The main difference between SMT SPI and AOI machine is that SPI is a quality check for paste presses after stencil printer printing, through the inspection data to solder paste printing process debugging, verification and control; SMT AOI is divided into two types: pre-furnace and post-furnace. The former tests the device mounting and the stability of the pasting in front of the furnace, while the latter tests the solder joints and the welding quality behind the furnace.
SPI(Solder paste Inspection) is the quality inspection of solder printing and the debugging, verification and control of printing process. Its basic functions:
Timely discovery of the lack of print quality. SPI can intuitively tell the user which solder paste printing is good and which is bad, and provide a reminder of the type of deficiency.
Through a series of solder joints testing, the trend of quality change is found. SPI detects the quality trend through a series of solder paste tests, and finds out the potential factors causing the trend before the quality exceeds the range, such as the regulation parameters of printing press, human factors, solder paste change factors, etc. Then timely adjustment, control the trend to continue to spread.
AOI(Automatic optic Inspection) is in the SMT production process there will be a variety of mounting and welding bad, such as missing pieces, tombstone, offset, reverse, air welding, short circuit, wrong pieces and other bad, now the electronic components are getting smaller and smaller, by manual eye inspection, slow speed, low efficiency, AOI check the mounting and welding poor, the use of image contrast, under different light irradiation, bad will present different pictures, through the good picture and bad picture contrast, can find out the bad point, so as to carry out maintenance, fast speed, high efficiency.
Post time: Aug-10-2021