If we consider the humble part number. What is it’s purpose?
In essence, a part number is simply a unique identifier for an item approved for a specific application. It’s formatting should be consistent, and remain unambiguous throughout that items lifecycle. This is essential for correct product assembly, testing and maintenance.
A good part number therefore simply allows us to clearly distinguishing one part from other.
There are other good practices we should consider though.
- Numbers should have a consistent number of characters, noting that based on research a string of more than 7 characters increases the risk of data entry errors and are a lot less memorable
- Numbers should have a consistent format that is easily identifiable and not prone to being truncated if reproduced in another system where (for example) leading zeros are not permitted in a field.
To address the above customers will typical employ perhaps one of three approaches.
- Simple Sequential Document and Part Numbers. These can be assigned by PDM out of the box and can also be configured to include a fixed component (a pre or post-fix) that when added to a PDM file Template or file specific DataCard can create a semi-significant scheme that, for example, distinguishes between Parts and Assemblies through a basic mnemonic (P for Parts, A for Assemblies etc). Semi-Significant or Significant / Intelligent Part Numbers, which require human interpretation and assignment, can take a number of forms
- Semi-significant numbers can be assigned where simple classification requirements vary a prefix based on a high level classification. This could be to differentiate between a designed component and a bought in part. This could also be to tag a component as being Project or Product Specific, by (for example) including an inherited Project or Product number within the prefix that the sequential counter is assigned to. It could also be used to differentiate between types of Assemblies, where (for example) a top level arrangement is numbered differently to the subassemblies that make it up.
- Significant / Intelligent numbers are often built up of a number of discreet components that can describe the part or assembly using codes to illustrate things such as a component category and sub-category / type, specific options, colour, finish and even Revision. These tend to be hangovers from a Pre-CAD era and often have accompanying ‘guides’ that a new employee must learn. This learning curve is not straight forward however, as there are often outliers – new variants and exceptions that do not fit within the original design of the Intelligent part numbering system.
The Brisch system is an example of a classification model widely used from the 1950’s onwards. It consists of seven digits and is applied in three phases. The items are grouped into suitable preliminary categories, such as assemblies, sub assemblies, components, off the shelf items. After these preliminary categories, items are grouped with in the respective groups in order to bring similar items together.
These sorts of approaches, although common are rarely flexible enough to remain in sync with technology, engineering methods, materials and processes over a prolonged period of time.
“The most critical of these issues is that over time the significant numbering systems tend to break down... As time passes variations arise which were not foreseen. One digit was set aside where two are now needed. Significant numbers thus tend to lose their significance. They no longer do the classification coding function intended by their inventors.”
Watts: Engineering Documentation Control Handbook page 49.
Although Solid Solutions would advocate the use of a Simple or Semi-Significant number within PDM; with metadata being used to describe the component in a much more ‘user friendly’ and sustainable way. We appreciate that Customers will in some cases not be able to shake off a legacy numbering scheme or will require a small degree of intelligence that is not possible ‘Out of the box’ in SOLIDWORKS PDM. For this reason we have developed the ProjectNumbering Serial Number add-in for SOLIDWORKS PDM Professional.
The add-in is linked to a PDM ‘Serial Number’ which enables it to be triggered via Save (inside SOLIDWORKS), via DataCard (default value), Template Card, Copy and Move Tree.
- Single ‘Serial Number’ component can generate many configured number types.
- Default ‘Number’ can be specified
- Numbers can contain up 10 elements with the ‘Key Index’ used to allocate a specific numeric counter to the configured number.
- Multiple Elements can be combined to create the ‘Key Index’. Elements consist of…
- Fixed Text / Separators
- Folder Variable values inherited from the Folder Card associated with the location of the new ‘part’ (e.g. Project Number)
- PDM Lists (using the ‘Alias’ type lists in PDM Professional we can select descriptive text from a list that adds a predefined Alpha / Numeric string to the ‘Key Index’
- Counter (specify string length, initial value and increments)
Project Numbering is already included as standard for Customers taking our FOUNDATION Implementation Package for PDM Professional but can also be purchased as an add-on for any existing PDM Professional Vaults.
For a more detailed view of the add-in in action take a look at this short video demonstration.