Sheet metal storage after use 1

[Nashanas]

Hello,

I have a very basic question. We work with a lot of sheet metal, most of it is austenietic stainless steel. Our operator at the cutting machine unrolls a nudle of sheet but after he has cut the amount of material required, he rolls the sheet back and used metalic strips to hold the roll together and puts it back in the warehouse.

One of the client QI saw this and pointed out that sheet metal rolls after usage should be latched using plastic strips instead of metalic strips to avoid material contamination.

I want to know of there is any international standard which speaks about storage and latching of sheet metal rolls?

Thank you for your time.

 

[EdStainless]

While using steel banding on SS is common there is usually a protective strip of cardboard or paper under to minimize the amount of iron being picked up on the surface.
But the real issues is don't you acid clean (passivate) after you have done any further cutting or forming?
There are standards for the cleaning of SS (ASTM A380 and ASTM A967), it is presumed that however the steel is processed or stored or handled will be 'fixed' if needed. This is the responsibility of each party in the supply chain.

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P.E. Metallurgy, consulting work welcomed

 

[Nashanas]

Yes, we do the passivation of the final products. I will look in to these standards now, thank you.

 

[EdStainless]

Check into how you have tested to verify that your passivation works.
Also check into your acid control (concentration, temperature, metals content).
These both would only need to be checked periodically (every few weeks for acid quality and maybe annually for effectiveness).

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P.E. Metallurgy, consulting work welcomed

 

[kingnero]

Weird that the QI would comment on the use of steel strips but nothing about the steel shears...

 

[EdStainless]

The shears themselves are hard enough that there is no transfer of metal.
But handling does the material touch any other steel parts? (racks, guides, supports)
This is the most common source of contamination of SS surfaces.
In a proper SS facility there is no steel contact, everything is capped with hardwood or HDPE.
Oh, and no Cu alloys either.

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P.E. Metallurgy, consulting work welcomed

 

[WKTaylor]

two other minor suggestions.

Deburr the cut/sharp edges... and round-off both sharp corners... of the sheet to prevent scratching/marring with incidental contact.

Ensure that any short pieces of sheet metal, that may be useful for small parts, are fully identified by mill-markings... hand written is OK as long as the procedure is established/followed. There is nothing worse than to need a small piece of material and the alloy, temper/condition, origin markings, etc are missing... especially where multiple mill-runs and various alloy/temper materials are being used/stored. These pieces are now essentially 'scrap'... DO NOT USE material that cannot be positively identified!

Regards, Wil Taylor
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