Should contact Rehm Thermal they have a whitepaper on pros and cons of Vapor Phase vs Convection....
Vapor phase traditionally targeted heavy PCB, large mass products better then lighter ones, due to ramp rate control being harder to attain vs say a standard convection oven. But peaks control, and delta T in liquidous in Vapor phase is better than in Convection.
Also repeatability of profile in the ramp to spike in Vapor Phase is not as good as a good Convection Reflow as most machines rely on using a non-homgenous less dense thermal transfer gas sitting above the main vapor cushion - has turbulance etc thus repeatability - board after board can be not as good as Convection Reflow) as most customers tend not to profile their Vapor phase systems much due to it being more painful this is not seen as much. This is generallisation and depends heavily on product type produced and machine build and type...(based mainly on the open pot types with condensation gas capture at top)
Also if production runs small the effects above will not be as evident.
You can gain inert attomsphere in Convection reflow with N2, but have to trade off n2 costs vs production qty Galden is pricy too and depending on machine model and construction some machines eat galden when used long for production runs due to design of machine. Also Galden pretty much has a sole supplier globally....
Yes Vapor phase is BATCH, no such thing as a inline system as such, some makers market it as such but is really PCB handling system bolted onto a batch process.
(Rehms Condenso(Vapor) machines work differently than ALL the others to counteract this alot of these issues, ramp rate control, reduced galden usage etc...)
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