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Process Parameters Wave soldering
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Process Parameters Wave soldering

In this article you will find some basics to start / check the Parameters for a wave soldering machine. You will also find and a explanation of the technical vocabulary such as "Dwell time, Solidification time and wetting time.

 
Preheating
The temperature of the board (component side) during preheating should go as quick as possible to 45 °C (with maximum slope of 2 °C/Sec) and just before soldering an temperature of 85 °C.
 
Wetting time

The time between the moment of first contact (between the parts to be soldered) and the solder, and the moment that the solder in the joints starts solidifying.

 
Dwell time

The time between the moment of first contact (between the parts to be soldered) and the solder, and the moment of last contact with the solder.
(This time should be between 2 and 4 seconds.)

 
Soldering time

The time between the board actually contacts the solder and the onset of solidification.
(Dwell time + approximately. 5-10 Sec.)

 
Solidification time:

The time solder is getting solid on the bottom of the board.

 
Cooling time:

Forced cooling after soldering reduces the maximum temperature reached in the areas on the component side of the board.
However, forced cooling directly after solder bath, may cause unequal contractions, which will initiate cracks and therefore not advised.
If cooling down is needed because of the temperature from the carrier is rising to high, the best place will be before or in the lift itself.

 
References


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