SMT Process: SPI (Solder Paste Inspection)

SMT Basic Process:

SMT Line Logic:

Production is very important but quality comes first that's exactly why after each stage that add value in SMT we must apply inspection stage it's simply a desired waste to insure SMT line quality

What is AOI ?

The term AOI stands for Automatic optical inspection in which an inspection machine take pictures or measure height , volume and area (using laser beam) of SMT material and compare it to reference (image frame or value) and decide if it's defect or good product

SPI (Solder Paste Inspection):

An inspection machine that generate a 3D image of solder paste print using laser beam 

to perform a 3D inspection by calculating and visualizing of Volume, height and area of solder paste on the PCB and view it in analytic way (Graphs, histograms and Pareto charts)

Defects:

Video:

SMT Process: Screen Printer

SMT Process: Screen Printer

It's a Machine that print solder paste on Copper pads of PCB (printed circuit board) 

using metal mask and squeegee 

Metal Mask

Solder Paste

Metal Mask and Squeegee

Screen Printer Process

Management Points:

• PCB Size (L,W,T) , PCB fiducial marks (X,Y) .
• Screen Printer Parameters like: Squeegee Speed (print speed), Print pressure (Squeegee force), Separation speed, Metal mask Cleaning Cycle.
• Solder paste should be ready (mixed for 2 min on 1000 RPM in mixer) and on room temperature.

Defects & Errors:

• Short Circuit ( Bridge)
• Excessive Solder Volume 
• Insufficient solder volume or area
• shifted print

Video Contents :

1. Homing machine
2. Load job file
3. Adjust conveyor
4. Insert magnetic block support 
5. Insert Metal mask
6. Add solder paste
7. Run production