What kind of PCB can be welded by PCBA?

When welding PCBA, there are usually many requirements for PCBA boards, and only boards that meet the requirements can be welded. So why do welding processes require so many requirements for boards? Originally, the processing of PCBA will go through a lot of special processes, and the application of special processes immediately brings the requirements for PCB boards. If there are problems with PCB boards, it will increase the difficulty of PCBA welding process, which may eventually lead to welding defects and unqualified boards. Therefore, in order to ensure the smooth completion of special processes and facilitate PCBA welding, PCB board should meet the manufacturability requirements in terms of size, pad distance, etc. Let’s take a look at the requirements of PCBA welding for PCB board today.
1. PCB size
The width of PCB (including board edge) should be greater than equal 50mm and less than 460mm, and the length of PCB (including board edge) should be greater than equal 50mm. If the size is too small, it needs to be made into a puzzle.
2. Width of PCB board edge
Side width: > 5mm, splice spacing: < 8mm, and distance between pad and board edge: > 5mm.
3. Bending of PCB
Upward bending degree: < 1.2mm, downward bending degree: < 0.5mm, PCB twist degree: maximum deformation height ÷ diagonal length < 0.25. 4. Mark point of PCB board Mark's shape: standard circle, square and triangle; Size of Mark: 0.8 ~ 1.5 mm; Mark's material: gold plating, tin plating, copper platinum; Mark's surface requirements: the surface is flat, smooth, free of oxidation and dirt; Mark's surrounding requirements: there should be no green oil or other obstacles within 1mm around, which is obviously different from Mark's color; Mark's location: more than 3mm away from the board edge, and there can be no through holes and test points similar to Mark within 5mm around it. 5. PCB pads There are no through holes on the pads of SMD components. If there is a through hole, the solder paste will flow into the hole, resulting in less tin in the device, or the tin will flow to the other side, resulting in uneven board surface, and the solder paste cannot be printed. When designing and producing PCB, it is necessary to know some knowledge of PCB welding process, so as to make the products suitable for production. Knowing the requirements of the processing plant first can make the later manufacturing process smoother and avoid unnecessary troubles. This is the requirement of PCB for PCBA welding process. When producing PCB, we should not slack off. Only by producing high-quality and compliant PCB can we make the PCB accept other special processes better, and give the PCB life and inject the soul of function.