Hi James,

 

Keep in ESD safe environment is fine for short period (say 1 to 2 days). I have no data for the PCB keep longer than 1 month. It will cause oxidation of PCBA test pads. ICT become a challenge. Hand soldering for components on the long storage is not good. As I mentioned before, delamination may happen.

 

 

Dear Wilson,

 

The point is all the PCBA WIP no need to conduct neither second reflow nor wave soldering process( but perhaps partial of the boards need hand soldering one or two components ),

and just waiting some assembly materials to finish it.

 

 

Hi James,

 

Will WIP SMT PCBA run Wave Soldering afterwards? Will the PTH do Hand Soldering afterwards? If yes, the long storage on work floor is not appropriate. The PCB and components will absorb moisture and cause components crack or PCB delamination during second reflow or wave soldering or even hand soldering. Refer IPC J-STD-033A to control the WIP.

 

 

Dear Friends,

 

One of our customer question our PCBA WIP management procedure since he saw some of SMT / PTH subassemblies boards were keeping in production area longer than 3 days,

Some of the boards are longer than one weeks and even a few pcs longer than 1 month, so we had a big discussion about the shelf life of the assembly boards but end of our discussion

It seems he was not convinced, hereby I need your help to let know is there any IPC standards to describe this rule?  

 

Thanks & Regards

 

James Lee

 

 

Legal Disclaimer: The information contained in this message may be privileged and confidential. It is intended to be read only by the individual or entity to whom it is addressed or by their designee. If the reader of this message is not the intended recipient, you are on notice that any distribution of this message, in any form, is strictly prohibited. If you have received this message in error, please immediately notify the sender and delete or destroy any copy of this message