Manufacturing Part Numbers 




Arguments for Significant Part Numbers

Two reasons for using significant part numbers go back to the beginning of "management information systems." Thirty years ago, a big computer installation had memory measured in "K" rather than "M," and it wasn't uncommon for there to be one or two display terminals (for that was what they were—cards were used for input, not keyboards) for several hundred people to share. Not only was there a minimal amount of information on the computer system in the first place, but access to that information was very restricted. Additionally, it was very important that those slow, ponderous mainframes not experience any problems in their calculations. Error detection and recovery couldn't be readily programmed into the machine's algorithms, so the system was made more robust by artificial constraints that would allow bad data to be easily rejected at the front end. These constraints led to two uses for part number significance: first, to replace a needed description field or to allow access to the description without requiring access to a display terminal; and secondly, to avoid working on a "bad" part number.

The first required a part number that actually conveyed informa­tion. In many cases, the part number prefix revealed the type of part—whether bushing, spring, resistor, capacitor, etc. That way, the person confronted with that part number at least knew what list to consult to discover what the part number represented. That was faster than waiting in line to use a CRT. The second use required that the part number have a certain form to be accepted by the computer at all. For example, it may have required that the part number have three numbers, followed by a dash, followed by six numbers. This second use led to additional significance over time, as more plants came on line in large corporations. At one facility with which I was familiar in the early 80s, we were allowed four prefixes for our part numbers—to make sure that they were kept separate from the part numbers used by other parts of the corporation.

There is little if any reason to consider these reasons any more. Most organizations now have a CRT that can access MRP inform­ation for every two or three employees—some have more than one per employee. It's quicker to look the part number up on the item master when there's a question—and besides, a description field is almost always displayed alongside the part number on most screens. More capable software and distributed computing has effectively removed the second use for significance as well.

There are still other arguments for significance. Many of them are based on "what if scenarios:

• What if the system goes down, and I need to know the description of a part?

• What if I'm out on the road, and I need to repair a product, or replace a part, and don't know its description?

• What if I need to order the part, and the system goes down, and I don't know what to tell the supplier?

• What if I want to have my automated assembly equipment check to make sure I have the correct part before putting it on my product?

• What if production is a harsh or "clean" environment (there­fore has little access to the system), and I need to make sure that we're using the correct part?

• What if I want to organize my stockroom by part type (all the resistors in one set of shelves, all the hardware in another)?

All of these are perfectly valid reasons for a significant part numbering scheme, but they can also be accomplished by other means. The other means are: a properly organized and printed part number listing, relational databases, and commodity coding. We'll discuss those briefly after examining some of the arguments for using nonsignificant part numbers.

To be Continued


To stay current on bullet-proofed manufacturing solutions, subscribe to our free ezine, "The Business Basics and Best Practices Bulletin." Simply fill in the below form and click on the subscribe button. 

We'll also send you our free Special Report, "Five Change Initiatives for Personal and Company Success."

  Your Name:

  Your E-Mail:



Your personal information will never 
be disclosed to any third party.

Manufacturing leaders have a responsibility to educate and train their team members. Help for developing a self-directed, World Class Manufacturing training program for your people is just a click away:


You are welcomed to print and share this bulletin with your manufacturing teams, peers, suppliers and upper management ... better yet, have them signup for their own copy at:


With the escalating spam-wars, it's also a good idea to WHITELIST our bulletin mailing domain via your filtering software or control panel: 


This will help guarantee that your bulletin is never deleted unexpectedly.

Manufacturing Knowledge you’ll not find at offsite 
seminars nor in the books at Amazon.com

Lean Manufacturing - Balanced Scorecard 
ISO 9000:2000 - Strategic Planning - Supply Chain 
Management - MRP Vs Lean Exercises - Kaizen Blitz 
Lean Six Sigma - Value Stream Mapping

All at one Website: Good Manufacturing Practices


World Class Manufacturing Menu

 Assembly Line Simulations

Lean Manufacturing Training Articles

Best Manufacturing Practices Archives

Manufacturing Best Practice Bulletin Archives

Linear Operations Survey

Lean Manufacturing Consulting

Lean Manufacturing Consultant

Kaizen Management

World Class Manufacturing Certificate Program 

Resources Links

Lean Manufacturing Training for anyone ... anywhere ... anytime
Business Basics, LLC
6003 Dassia Way, Oceanside, CA 92056
West Coast: 760-945-5596

Lean Six Sigma Consulting   World Class Manufacturing   
Balanced Scorecards  Strategic Tactical Planning  
Supply Chain Inventory Management
  Principles of Total Quality Management
  Manufacturing Process Improvement

Email: Click here  Privacy Policy