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Vapor Phase vs Convection for production

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#63651

Vapor Phase vs Convection for production | 28 January, 2011

Hi All, We're looking to replace one of our reflow ovens. I'm hoping that someone out there can give me a list of pros and cons of vapor phase vs convection for production reflow. Thanks, Shannon

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#63652

Vapor Phase vs Convection for production | 28 January, 2011

Shannon, We have been using VP for all of our lead free production since 2007. Here are the items I can think of off the top of my head.

Pro's - small footprint, minimal profiling needed once machine is understood, oxygen free soldering process, stable peak temp, low energy usage

Con's - batch process, expensive fluid, some parts cannot be processed due to fluid drag-out, longer cycle time due to batch, need stand-off tooling for double sided boards.

Email me if you want more specifics

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#63662

Vapor Phase vs Convection for production | 28 January, 2011

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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#63689

Vapor Phase vs Convection for production | 4 February, 2011

There are also inline VP soldering machines too, go to this web site:

http://www.ibl-tech.com/products_slc-blc.html

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#63758

Vapor Phase vs Convection for production | 15 February, 2011

R&D Technical Services out of Burnsville, Mn. sells inline machines. http://www.rdtechnicalservices.com.

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#63759

Vapor Phase vs Convection for production | 15 February, 2011

Atek has available a complete line of German made laboratory, medium volume batch, and inline Vapor Phase systems.

http://www.atekllc.com/html/vapor_phase_.html

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#63791

Vapor Phase vs Convection for production | 18 February, 2011

#63800

Vapor Phase vs Convection for production | 21 February, 2011

They all are inlineish They just carry the board to the vapor chamber. in a reflow system all the boards in the oven from beginning to end are in state of process, which gives you more speed. If the board has a long cycle time VP is not a problem. If a short cycle time it is. You also pay up for the internal Conveyors. I have used both. I will admit that for the most part VP can do a nice job on boards. However they can be a pain in the ass too, Chemicals and maintenance etc. For most boards Reflow ovens you just turn them on a forget them.

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reflow oven profiler

HeatShield Gel- thermal PCB shield during reflow