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Moisture Attraction Inside Moisture Barrier Bag

Moisture Attraction Inside Moisture Barrier Bag

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Has anyone experienced more moisture adsorbing into the mois... - Jul 08, 2021 by Steel Camel

Just to be clear, you mean the card says that the moisture l... - Jul 08, 2021 by Stephen

Not a Vacuum Person and yes, the moisture level reads good, ... - Jul 08, 2021 by Steel Camel

> ...but the part has too much moisture. <BR> &... - Jul 09, 2021 by dontfeedphils

I was once part of a conference call with a component manufa... - Jul 09, 2021 by Stephen

Great Question 1. Informal Testing with scales from Enginee... - Jul 09, 2021 by Steel Camel

A test that I would like to see is, expose parts for 24 hour... - Jul 12, 2021 by Stephen

Thank you for suggested test. Very solid. I will run it by ... - Jul 13, 2021 by Steel Camel

Steel Camel

#86838

Moisture Attraction Inside Moisture Barrier Bag | 8 July, 2021

Has anyone experienced more moisture adsorbing into the moisture sensitive part than the beads in the approved desiccant bag in the MBB. The reason for this is a concern is by having the part adsorb more moisture, the HIC card can give a false reading.

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Stephen

#86839

Moisture Attraction Inside Moisture Barrier Bag | 8 July, 2021

Just to be clear, you mean the card says that the moisture level is good but in reality the part has too much moisture?

And you are not one of those people that vacuum seal MBBs with as much vacuum as possible are you? If you do more than lightly evacuate air then you can isolate the HIC from the desiccant. And isolate the parts from the desiccant. And a strong enough vacuum will draw moisture through the MBB and possibly cause corners to poke through the MBB ripping holes in it.

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Steel Camel

#86840

Moisture Attraction Inside Moisture Barrier Bag | 8 July, 2021

Not a Vacuum Person and yes, the moisture level reads good, but the part has too much moisture.

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dontfeedphils

#86843

Moisture Attraction Inside Moisture Barrier Bag | 9 July, 2021

> ...but the part has too much moisture.

How do you know?

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Stephen

#86844

Moisture Attraction Inside Moisture Barrier Bag | 9 July, 2021

I was once part of a conference call with a component manufacturer. The call was starting to get heated as the manufacturer was certain that we were not storing the parts properly and we knew that we were. Then one of their people asked how many we had bought. We said 500. Then he said they never shipped anything other than quantities of 1,000.

I was not part of the call to the distributor that had split the reel. I think that would have been the fun one.

If the parts were exposed and then a fresh card put in before shipping then the card might not show that. I think you might need to have the same card with the part the entire life of the part. But that won't happen.

Check if the parts might have been exposed somewhere along the supply chain. The manufacturer probably knows how to handle them. You know how to handle them but a distributor that splits quantities, maybe not.

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Steel Camel

#86845

Moisture Attraction Inside Moisture Barrier Bag | 9 July, 2021

Great Question

1. Informal Testing with scales from Engineering Students at San Jose State. Report available upon request.

2. Internal Testing - Informal with scale

3. Visiting, Listening and Learning from SMTA Engineers...unfortunately, they wish to remain anonomyous.

4. Self experimenting with military, JEDEC, IPC approved dessicant beads in glass jars kept in windowsill for 5 days.

5. Visit to local manufacturer and meeting with engineer and QC manager where load to europe was rejected.

Hope this helps. djenkins@steelcamel.com

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Stephen

#86850

Moisture Attraction Inside Moisture Barrier Bag | 12 July, 2021

A test that I would like to see is, expose parts for 24 hours 40%-60% RH, 25C for 24 hours. Then seal with a HIC and minimum desiccant that Jstd 33 requires. Five to seven days later open and see if HIC says good but parts have excess moisture.

I think similar scenarios happen a lot with distributors that split packages.

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Steel Camel

#86853

Moisture Attraction Inside Moisture Barrier Bag | 13 July, 2021

Thank you for suggested test. Very solid. I will run it by the engineering dept at San Jose State.

thank you.

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