The temperature curve of how to debug BGA rework station

The temperature curve of how to debug BGA rework station

1, preheating and heating section for a part, this part of the role is to reduce the temperature of PCB,

remove moisture to prevent foaming, prevent the heat damage, the general temperature requirements

are: when the second section of the temperature of the test temperature of the tin in (lead: 145~160 C,

there is a high, it means that we set the temperature of the heating temperature is high, can reduce the

temperature of the heating section. If so, can the preheating section and a heating section of the high

temperature or longer time. If it is stored for a longer time is not baked PCB plate can be the first time

to warm up some of the time to bake the board to remove moisture.

2, a constant temperature segment for a part, general our constant temperature temperature setting to

Bishengwen to some lower, this is let the temperature inside the tin ball maintain a slow heating to

achieve constant temperature effect. This part is activated flux and removal to be welded metal surface

oxides and table mask and flux of volatiles, enhance the wetting effect, reducing the temperature of the

role. The general constant temperature section of the actual test tin temperature control requirements

in lead-free: 170~185 DEG C, lead 145~160 DEG C) if high, can reduce the temperature by some, if low

can the temperature heightening some. If the temperature is too long or too short, can be adjusted by

lengthening or shortening the time of constant temperature.

3, fusion welding and welding for a part, this part is to solder and PCB pad good fusion, that in this section

we mainly to achieve is welding peak (lead-free: 235~245 DEG C lead: 210-220 DEG C) if the measured

temperature is high, can reduce the melting welding temperature or shorten the thawing time welding

section. If the measured temperature is low, the temperature of the high melting temperature or the time

of the extension and the fusion welding can be added. Common BGA chip melt welding time we are

limited to 100 seconds, that is, when the temperature is low, we add time, more than 100 seconds when

the temperature is low, we choose to add high melting temperature, if the 75 seconds to reach the ideal

peak then we can change for fourth seconds to 75 seconds.