With 'logical' part numbers, parts are easier to find when you don't have a searchable index, but you run out of numbers sooner, always in just a few 'categories'.
Computerized inventory control and production management systems have trouble with 'logical' or 'significant' part numbers.
Sequential numbering systems, e.g., numbers without significance, make it harder for people to find stuff without the aid of computers, but it's easier for the computers.
An electronics company of my acquaintance used a part numbering system derived from EDN's catalog system; Numbers starting with 48 were for electronic components. The second pair of digits were for a type of component, like resistors. The remaining three digits were assigned in sequence.
Their worst blunder was getting locked into a mainframe- based production management system that limited part numbers to seven digits, so when they had used up 999 numbers for the most common components, they had to start abandoning the significance of the numbering system. It took 20 years for it to become an acute problem, but it was a monster of a problem, because every screen you saw in the system was a separate program, and they were all hard- coded to 7 digit part numbers.
The mainframe programming department thought a backlog of ten years was about right, and started layoffs when it got down to two years. They were part of the problem.
Whatever else you decide to do, make the part number field real wide.
Mike Halloran
NOT speaking for
DeAngelo Marine Exhaust Inc.
Ft. Lauderdale, FL, USA