Global Material Callouts

[jim_mcconnell]

Hello All,

We have several global manufacturing sites in Europe, Asia, and the USA. In order to minimize our business risk at any one facility we are setting up to assemble identical products at anyone of those sites. Currently the majority of work content is done in the USA but we have flow lines set up in Asia to do a small percentage, however the material is generally shipped from here to the other global sites for assembly. Ideally we would like to have each site to be able to use local manufacturers and material sources to produce common products, there are many cost benefits to doing this. I would prefer one set of drawings and have the parts to be functionally interchangeable. The issue we are experiencing is that although materials may be equivalent structurally they are not exact in composition which causes concerns with our RoHS and REACH folks. Their solution is multiple sets of drawings/pn#'s. How do others handle this? Do you normally have drawings that call ASTM on one set and GB or EN on another?

Looking for ideas...

[Kelly_Bramble]

I assume you're referencing structural steel and other materials?

Engineering drawings and associated material/parts list often have "Alternate Items" for each material or component.

For structural shapes the end item design can be dimensionally specified exclusively to the critical or relevant surfaces. Then, each structural member "Alternate Item" is a similar structural shape pre-specified by the design engineering activity. If an item is identified as bubble # 12, the parts list could show multiple items and materials that are acceptable as item #12.

This is the way to have one engineering drawing that can be distributed to multiple locations. The engineering drawing could also have notes clearly indicating that items can be procured depending on availability.

Multiple engineering drawing sets are also possible however managing a parts and material list is often more practical.

[jboggs]

What Kelly said - "acceptable alternates".

[jim_mcconnell]

Thanks for the quick responses Kelly/jboggs
Alternate items are generally not allowed i.e McMaster-Carr as an example. They source from different suppliers which makes it impossible to document and collect RoHS data. I'm talking specifically ASTM A36 plate, which in the USA, is readily available in various inch sizes. China for example has GB/T 700 Q235 which is readily available in metric sizes but will differ in alloy composition and mechanical properties from A36. We can design to the lower strength material but the form size is different (due to the imperial/metric conversions) which will effect the rigidity of the suspended mass (another pandoras box). The real issue that we face is that we're required to have certificates of compliance for EHSM purposes and although the steel may be deemed functionally equivalent its not the the same in composition so the guidance is to create different part #'s or dash #'s.
I'm just curious how other large medical device corporations under FDA regulations such as GE, Elekta, J&J handle their drawings since I'm sure they all use multiple global manufacturing sources.

[Kelly_Bramble]

Your post is all over the place.

1. If you’re specifying an OEM proprietary part/component and there’s not an equivalent alternate item, you’re stuck. In general, it’s not a good ideal to design in proprietary sourced anything. I’ll go further and write that specifying line items in you BOM that sources a specific company and part number is very-very short sighted.
2. RoHs or invoking other industry standard material trace-ability from organizations like McMaster Carr creates the proprietary and single source challenge. Assuming they do this, there will be an extra costing involved. In general, parts procured from the Home Depots, Lowes, etc. are unknown materials quality. I have stainless steel fasteners on my boat from a hardware store that are NOT quality Stainless Steel.
3. If you’ve designed a machined part or other alternate material candidate item requiring sourcing with country or industry specific trace-ability, this can be done in the materials/parts list. When in design and engineering analysis, design around the material that exhibits the least strength, heat transfer or whatever is mission critical.
4. Again, when using standard shapes and sizes, like tubing for a fluid, you can alternate item specify industry sizes and associated hardware. Design around the least performing item.
5. Of course, you can just create multiple engineering drawing sets for each region or country.

Being careful with the words I write (as I am under many NDA’s as a trainer/consultant) – not all big corporations, medical, aerospace, defense, sciences or whatever practice modern smart design engineering methods, or practices. Many engineering design organizations almost completely ignore sourcing issues during the design phase driving end item costs up. Material interchangeability is a common challenge and too often the design engineering solution is the most expensive one an organization can dream up.

[jboggs]

Sounds like your problem is bureaucracy and red tape, not engineering.