Electronics Forum | Wed Jul 30 00:05:05 EDT 2003 | praveen
Hi, I am observing warpage in the PBGA during reflow in rework machine.Reflow profile is std. (Peak temp is 214 deg C using 63/37 paste). Please advise what should be the gap between the nozzle and the BGA body during reflow process in SRT BGA rework
Electronics Forum | Thu Jul 31 09:03:36 EDT 2003 | russ
Are you baking the parts prior to installation? I have found that this will help in some cases. Russ
Electronics Forum | Thu Jul 31 12:08:12 EDT 2003 | Kris
Hi, Are you printing the paste uniformly ?
Electronics Forum | Thu Jul 31 21:22:57 EDT 2003 | praveen
Yes the paste printing is uniform. I have not tried out paste flux yet.
Electronics Forum | Thu Jul 31 15:29:25 EDT 2003 | bcceng
A couple of things you can look into 1. The proper bottom pre-heat of board. If you are applying only direct hot air to BGA without preheating can cause BGA's to warp and collapse un-even. 2. Moisture on you BGA's. If BGA's were not properly packa
Electronics Forum | Thu Jul 31 21:21:54 EDT 2003 | praveen
Yes we are baking the boards and the BGA. Using a CDM material pallet to hold the PCB as clamping is a problem without that.
Electronics Forum | Wed Jul 30 23:16:01 EDT 2003 | praveen
The profile is enclosed.The PBGA is 37x37 mm.I am keeping the gap about 4-5 mm.The profile meets the solder paste spec.Peak temp is 211 deg C,Above melting point 77 sec. rate of heating
Electronics Forum | Wed Jul 30 22:37:15 EDT 2003 | Dean
I have been using a srt-1000 since 98. My guess is your heating up the part too fast. What is your heating rate (deg. C per second)? PBGA's do warp. Your profile should mimic your smt process (assuming you have no warping there). Also, check wit
Electronics Forum | Fri Oct 17 22:37:01 EDT 2003 | Albert Gu
Who has the opertion manual for SRT Sierra Summit 1000/1100 BGA Rework system?? Urgent help need. Can you email me or fax to 0086-571-86730015. Many thanks for your kindly help
Electronics Forum | Mon Aug 04 17:35:08 EDT 2003 | Dean
If you lay a flat edge on the PBGA, it is visibly warped? How much of a warp? 0.001, 0.010, 0.050 what? What is your pcb temperature just prior to entering the spike process (zone or step or what ever you call it)? Is it between 165 and 175 C?
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