Inconsequential nonconformances

Excuse me if this has been covered already. new member, first post. i just started a new role in a manufacturing company and i am trying to get better control of metrics surrounding NC. one of the issues i have come across is we write a lot of NC for scratches, dents and dings on surfaces of parts pulled from stock. the issue is that we have know way of knowing how or when they got there since we do not do 100% inspection when the parts come back from painting. furthermore the VP of Operations is of the belief that it is not worth the effort and the cost to investigate because it is usually 1 or 2 pcs out of hundreds or thousands. the problem is that we use a quality software for logging NC that does not allow the NC to be voided once it is opened.

So how should i log this type of NC in a way that an auditor would understand.

If parts are non conforming, they should be recorded and they can be dispositioned as scrap, rework, repair, use as is, whatever. What you don’t want to do is to trigger a corrective action for spurious defects. Two separate issues.

LoBo. said:

Excuse me if this has been covered already. new member, first post. i just started a new role in a manufacturing company and i am trying to get better control of metrics surrounding NC. one of the issues i have come across is we write a lot of NC for scratches, dents and dings on surfaces of parts pulled from stock. the issue is that we have know way of knowing how or when they got there since we do not do 100% inspection when the parts come back from painting. furthermore the VP of Operations is of the belief that it is not worth the effort and the cost to investigate because it is usually 1 or 2 pcs out of hundreds or thousands. the problem is that we use a quality software for logging NC that does not allow the NC to be voided once it is opened.

So how should i log this type of NC in a way that an auditor would understand.

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If it's me, I drop a dollar amount on it. I wouldn't write anything if it's a few pcs. and less than a few dollars. Scrap them and move on. If you feel you have to log them, can you log and close instead of void. That way you have a record but not a lot of effort.

LoBo. said:

Excuse me if this has been covered already. new member, first post. i just started a new role in a manufacturing company and i am trying to get better control of metrics surrounding NC. one of the issues i have come across is we write a lot of NC for scratches, dents and dings on surfaces of parts pulled from stock. the issue is that we have know way of knowing how or when they got there since we do not do 100% inspection when the parts come back from painting. furthermore the VP of Operations is of the belief that it is not worth the effort and the cost to investigate because it is usually 1 or 2 pcs out of hundreds or thousands. the problem is that we use a quality software for logging NC that does not allow the NC to be voided once it is opened.

So how should i log this type of NC in a way that an auditor would understand.

Click to expand...

What is your disposition for these materials? If these are dispositioned scrap in every instance I recommend an update to your NC process wherein you can evaluate NCs via alternate method based on risk and thus lessen the burden per NC.

Something I have done and seen within other manufacturing environments is where low risk and high detection materials/product can be scrapped outside of the larger NC tool/process by use of a form with minimal signoffs (documented and supported by the process of course). You'll also want to evaluate if you need some mechanism to trend if you go this route.

Other things you might need to take into consideration are if you have classes of parts and your considerations of those with CTQ or CTS notes applied. @Golfman25 brings in a good point to evaluate based on cost as well to lessen the burden of conducting a full blown NC, caution here though depending on your disposition and the part's classification. I would recommend against a one size fits all based on cost alone because other parts outside of the specific one in your post come into play. For instance I have a WI which specifies parts, by PN, we can directly scrap outside of the normal NC system based on cost, risk, and part classification.

Hope that helps a little or gives some alternate paths for thought

Golfman25 said:

If it's me, I drop a dollar amount on it. I wouldn't write anything if it's a few pcs. and less than a few dollars. Scrap them and move on. If you feel you have to log them, can you log and close instead of void. That way you have a record but not a lot of effort.

Click to expand...

this is exactly what i am trying to do. i just don't know what terminology to use for the reason. for example, if we investigate a potential NC and find that the NC is not valid, we log it as "NC Not Valid" with an explanation such as "Part found to meet spec" so I'm just at a loss for how to log something that is a valid NC, but we just don't think the cost outweighs the effort. we disposition it as scrap or sometimes rework and move on because it costs less than doing a full investigation.

As Sydney and Golfman have said:

You do not need to log nonconforming material - you only need to identify in some fashion, disposition and move on. In fact many people actually take low $ value parts and simply throw them in a ‘red bin’ that gets trashed.

There is NO requirement to investigate to root cause all nonconforming material - it is up to you as you deem appropriate.

Remember nonconforming material is not the same as an audit nonconforming finding…

thank you all, this gives me some great ideas. this site seems very helpful.

Golfman25 said:

if it's a few pcs. and less than a few dollars.

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If you don’t track it, how do you know it is just a few pieces? Parts don’t get inspected before moving to inventory, what, in itself is a bad practice. They pick 20 today and find 2 scratched. Tomorrow they pick 15 and find another 2 defective. They could be having 150,000 DPPM with the “impression” it is only a few bad parts.

This is actually fairly simple. I’ve done it for decades.
First decide way items you will do this for. Usually low cost and - for me at least - commodity parts and only rarely custom parts (high volume low cost).

The scrap quantity shows as a material variance. In practical terms it shuts - or seriously slows the production line down so they don’t want to just accept too much low value scrap. We always had a ‘lean’ line where only the correct number of parts were delivered to the line for that day’s build schedule. The impact on builds was immediately felt. Some parts were delivered in bulk but really not enough to last a few days so again too much scrap was felt pretty quickly. Even without a lean line the buyer should be watching their usage variances to keep control of purchases.

As for inspecting parts prior to moving to inventory that is not done on a dock to stock program unless sufficient defects are found (see above) and commodity parts are rarely inspected in any case.

You may want to track basic categories and totals for "low value" scrap so you can see on a monthly or quarterly basis if the total scrap for similar causes is great enough to need action. One you identify a category that needs attention, you can then focus on one area or type of scrap to further narrow down what actions are needed.

And as Bev D says just above, if a small amount of scrap causes significant production problems, it needs attention sooner rather than later.