PCBA Tech - SMT processing production line configuration requirements

SMT chip processing is a highly demanding precision electronic processing process. Electronic products have more complete functions. The integrated circuits (ICs) used have no perforated components, especially large-scale, highly integrated ICs, so surface mount chips have to be used. element. Strictly speaking, a complete PCBA circuit board is not a simple board, it is a collection of high-tech. From up to hundreds of thousands of light-years out of the aircraft, as small as the remote control used at home, the chip is as small as 5mm, and then integrated into the circuit board through SMT chip processing and DIP plug-in post-welding, so as to achieve a variety of Kind of function.

SMT patch processing production lines can be divided into automatic production lines and semi-automatic production lines according to the degree of automation, and can be divided into large, medium and small production lines according to the scale of the production line.

Fully automatic production line means that the entire production line equipment is fully automatic. All production equipment is connected into an automatic line through automatic loading machine, buffer connecting line and unloading machine. Semi-automatic production line means that the main production equipment is not connected or not fully connected. Connected, the printing machine is semi-automatic, requiring manual printing or manual loading and unloading of printed boards.

The following is an explanation of the workstations involved in a typical production line.

1. Printing: Its function is to print solder paste or patch glue onto the pads of the PCB to prepare for the soldering of components. The equipment used is a printing machine (stencil printing machine), located at the forefront of the SMT production line.

2. Dispensing: It is to drop the glue onto the fixed position of the PCB, and its main function is to fix the components on the PCB. The equipment used is a glue dispenser, located at the forefront of the SMT production line or behind the testing equipment.

3. Mounting: Its function is to accurately mount the surface mount components to the fixed position of the PCB. The equipment used is a placement machine, located behind the printing machine in the SMT production line.

4. Curing: Its function is to melt the patch glue, so that the surface mount components and the PCB are firmly bonded together. The equipment used is a curing oven, located behind the placement machine in the SMT production line.

5. Reflow soldering: Its function is to melt the solder paste, so that the surface mount components and the PCB are firmly bonded together. The equipment used is a reflow furnace, located behind the placement machine in the SMT production line.

6. Cleaning: Its function is to remove the harmful welding residues (such as flux, etc.) on the assembled PCB. The equipment used is a washing machine, and the location may not be fixed, it may be online or offline.

7. Inspection: Its function is to inspect the welding quality and assembly quality of the assembled PCB. The equipment used includes magnifying glass, microscope, in-circuit tester (In-circuit Tester, ICT), flying probe tester, automatic optical inspection (Automated Optical Inspection, AOI), X-ray inspection system, functional tester, etc. The location can be configured in a suitable place on the production line according to the needs of the inspection.

8. Rework: Its function is to rework the PCB that has been detected to be faulty. The tool used is a soldering iron, which is usually carried out in a rework station.