Best Practice - Material Codes + Part Numbers?

[Slagathor]

I am huge proponent of Non-Sig part numbers, with carefully predefined field hierarchies for description creation withing families. I also like pre-defined ranges for specific types of parts. Here is an example of a 7 number system. See linked PDF here:

https://www.dropbox.com/sh/05vywxnj6msltld/AAAx-296MsSoVN0WHwaVeVRUa?dl=0

In this scheme, each part family has a predefined range from which you can create non-sig part numbers. For instance, the 4th part in the SB family that is created would have a part number of 241-0004. So the only intelligence in the system is that you can look at the prefix, and know what sort of part you are talking about. This had advantages for inventory control and item handling in the facility.

Also, each family has a predefined sequence of descriptive fields, based on the family.
Description Field 1 (Primary) - 'Shaft' for the SB family, but 'Hardware' for the HW family
Description Field 2 - Could be 'Drive an SB family part, but 'Screw' for a HW family part
Description Field 3 - Could be 'Threaded' for an SB part, but Cap for HW part
Etc.

Result:
Shaft, Drive, Threaded, 1.50", 60"L
Hardware, Screw, Cap, Socket Head, 3/4"-10, 4"L. Full Thread

So here is my question. Let say I have this part 241-0004, and it can be made from a variety of materials. 416ss, 316ss, C1045, 17-4PH, 4140, Nitronic 60. Currently in our system we would have a single part number, but material codes that are attached to the part number. This is the the legacy ERP system is structured. So, the actual definition of the part would be 241-0004-1197, where 1197 is the code for A582-416SS. Is this bad practice? In reality, material codes are a version of a smart numbering system. Should non-sig systems be to rigid as to exclude materials codes? If we hold to this, that would mean I would need 6 part numbers to cover this one shaft design that can be machined from 6 different alloys.

 

[TheTick]

It's a good practice if it works.

Like you, I lean toward non-sig part numbers. But, I am not a rabid fundamentalist about it. Over-classification causes more problems than can be solved by reading the and MRP information.

However, a little "smartness" is good, if it works in a way that is not cumbersome.

 

[JMirisola]

Where they all use different materials, they are different parts. One would assume that each material is used for specific applications, so the different part numbers would help to ensure the wrong part doesn't end up in the wrong place.

Jeff Mirisola, CSWE
My Blog

 

[EEnd]

What you describe seems reasonable.

A good indicator of too much "intelegence" in a numbering scheme is that it becomes difficult to determine what number should be assigned to a new object, and this does not seem to be a problem with your system. It also looks like it would be good for answering the question "Do we already have a part number for this made out of 316ss?" That question would otherwise be difficult to answer outside of a very rigidly defined naming / description scheme, which would likely be more effort to develop, maintain and enforce than your current numbering scheme.

I have only one minor tweak / critique. In your description, you refer to the first 7 digits as the part number and the last 4 as the material code, and mention that the actual definition is the combination of the two. I would adjust your thinking / terminology so that the term "part number" was reserved for the full 11 digit number. Its prefix is the family code and, its suffix is the material code. It should not change what you are doing in practice, but the correct distinction will help lead people to the correct behavior.

For instance, most systems consider the part number as the unique identifier. If someone thinks of the part number as just the first 7 digits, they may be tempted to enter just the first 7 into the system and then look for some place to put the material code. Then when they encounter the next one that differs by just the material code, they cannot use just the first 7 as the part number, and they end up making up some scheme to provide uniqueness. If you are lucky, it is by adding the material code as a suffix, but if they always though of the full 11 as the part number, they would have started out in the right place.

You may need to make up a term for the 7 digit number, to keep people from referring to it as the part number, although I am not sure how often that occurs outside of discussions of the numbering scheme. The term that I came up with was "geometry code".

Eric

 

[Slagathor]

EEnd,

What that essentially means is that the Solidworks PN system and the ERP PN system do not have to be exactly the same. ERP PN = 11 digits. SW Doc Control = 7 digits. ERP PN = SW PN + Mat Code. I am OK with this little bit of intelligence being built into the system. That means that the drawings and solid files for the SolidWorks Part need to have a Generic Material assigned, making it clear that the actual material code is required to make a valid 11 digit ERP Part number.

I agree that there is no need to go overboard on non-sig philosophy.