In the SMT process the 2 main pieces of equipment which have over 90% affect on the quality of a product are 1) Solder Paste Printing & 2) Reflow oven. His focus has been the design and application of measurement tools used to improve manufacturing thermal processes and well as moisture sensitive component storage solutions. He has seen and worked with the electronic manufacturing industry from many points of view, including: technician, engineer, manufacture, and customer. (ECD) in Milwaukie, Oregon for over 39 years as a Senior Project Engineer. Paul been with Electronic Controls Design Inc.
It is much easier to create a profile with 8 settings vs 5.
#REFLOW MACHINE FREE#
Yes, you can set a profile for lead free in a 5-zone oven but you will have a much higher risk in maintaining a small delta "T" across the board. The profile for lead free can be easily be accomplished in an 8-zone reflow oven where is a 5-zone oven it will be difficult.
The future in our industry is lead free alloys. In my opinion it would be best to spend the money on the 8-zone reflow oven in respect to the 5-zone. Fritz has published over a dozen papers at various industry conferences. Design of Experiments (DoE) techniques have been an area of independent study. Fritz's educational background is in mechanical engineering with an emphasis on materials science. For your low-volume, low-mix application, you certainly don't need a high-end oven, but you will want more than an entry level machine if you want good process capability and reliability.įritz's career in electronics manufacturing has included diverse engineering roles including PWB fabrication, thick film print & fire, SMT and wave/selective solder process engineering, and electronics materials development and marketing. Not to say that thermal capability is the only factor to be considered, but it is the primary concern. Additionally, be sure that any oven purchased has a capable cooling section if we can't cool adequately it will be very difficult to control liquidus time.īest practice is to use your most difficult assembly to run profiles on candidate equipment, and select based on the ability to meet your desired profile with low measured delta-T. If the oven is configured with five equal-length zones, it may be difficult to achieve good control of liquidus time. York has installed over 600 Lead Free Lines in Europe with Solder and flux systems as well as Technical Support on SMT lines and trouble shooting.įrom a practical perspective, five (heating) zones is certainly enough, given that the length of the zones is configured properly. Greg York has over thirty two years of service in Electronics industry. I recently witnessed a BOX Oven type reflow system with a profile of 27 minutes 40 seconds which gave understandably terrible results but once profiled and set correctly that produced the goods. If the oven is ineffective then it won't matter how many zones you have. Obviously some ovens are better and more efficient than others so that would be my only constraint, make sure the oven is up to it in the first place. Passives are 0603 imperial or larger.įor this board, would we see an actual difference in manufacturing process reliability between 5-zone and 8-zone ovens?Īs long as you profile correctly it shouldn't really matter as we have many users, varied in size and complexities using 5 zone ovens. Smallest components are 0.5mm pitch BGA, 0.5mm QFN and 0.65mm TQFP. Our boards are 5" x 7", components on both sides, component with largestthermal mass is inductor 10x10圆mm.
We prefer to purchase a 5-zone oven as cost is lower, but are concerned that 5 zones may not be enough to ensure a reliable reflow process comparing to an 8 zone oven. We are a small electronics design company setting up an assembly line for small volume production.
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