The organization owns the equivalence but has lost the knowledge of it.
And CM2 has a template waiting for exactly this: the equivalent item record, where parts with different identification numbers that remain fully interchangeable are cross-referenced. Different numbers are not the problem. In the article, I argue they are sometimes the honest answer. The problem is different numbers with no claim between them: nobody validated the equivalence, because nobody knows there is one to validate.
So, honest estimate: what percentage of your part catalog is duplicates? And who in your organization would even be able to find out? Let me know what you think.
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Copyrights by the Institute for Process Excellence
This article was originally published on ipxhq.com & mdux.net.