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Calling out standard bolts on drawings & bolt certs

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bc1080

Mechanical
Sep 11, 2015
20
In our work we usually (pretty much always) deal with NAS fasteners and so we are use to having a very specific fastener code to place on drawing EPLs to allow the shop to order the exact fastener we need from any number of industry vendors. We are now designing a piece of tooling and are wanting to use standard Grade 8 bolts. We are struggling to find any part numbers or standardized "codes" to place in the parts list to indicate a specific fastener. I know the bolts (for example) are SAE J429 Grade 8 bolts (which use dimensions from ASME B18.2.1). I have tried to describe the bolt like follows:
SAE J429 GR8, 1.0-12X3.0
But the shop says this is not specific enough for them to order a fastener. The only thing left I can think to do is narrow it down to a vendor and use their unique product ID/SKU number on the EPL, but this removes flexibility for the shop to be able to use other vendors if they are out of stock or find a lower price (without having to rev the drawing to change the code or approve an alternate). I am wonder what other engineers/fields do to call out "normal"/Grade 8 bolts that do not have a standardized coding system similar to NAS.

In a related question; we do not need the traceability of the NAS bolts, but are not sure if there are options where we can get some intermediate forms of certification (lot certs, etc) that satisfy that the fasteners meet at least basic material and strength properties and that they are not forgeries. I was around at a past job when this issues was dealt with and solved, but I was not directly involved so I may not be remembering the terminology or describing it 100% accurately. Does anyone know what I am trying to describe in terms of something between a NAS bolt and grabbing something from a bulk bin at a hardware store? We are trying to not get pushed into two extremes where it is either full certs or no certs at all.
 
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Even with a VICD, QA still should inspect the parts for conformance to the stated engineering requirements. VICDs can be used to shield the customer from seeing anything but the company part number and slows them from going direct on COTS items. The primary reason is to recognize that COTS items exist and that suppliers aren't going to create a supply just for a small number of items, particularly for things like Integrated circuits, where the effort to generate a full product description is excessive, but only some suppliers are known to meet particular performance requirements or for fasteners where the mass market doesn't warrant it.
 
Per ISO VICDs add risk and should only be used when absolutely necessary (ie. complicated parts/assemblies). Using them for fasteners IMHO is unacceptable bc it needlessly eliminates a pokayoke in the procurement process. Ordering via company standard/spec drives every supplier to review (or at least accept) your requirements and very effectively shifts responsibility for every lot purchased onto them. Using VICDs you will eventually find your company taking a loss because your purchasing dept blindly cut a PO for supplier p/n XYZ with no performance/inspection requirements. If you are concerned about protecting your parts business VICDs also needlessly add risk, without them nobody within your company knows nor can leak supplier p/ns for common hardware.
 
CWB1 - Perhaps ISO has a different interpretation than ASME. No supplier for hardware will accept this without it being a very expensive item because they are forced to identify their mass-market part with your custom part number.

I already said that VICDs have performance and inspection requirements that are verified by incoming QA. If your QA isn't doing this, they are the ones putting the company at risk. As for losing sales, 100% of the time procurement will know, and have the most external connections, so they can leak that info. Not using VICDs is not going to stop that.

Perhaps your company has been misusing VICDs, which is the most likely explanation. If you have leaks in the organization, someone will leak the entire drawing package along with the buying history.
 
Thanks again for all the answers! We got tied up with a lot and I got pulled onto a different project and this fell to another engineer to try to figure out. It was more of the ordering issue at this point, we determined that we could get acceptable bolt/material certs from several vendors (just had to ask them individually if they could provide this), so it was not a "buy from the catalog" type situation, we had to get special quotes.

The main issue has remained that our shop demanded unique and exhaustively specific codes/product for every individual product/fastener they had to buy. We actually did try to use the ASME ordering code system, but found the suppliers didn't really know what to make of it.

Ex, our shop wanted:
xxxxxxx = SAE J429 GR8, 1.5-12X3.0 UNF-2A cap screw, zinc plated
yyyyyyy = SAE J429 GR8, 1.5-12X4.0 UNF-2A cap screw, zinc plated
zzzzzzz = SAE J992 GR8, 1.5-12 UNF-2B nut, zinc plated
= SAE flat washer, zinc plated
...
For each of the dozens of different common fastener line items we were needing they required a single part "number" to order to.

The only way the team could find to do this was as mentioned, to select a particular vendor and use their internal product codes and a "supplier" column on our EPL. This doesn't make much sense to me as it defeats the point of using a "common" fastener by specific it must be bought through this one vendor. Our management was ok with having to spend the engineering time to change the drawing if they needed additional fasteners in the future and needed to use another vendor. Every time we need to add a fastener or vendor, we are going to just add a new product ID and vendor as an alternate. This is made worse as in this situation we were very limited what drawing and release options we could use because of some special tracebility requirements on this project and rules not allowing us to "reassign"/"renumber" commercially sources parts unless we modify them, and our quality not allowing any substitutions without it being on the drawing. (we used to have an "or equivalent note" that allow us to approve a different fastener than initially selected).
 
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