Features of SMT: 1. High assembly density, small volume and light weight of electronic products. The volume and weight of SMT components are only about 1 / 10 of those of traditional plug-in components. Generally, after SMT is used, the volume and weight of electronic products are reduced by 40% ~ 60% and 60% ~ 80% respectively. 2. High reliability and strong anti vibration ability. The defect rate of solder joint is low. 3. High frequency characteristic is good. Reduced electromagnetic and radio frequency interference. 4. It is easy to realize automation and improve production efficiency. The cost can be reduced by 30% ~ 50%. Save materials, energy, equipment, manpower, time, etc. 1. Electronic products pursue miniaturization. The previously used perforated plug-in components can no longer be reduced, and the functions of electronic products are more complete. The integrated circuit (IC) used has no perforated components, especially for large-scale and high integrated IC, so surface mount components have to be adopted. The mass production and production automation are required. The manufacturer should produce high-quality products with low cost and high output to meet the needs of customers Market competitiveness. 1. In the production process, the waste water discharged after product cleaning brings pollution to water quality, earth, animals and plants. 3. The cleaning agent residue on the machine board brings corrosion phenomenon, which seriously affects the product quality. 4. Reduce cleaning process operation and machine maintenance costs. 5. The cleaning of PCBA group can reduce the damage caused by the cleaning process. There are still some components that cannot be cleaned. 6. The residual flux has been controlled and can be used in accordance with the appearance requirements of the product, so as to avoid the problem of visual inspection of the cleaning state. 8. The no washing process has passed many international safety tests, which proves that the chemical substances in the flux are stable and non corrosive. Design and manufacturing technology of electronic components and integrated circuits related to SMT. Component feeder and PCB are fixed, and the chip head (with multiple vacuum suction nozzles) moves back and forth between the feeder and the substrate to take the components out of the feeder, adjust the position and direction of the components, and then stick them on the substrate. Because the mounting head is installed on the X / Y coordinate moving beam of the arch type, it is named. The method of adjusting the position and orientation of components is as follows: 1) the adjusting position of mechanical alignment and the adjusting direction of nozzle rotation can be achieved with limited precision. 2) Laser identification, X / Y coordinate system position adjustment, nozzle rotation adjustment direction, this method can realize identification in flight, but it can not be used for BGA. 3) Camera recognition, X / Y coordinate system adjustment position, nozzle rotation adjustment direction, generally the camera is fixed, the film head flies across the camera, and carries out imaging recognition, which takes a little time than laser recognition. However, it can identify any component, and there is a camera identification system to realize identification in flight. There are other sacrifice in mechanical structure. This form is limited in speed due to the long distance the patch head moves back and forth. OEM OEM is now generally using multiple vacuum suction nozzles (up to ten) and using double beam system to improve the speed, that is, when the patch head on one beam is taking material, the patch head on the other beam is placing components, which is almost twice as fast as the single beam system. However, in practical application, it is difficult to achieve the conditions of simultaneous reclaiming, and different types of components need to be replaced with different vacuum suction nozzles, so there is a time delay in changing the suction nozzles.