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To reduce the dross formation in wave soldering process

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#61612

To reduce the dross formation in wave soldering process | 15 April, 2010

Hi, Can any one help me for how to reduce the dross formation in wave soldeing process , currently we are getting very heavy dross formation in process

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#61615

To reduce the dross formation in wave soldering process | 15 April, 2010

Dross formation rates for SnCu and SAC are roughly 2.5 times the rate for SnPb (Hwang et al., 2004)

Methods for reducing dross are: * Lower pot temperature * Run pump speed slower and only when soldering * Check solder contaminants to BS219, ASTM B32-66T * Use nitrogen tenting * Buy only low dross cast bar

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#61646

To reduce the dross formation in wave soldering process | 19 April, 2010

We installed a fixed distance optical sensor above the conveyor rail and "wired it" throught he machines terminal bus to cut the pump on only when a board was present at the pot. We also installed a timer in line so the pump would only stay on long enough to completely wave our longest pallet/board. We reduced dross formation by a lot! We were cleaning the pot about every two hours prior to switch installation. We currently can go about two days of steady running before we "have to" clean it.

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#61648

To reduce the dross formation in wave soldering process | 19 April, 2010

Ralph Woodgate says that pump speed is the biggest driver to dross production

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#61665

To reduce the dross formation in wave soldering process | 22 April, 2010

Davef, who is Ralph Woodgate?

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#61666

To reduce the dross formation in wave soldering process | 22 April, 2010

Ralph Woodgate is the 'god of wave soldering process control.' We believe he is now retired, but in olden times his presentations at SMTA meetings were 'DO NOT MISS.' We imagine you can find his books on the used book market. Look here: http://users.rcn.com/woudyet/author.htm

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#61668

To reduce the dross formation in wave soldering process | 22 April, 2010

Thanks! I've been re-inventing the wheel again!

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#61683

To reduce the dross formation in wave soldering process | 24 April, 2010

HI, Can pl. provide the some detail on recomanded pump speed

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#61693

To reduce the dross formation in wave soldering process | 26 April, 2010

What type of wave machine? Does your machine have a pump speed dial? Does your machine have the ability to raise and lower the pot? Raise pot to as close as possible to the pallets/boards and make sure they can pass over the nozzle without hanging on anything like the top of the nozzle. Then run a test board/pallet through and adjust the pump speed (if you have a dial to do this) till the wave (while the board/pallet is passing over it) is surging about half way past the mid point of the thickness of the pallet(or so). Some fine tuning of the speed may be necessary to get optimum results.

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#61694

To reduce the dross formation in wave soldering process | 26 April, 2010

Set pump speed so that the board is 1/3 to 1/2 immersed as it goes through the wave.

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