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RE: Failure of Moisture Barrier Bags Shipped by Air

#4693

RE: Failure of Moisture Barrier Bags Shipped by Air | 8 March, 2000

This is just an Alert:

We had a lesson on the effect of air shipments of devices which have been fully saturated with moisture. After being in a pressure cooker for two hours in Singapore, devices were sealed in metalized vapor barrier bags. They were shipped by air to the U.S. for testing in an Altos 500-9 TVP drying system.

They arrived with 85% of the original moisture missing. The bags had been in a cargo bay for 20 hours. The equivalent altidude in the cargo hold is typically from 8,000 to 10,000 feet. This resulted in a positive pressure of 3.5 PSI (prox) in the bags. They internal atmosphere (and the moisture) leaked from the devices through the bags.

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#4694

Re: RE: Failure of Moisture Barrier Bags Shipped by Air | 8 March, 2000

Charles: Interesting. Best laid plans, eh.

Why don't you throw those pups into a glass of water and save some air freight? Or have you decided that shipping 'em is cheaper than buying the Altos? ;-)

Ta

Dave F

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#4695

Re: RE: Failure of Moisture Barrier Bags Shipped by Air | 9 March, 2000

DaveF:

Since these SMT "spounges" get wet in Singapore and they got to get dry in Singapore, the airfreight idea won't work. I don't think the airlines would be too thrilled with a teathered ballon floating 10,000 feet in the air over the city. STATS wouldn't buy into it because it would take 20 hours to get dry in the ballon and only 4-6 hours to be moisture-free in the new Altos TVP dryer.

Stu Stu

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