After the PCB board is drilled, various holes on the PCB board will appear different degrees of sharp edges due to different drilling parameters, life of the drill tip and other factors. When the burring occurs, it needs to be polished with sandpaper. When grinding, dust will fall on the board or in the hole. If the subsequent treatment is poor, it will cause product quality problems or scrap. Therefore, PCB boards after drilling need to go through the burring process before entering the next process.