Well, I know your problem from live experience in your area. Been there, saw the results and was not amused.
I share your concern.
Tell us what you are producing so we don´t buy such goods ;-)
 
If you have no other choice than that you may consider establishing a FIFO system for all of your parts. Make sure all parts do not stay longer than absolutely necessary in this environment.  Make sure, once you have determined the max. storage time for an individual part, that parts staying there longer don´t get to your assembly. Think of "just in time delivery", maybe you´re a big one and can do it. Get accustomed to the idea that not all parts can be used for production.
If all that doesn´t help get as much touchup people you can get,  .... but if that will make things any better.... ?
 
BEST: You may seal the parts in dry bags as you do with all your MSD. Do solderability tests before use, don´t process parts that show evidence of bad wetting. I would call that "Control of the conditions for the indivdual part" and that would be my first choice than.
I guess your next problem will be the conditions in your assembly.
 
Good luck and please do better than others over there
 
Wolfgang
 
-----Original Message-----
From: sangliu [mailto:[log in to unmask]]
Sent: Thursday, March 14, 2002 3:09 AM
To: [log in to unmask]
Subject: [TN] Ask the question about Storage conditions

Hello to all:
    I have meet with a seriously problem: Our factory set up a new storage center. But somebody do not want afford the air-conditioning for the component and PCB materials storaging. I and someother engineers do not think so, and afraid the solderability ,reliability and the other problems.
Because the temperature maybe 40 degree C odd ,and the humidity will be 90%RH.
 
Would you please give me some materials about such topics:
1:The storage conditons of your company and the company you know, such as temperature,humidity, and so on. Also you can send me the standard document in electronic field.
 
2: The storage limit time of different materials, packages types, and the oxidate rate of the common metal: SnPb, Au, Ag, Pd,etc.
 
3: The main harmful when we can not afford good storaging condition, especailly the details data /photo and report on this problem.
 
4: I know sometimes the packing materials such as plastic film, polyester, polyethelene  can not hold back the moisture, because they have micropore.
Do you have some papers on these packing materials for this model?
 
  Regards!
 
Sunny Liu
 
************************************************************
  Dr. Liu Sang                           
  Process Technology Section of Development & Piloting Department
  Huawei Technologies Compant, LTD.
  Bantian, Longgang,
  Shenzhen 518129 P.R.China
  Tel:  (86)-755-8780073, Fax: (86)-755-8780132
  E-mail: [log in to unmask]
  http://www.huawei.com
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