Detailed knowledge of double sided circuit board welding. Compared with the single panel, the double-sided circuit board has higher wiring density and smaller aperture. The metallized holes on which interlayer interconnection depends are directly related to the reliability of printed circuit boards. With the narrowing of the aperture, some sundries, such as grinding debris, volcanic ash, etc., once left in the hole, will make the chemical precipitation of copper, electroplating copper lose its effect.
In order to ensure the reliable conductive effect of the double-sided circuit, the connection hole on the board should be welded with wire first, and cut out the protruding part of the connection wire tip, so as to avoid stabbing the operator’s hand. This is the connection line preparation of the board. So, what should we pay attention to in the welding of the double-sided circuit board?

1. The device that requires shaping shall be shaped first and then inserted according to the requirements of the process drawing.

2. The type face of the diode after shaping should be facing up, and the length of the two pins should not be inconsistent.

3. When installing devices with polarity requirements, it should be noted that the polarity should not be reversed. No matter whether the device is vertical or horizontal, there should be no obvious tilt.

4. The power of the electric iron used for welding is between 25 and 40W, and the temperature of the electric iron head should be controlled at about 242℃, and the welding time should be controlled at 3 to 4 seconds.

5, welding generally in accordance with the device from low to high, from the inside to the outside of the principle of welding to operate, welding time to master, too long time will burn the device, will also burn the copper clad wire on the copper clad plate.

6. Since it is double-sided welding, a process frame for placing the circuit board should also be made, with the purpose of not pressing and slanting the device below.

7. After the completion of the welding, a comprehensive inspection shall be carried out to check the places where there is missing insertion and welding. After the confirmation, the pins of the redundant devices shall be trimmed and flow into the next procedure.

8. The specific operation shall also strictly follow the relevant process standards to ensure the welding quality.