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Acceptance Standards for PCBA Processed Products
2021-09-28
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Author:Frank

Acceptance Standards for PCBA Processed Products
What are the quality standards for PCBA processing? What aspects should be tested when accepting PCBA processed products?

   1. Check the environment:

   1. Test environment: temperature: 25±3°C, humidity: 40-70%RH

   2. Within 1 meter of a 40W fluorescent lamp (or equivalent light source), the inspection product is 30 cm away from the inspector.

 

  2. Sampling level:

  Quality Assurance Sampling Standard: Implementation of GB/T2828.1-2003 secondary inspection and a sampling plan

  AQL value: CR:0 MAJ: 0.25 MIN: 0.65

 

pcb board

 3. Testing equipment:

  BOM list, magnifying glass, probe, patch location map

 

 Four, acceptance criteria:

1. Reverse:

The polarity point (white silk screen) on the component is consistent with the screen printing direction of the PCB board (acceptable)

The polarity point on the component (white screen) is not consistent with the diode screen on the PCB board. (be rejected)

2. Too much tin:

   The maximum height of the solder joint (E) can be extended to the top of the PAD or end cap metallization, to the solderable end, but not to touch the component body (acceptable)

   The solder has touched the top of the component body. (be rejected)

3. Reverse:

   If the exposed electrical material is exposed, the chip component will have the opposite direction to the material surface and the printed surface. Chip components only allow one ≤0402 component to be reversed per Pcs board. (Acceptable)

"If there is exposed electrical material, the chip part will have the same material surface as the printed surface. The chip component has two or more components, each Pcs board ≤ 0402. (be rejected) 

4. Air welding:

       The solder joints between the component leads and the PAD are wet and full, and the component leads are not lifted (acceptable)

  The component leads are not coplanar, which prevents acceptable soldering. (be rejected)

5. Cold welding:

   During the reflow process, the solder paste is fully extended, the tin on the solder joints is completely wetted, and the surface is smooth. (Acceptable)

  The solder paste on the solder ball is not completely reflowed, the appearance of the tin is black and irregular, and the solder paste has tin powder that is not completely melted. (be rejected)

6. Reduce the number of pieces:

  BOM list needs to install the patch bit but not installed (rejected)

   The BOM list requires that the patch bit number does not need to install the component, but the component is installed, and the redundant component appears in any position. (be rejected)

7. Loss:

   Any edge peeling is less than 25% of the component width (W) or component thickness (T), and the top metal plating lacks up to 50% (each end) (acceptable)

   Any cracks or dents exposed due to clicks, cracks or any damage on the main body of the glass parts, any gaps in the resistance material, any cracks or indentations. (be rejected) 

8. Foaming, layering:

  The area of foaming and delamination does not exceed 25% of the spacing between plated through holes or internal lines. (Acceptable)

"The area of foaming and delamination exceeds 25% of the pitch between plated through holes or inner conductors, and the area of foaming and delamination reduces the spacing of the conductive patterns to a minimum electrical gap. (be rejected)

 

  Only by strictly implementing the acceptance procedures can the quality of PCBA processed products be guaranteed. Only by paying more attention to quality can we survive in an increasingly competitive market.