Why does PCB production need to be pieced board
General circuit board assembly is mainly to increase the production efficiency of SMT production line, PCB usually has the so-called "several in one" board, PCB assembly to increase the number of SMT parts, can increase the utilization rate of the SMT machine, improve the efficiency. PCB assembling board has another advantage, it can save time when taking and placing PCBA, because multiple boards can be taken and placed at the same time. If the subsequent board level test can be done with board testing, the wasted time of taking and placing boards in the fixture can be greatly saved.
Based on quality considerations, it is really not recommended to use hands to break off the excess edge of the plate, should be used to remove the edge of the machine equipment, in order to reduce the impact of the stress generated by the folding edge on the board and parts. PCB board edge design is mainly used to assist PCBA assembly and production. At present, the SMT production line is highly automated, and the delivery of boards depends on belts and chains. The main purpose of the board edge is to transport boards for these belts and chains.
The main reason for the reserved process edge in PCB production is that the track of SMT mounter is used to clamp the circuit board and flow through the mounter. Therefore, when components too close to the track edge are absorbed by the mouthpiece of SMT mounter and pasted onto the circuit board, collision occurs and the production cannot be completed. Therefore, in the process of PCB assembling, in order to consider the subsequent patches and plug-ins, Generally add process edge, let Shenzhen Runze Wuzhou Electronic Technology Co., Ltd. to introduce the advantages of PCB circuit board reserved process edge:
The reserved process edge is the part added on both sides or four sides of PCB board to assist the patch plug-in to weld the missing board, which is mainly to assist production and does not belong to the PCB board. It can be removed after the PCBA manufacturing and production is completed.
PCB production reserved process edge will consume more boards, increase the cost of PCB production, so in the design of PCB process edge, need to balance economy and manufacturability. For some special circuit boards, PCB boards with 2 or 4 process edges can be greatly simplified by means of PCB splicing. SMT processing in the design of the whole way, fully considering the track width, SMT placement machine for more than the width of 350 mm makeup need communication with SMT process engineer of supplier.
PCB production process edge flatness is also an important part of printed circuit board production. When removing PCB production process edges, it is necessary to ensure smooth process edges, especially for circuit boards with high assembly accuracy requirements. Any uneven rough edges will lead to offset installation holes and bring great trouble to subsequent PCBA assembly.